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Introduction: Diabetic retinopathy screening (DRS) attendance in young adults (YAs) is consistently below recommended levels. The aim of this study was to identify barriers and enablers of DRS attendance among YAs in the UK living with type 1 (T1D) and type 2 diabetes (T2D)., Research Design and Methods: YAs (18-34 years) were invited to complete an anonymous online survey in June 2021 assessing agreement with 30 belief statements informed by the Theoretical Domains Framework (TDF) of behavior change describing potential barriers/enablers to DRS., Results: In total, 102 responses were received. Most had T1D (65.7%) and were regular attenders for DRS (76.5%). The most salient TDF domains for DRS attendance were ' Goals ', with 93% agreeing that DRS was a high priority, and ' Knowledge ', with 98% being aware that screening can detect eye problems early.Overall, 67.4% indicated that they would like greater appointment flexibility (Environmental context/resources ) and 31.3% reported difficulties getting time off work/study to attend appointments (Environmental context/resources ). This was more commonly reported by occasional non-attenders versus regular attenders (59.1% vs 23.4%, p=0.002). Most YAs were worried about diabetic retinopathy (74.3%), anxious when receiving screening results (63%) ( Emotion ) and would like more support after getting their results (66%) ( Social influences ). Responses for T1D and T2D were broadly similar, although those with T2D were more likely have developed strategies to help them to remember their appointments (63.6% vs 37.9%, p=0.019) ( Behavioral regulation )., Conclusions: Attendance for DRS in YAs is influenced by complex interacting behavioral factors. Identifying modifiable determinants of behavior will provide a basis for designing tailored interventions to improve DRS in YAs and prevent avoidable vision loss., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Aim: To estimate the minimally important difference (MID) in change in National Eye Institute Visual Function Questionnaire-25 (VFQ-25) composite score using methods aligned with patient perception., Methods: Retrospective analysis of prospectively collected data from adults with primary angle closure or primary angle closure glaucoma enrolled in the Effectiveness, in Angle-closure Glaucoma, of Lens Extraction study. We included data from 335 participants with patient reported visual function (VFQ-25) and health status measured by the EQ-5D-3L over 36 months. We used the recommended anchor-based methods (receiver operating characteristic (ROC), predictive modelling and mean change) to determine the MID of the VFQ-25. EQ-5D-3L anchor change was defined as none (<0.065); minimal (0.065≤EQ-5D-3L change ≤0.075 points) and greater change (>0.075 points)., Results: Mean baseline VFQ-25 score was 87.6 (SD 11.8). Estimated MIDs in the change in VFQ-25 scores (95% CI) were 10.5 (1.9 to 19.2); 3.9 (-2.3 to 10.1); 5.8 (1.9 to 7.2) and 8.1 (1.7 to 14.8) for the 'within-patient', 'between-patient' change, ROC and predictive modelling anchor methods respectively. Excluding estimates from the methodologically weaker 'within-patient' method, the MID of a change in VFQ-25 composite score is 5.8 (median value)., Conclusions: Estimates of the MID using multiple methods assist in the interpretation of the VFQ scores. In the context of early glaucoma related visual disability, a change score of around six points on the VFQ-25 is likely to be important to patients. Further confirmatory research is required. Studies comparing changes in patient-reported outcome measure scores with a global measure of patients' perceived change are required., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Effective population screening for glaucoma would enable earlier diagnosis and prevention of irreversible vision loss. The UK National Screening Committee (NSC) recently published a review that examined the viability, effectiveness and appropriateness of a population-based screening programme for primary open-angle glaucoma (POAG). In our article, we summarise the results of the review and discuss some future directions that may enable effective population screening for glaucoma in the future. Two key questions were addressed by the UK NSC review; is there a valid, accurate screening test for POAG, and does evidence exist that screening reduces morbidity from POAG compared with standard care. Six new studies were identified since the previous 2015 review. The review concluded that screening for glaucoma in adults is not recommended because there is no clear evidence for a sufficiently accurate screening test or for better outcomes with screening compared to current care. The next UK NSC review is due to be conducted in 2023. One challenge for POAG screening is that the relatively low disease prevalence results in too many false-positive referrals, even with an accurate test. In the future, targeted screening of a population subset with a higher prevalence of glaucoma may be effective. Recent developments in POAG polygenic risk prediction and deep learning image analysis offer potential avenues to identifying glaucoma-enriched sub-populations. Until such time, opportunistic case finding through General Ophthalmic Services remains the primary route for identification of glaucoma in the UK and greater public awareness of the service would be of benefit., (© 2021. The Author(s).)

Aim: The aim of this study was to identify barriers and enablers of diabetic eye screening (DES) attendance amongst young adults with diabetes living in the United Kingdom., Methods: Semistructured qualitative interviews with adults aged 18-34 years with diabetes. Participants were purposively sampled to aim for representation across gender, geographical locations, diabetes type, years since diabetes diagnosis and patterns of attendance (i.e. regular attenders, occasional non-attenders, regular non-attenders). Data were collected and analysed using the Theoretical Domains Framework (TDF) to explore potential individual, sociocultural and environmental influences on attendance. Data were analysed using a combined deductive and inductive thematic analysis approach. Barriers/enablers were mapped to behaviour change techniques (BCTs) to identify potential strategies to increase attendance., Results: Key barriers to attendance reported by the sample of 29 study participants with type 1 diabetes, fell within the TDF domains: [Knowledge] (e.g. not understanding reasons for attending DES or treatments available if diabetic retinopathy is detected), [Social Influences] (e.g. lack of support following DES results), [Social role and Identity] (e.g. not knowing other people their age with diabetes, feeling 'isolated' and being reluctant to disclose their diabetes) and [Environmental Context and Resources] (e.g. lack of appointment flexibility and options for rescheduling). Enablers included: [Social Influences] (e.g. support of family/diabetes team), [Goals] (e.g. DES regarded as 'high priority'). Many of the reported barriers/enablers were consistent across groups. Potential BCTs to support attendance include Instructions on how to perform the behaviour; Information about health consequences; Social support (practical) and Social comparison., Conclusions: Attendance to diabetic eye screening in young adults is influenced by a complex set of interacting factors. Identification of potentially modifiable target behaviours provides a basis for designing more effective, tailored interventions to help young adults regularly attend eye screening and prevent avoidable vision loss., (© 2021 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.)

Purpose: To examine the efficacy and safety of corneal cross-linking (CXL) for stabilization of progressive keratoconus., Design: Observer-masked, randomized, controlled, parallel-group superiority trial., Participants: Sixty participants 10 to 16 years of age with progressive keratoconus, one eye of each deemed the study eye., Methods: The study eye was randomized to either CXL plus standard care or standard care alone, with spectacle or contact lens correction as necessary for vision., Main Outcome Measures: The primary outcome was steep keratometry (K2) in the study eye as a measure of the steepness of the cornea at 18 months. Secondary outcomes included keratoconus progression defined as a 1.5-diopter (D) increase in K2, visual acuity, keratoconus apex corneal thickness, and quality of life., Results: Of 60 participants, 30 were randomized to CXL and standard care groups. Of these, 30 patients in the CXL group and 28 patients in the standard care group were analyzed. Mean K2 in the study eye 18 months after randomization was 49.7 D (standard deviation [SD], 3.8 D) in the CXL group and 53.4 D (SD, 5.8 D) in the standard care group. The adjusted mean difference in K2 in the study eye was -3.0 D (95% confidence interval [CI], -4.9 to -1.1 D; P = 0.002), favoring CXL. Adjusted differences between groups in uncorrected and corrected vision favored eyes receiving CXL: -0.31 logarithm of the minimum angle of resolution (logMAR; 95% CI, -0.50 to -0.11 logMAR; P = 0.002) and -0.51 logMAR (95% CI, -1.37 to 0.35 logMAR; P = 0.002). Keratoconus progression in the study eye occurred in 2 patients (7%) randomized to CXL compared with 12 patients (43%) randomized to standard care. The unadjusted odds ratio suggests that on average, patients in the CXL arm had 90% (odds ratio, 0.1; 95% CI, 0.02-0.48; P = 0.004) lower odds of experiencing progression compared with those receiving standard care., Conclusions: CXL arrests progression of keratoconus in the majority of young patients. CXL should be considered as a first-line treatment in progressive disease. If the arrest of keratoconus progression induced by CXL is sustained in longer follow-up, particular benefit may be derived from avoiding a later requirement for contact lens wear or corneal transplantation., (Copyright © 2021 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Introduction: Diabetic retinopathy screening (DRS) attendance in young adults is consistently below recommended levels. The aim of this study was to conduct a survey of screening providers in the UK Diabetic Eye Screening Programme (DESP) to identify perceived barriers and enablers to DRS attendance in young adults and elicit views on the effectiveness of strategies to improve screening uptake in this population., Research Design and Methods: Members of the British Association of Retinal Screening (n=580) were invited to complete an anonymous online survey in July 2020 assessing agreement with 37 belief statements, informed by the Theoretical Domains Framework (TDF) of behavior change, describing potential barrier/enablers to delivering DRS for young adults and further survey items exploring effectiveness of strategies to improve uptake of DRS., Results: In total, 140 (24%) responses were received mostly from screener/graders (67.1%). There was a high level of agreement that the DESP had a role in improving attendance in young adults (96.4%) and that more could be done to improve attendance (90.0%). The most commonly reported barriers related to TDF domains Social influences and Environmental context and resources including lack of integration of DRS with other processes of diabetes care, which limited the ability to discuss diabetes self-management. Other barriers included access to screening services and difficulties with scheduling appointments. Less than half (46.4%) of respondents reported having a dedicated strategy to improve screening uptake in young adults. Strategies perceived to be effective included: screening within the community; prompts/reminders and integrating eye screening with other diabetes services., Conclusions: Screening providers were concerned about screening uptake in young adults, although many programs lacked a dedicated strategy to improve attendance. Problems associated with a lack of integration between DRS with other diabetes care processes were identified as a major barrier to providing holistic care to young adults and supporting diabetes self-management., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Background: Cataract surgery is one of the most common operations. Femtosecond laser-assisted cataract surgery (FLACS) is a technique that automates a number of operative steps., Objectives: To compare FLACS with phacoemulsification cataract surgery (PCS)., Design: Multicentre, outcome-masked, randomised controlled non-inferiority trial., Setting: Three collaborating NHS hospitals., Participants: A total of 785 patients with age-related cataract in one or both eyes were randomised between May 2015 and September 2017., Intervention: FLACS ( n = 392 participants) or PCS ( n = 393 participants)., Main Outcome Measures: The primary outcome was uncorrected distance visual acuity in the study eye after 3 months, expressed as the logarithm of the minimum angle of resolution (logMAR): 0.00 logMAR (or 6/6 if expressed in Snellen) is normal (good visual acuity). Secondary outcomes included corrected distance visual acuity, refractive outcomes (within 0.5 dioptre and 1.0 dioptre of target), safety and patient-reported outcome measures at 3 and 12 months, and resource use. All trial follow-ups were performed by optometrists who were masked to the trial intervention., Results: A total of 353 (90%) participants allocated to the FLACS arm and 317 (81%) participants allocated to the PCS arm attended follow-up at 3 months. The mean uncorrected distance visual acuity was similar in both treatment arms [0.13 logMAR, standard deviation 0.23 logMAR, for FLACS, vs. 0.14 logMAR, standard deviation 0.27 logMAR, for PCS, with a difference of -0.01 logMAR (95% confidence interval -0.05 to 0.03 logMAR; p  = 0.63)]. The mean corrected distance visual acuity values were again similar in both treatment arms (-0.01 logMAR, standard deviation 0.19 logMAR FLACS vs. 0.01 logMAR, standard deviation 0.21 logMAR PCS; p  = 0.34). There were two posterior capsule tears in the PCS arm. There were no significant differences between the treatment arms for any secondary outcome at 3 months. At 12 months, the mean uncorrected distance visual acuity was 0.14 logMAR (standard deviation 0.22 logMAR) for FLACS and 0.17 logMAR (standard deviation 0.25 logMAR) for PCS, with a difference between the treatment arms of -0.03 logMAR (95% confidence interval -0.06 to 0.01 logMAR; p  = 0.17). The mean corrected distance visual acuity was 0.003 logMAR (standard deviation 0.18 logMAR) for FLACS and 0.03 logMAR (standard deviation 0.23 logMAR) for PCS, with a difference of -0.03 logMAR (95% confidence interval -0.06 to 0.01 logMAR; p  = 0.11). There were no significant differences between the arms for any other outcomes, with the exception of the mean binocular corrected distance visual acuity with a difference of -0.02 logMAR (95% confidence interval -0.05 to 0.00 logMAR) ( p  = 0.036), which favoured FLACS. There were no significant differences between the arms for any health, social care or societal costs. For the economic evaluation, the mean cost difference was £167.62 per patient higher for FLACS (95% of iterations between -£14.12 and £341.67) than for PCS. The mean QALY difference (FLACS minus PCS) was 0.001 (95% of iterations between -0.011 and 0.015), which equates to an incremental cost-effectiveness ratio (cost difference divided by QALY difference) of £167,620., Limitations: Although the measurement of outcomes was carried out by optometrists who were masked to the treatment arm, the participants were not masked., Conclusions: The evidence suggests that FLACS is not inferior to PCS in terms of vision after 3 months' follow-up, and there were no significant differences in patient-reported health and safety outcomes after 12 months' follow-up. In addition, the statistically significant difference in binocular corrected distance visual acuity was not clinically significant. FLACS is not cost-effective., Future Work: To explore the possible differences in vision in patients without ocular co-pathology., Trial Registration: Current Controlled Trials ISRCTN77602616., Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment ; Vol. 25, No. 6. See the NIHR Journals Library website for further project information. Moorfields Eye Charity (grant references GR000233 and GR000449 for the endothelial cell counter and femtosecond laser used).

Purpose: To report the 1-year outcomes of a randomized trial comparing femtosecond laser-assisted cataract surgery (FLACS) and phacoemulsification cataract surgery (PCS)., Setting: Moorfields Eye Hospital, New Cross Hospital, and Sussex Eye Hospital, United Kingdom., Design: Multicenter, randomized controlled noninferiority trial., Methods: Patients undergoing cataract surgery were randomized to FLACS or PCS. Postoperative assessments were masked. Outcomes included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), complications, corneal endothelial cell count, and patient-reported outcomes measures., Results: The study enrolled 785 participants. A total of 311 of 392 (79%) participants were allocated to FLACS and 292 of 393 (74%) participants were allocated to PCS attended follow-up at 1 year. Mean UDVA was 0.14 (SD = 0.22) for FLACS and 0.17 (0.25) for PCS with difference of -0.03 logarithm of the minimum angle of resolution (logMAR) (95%, -0.06 to 0.01, P = .17). Mean CDVA was 0.003 (0.18) for FLACS and 0.03 (0.23) for PCS with difference of -0.03 logMAR (95% CI, -0.06 to 0.01, P = .11); 75% of both FLACS (230/307) and PCS (218/290) cases were within ±0.5 diopters (D) refractive target, and 292 (95%) of 307 eyes of FLACS and 279 (96%) of 290 eyes of PCS groups were within ±1.0 D. There were no significant differences between arms for all other outcomes with the exception of binocular CDVA mean difference -0.02 (-0.05 to 0.002) logMAR (P = .036) favoring FLACS. Mean cost difference was £167.62 per patient greater for FLACS (95% iterations between -£14.12 and £341.67)., Conclusions: PCS is not inferior to FLACS regarding vision, patient-reported health, and safety outcomes after 1-year follow-up. A difference was found for binocular CDVA, which, although statistically significant, was not clinically important. FLACS was not cost-effective.

Purpose: To report the 3-month results of a randomized trial (Femtosecond Laser-Assisted Cataract Trial [FACT]) comparing femtosecond laser-assisted cataract surgery (FLACS) with standard phacoemulsification cataract surgery (PCS)., Design: Multicenter, randomized controlled trial funded by the UK National Institute of Health Research (HTA 13/04/46/)., Participants: Seven hundred eighty-five patients with age-related cataract., Methods: This trial took place in 3 hospitals in the UK National Health Service (NHS). Randomization (1:1) was stratified by site, surgeon, and 1 or both eyes eligible using a secure web-based system. Postoperative assessments were masked to the allocated intervention. The primary outcome was unaided distance visual acuity (UDVA) in the study eye at 3 months. Secondary outcomes included corrected distance visual acuity, complications, and patient-reported outcomes measures. The noninferiority margin was 0.1 logarithm of the minimum angle of resolution (logMAR). ISRCTN.com registry, number ISRCTN77602616., Main Outcome Measures: We enrolled 785 participants between May 2015 and September 2017 and randomly assigned 392 to FLACS and 393 to PCS. At 3 months postoperatively, mean UDVA difference between treatment arms was -0.01 logMAR (-0.05 to 0.03), and mean corrected distance visual acuity difference was -0.01 logMAR (95% confidence interval [CI], -0.05 to 0.02). Seventy-one percent of both FLACS and PCS cases were within ±0.5 diopters (D) of the refractive target, and 93% of FLACS and 92% of PCS cases were within ±1.0 D. There were 2 posterior capsule tears in the PCS arm and none in the FLACS arm. There were no significant differences between arms for any secondary outcome., Conclusions: Femtosecond laser-assisted cataract surgery is not inferior to conventional PCS surgery 3 months after surgery. Both methods are as good in terms of vision, patient-reported health, and safety outcomes at 3 months. Longer-term outcomes of the clinical effectiveness and cost-effectiveness are awaited., (Copyright © 2020 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Introduction: The KERALINK trial tests the hypothesis that corneal cross-linking (CXL) treatment reduces the progression of keratoconus in comparison to standard care in patients under 17 years old. KERALINK is a randomised controlled, observer-masked, multicentre trial in progressive keratoconus comparing epithelium-off CXL with standard care, including spectacles or contact lenses as necessary for best-corrected acuity., Methods and Analysis: A total of 30 participants will be randomised per group. Eligible participants aged 10-16 years with progressive keratoconus in one or both eyes will be recruited. Following randomisation, participants will be followed up 3-monthly for 18 months. The effect on progression will be determined by K 2 on corneal topography. The primary outcome measure is between-group difference in K 2 at 18 months adjusted for K 2 at baseline examination. Secondary outcomes are the effect of CXL on (1) keratoconus progression, (2) time to keratoconus progression, (3) visual acuity, (4) refraction, (5) apical corneal thickness and (6) adverse events. Patient-reported effects will be explored by questionnaires., Ethics and Dissemination: Research Ethics Committee Approval was obtained on 30 June 2016 (ref: 14/LO/1937). Current protocol: V.5.0 (08/11/2017). Study findings will be published in peer-reviewed journals., Trial Registration Number: European Union clinial trials register (EudraCT) 2016-001460-11., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)

Background: Endovenous laser ablation and ultrasound-guided foam sclerotherapy are recommended alternatives to surgery for the treatment of primary varicose veins, but their long-term comparative effectiveness remains uncertain., Methods: In a randomized, controlled trial involving 798 participants with primary varicose veins at 11 centers in the United Kingdom, we compared the outcomes of laser ablation, foam sclerotherapy, and surgery. Primary outcomes at 5 years were disease-specific quality of life and generic quality of life, as well as cost-effectiveness based on models of expected costs and quality-adjusted life-years (QALYs) gained that used data on participants' treatment costs and scores on the EuroQol EQ-5D questionnaire., Results: Quality-of-life questionnaires were completed by 595 (75%) of the 798 trial participants. After adjustment for baseline scores and other covariates, scores on the Aberdeen Varicose Vein Questionnaire (on which scores range from 0 to 100, with lower scores indicating a better quality of life) were lower among patients who underwent laser ablation or surgery than among those who underwent foam sclerotherapy (effect size [adjusted differences between groups] for laser ablation vs. foam sclerotherapy, -2.86; 95% confidence interval [CI], -4.49 to -1.22; P<0.001; and for surgery vs. foam sclerotherapy, -2.60; 95% CI, -3.99 to -1.22; P<0.001). Generic quality-of-life measures did not differ among treatment groups. At a threshold willingness-to-pay ratio of £20,000 ($28,433 in U.S. dollars) per QALY, 77.2% of the cost-effectiveness model iterations favored laser ablation. In a two-way comparison between foam sclerotherapy and surgery, 54.5% of the model iterations favored surgery., Conclusions: In a randomized trial of treatments for varicose veins, disease-specific quality of life 5 years after treatment was better after laser ablation or surgery than after foam sclerotherapy. The majority of the probabilistic cost-effectiveness model iterations favored laser ablation at a willingness-to-pay ratio of £20,000 ($28,433) per QALY. (Funded by the National Institute for Health Research; CLASS Current Controlled Trials number, ISRCTN51995477.)., (Copyright © 2019 Massachusetts Medical Society.)

Aims: To identify and synthesize studies reporting modifiable barriers/enablers associated with retinopathy screening attendance in people with Type 1 or Type 2 diabetes, and to identify those most likely to influence attendance., Methods: We searched MEDLINE, EMBASE, PsycINFO, Cochrane Library and the 'grey literature' for quantitative and qualitative studies to February 2017. Data (i.e. participant quotations, interpretive summaries, survey results) reporting barriers/enablers were extracted and deductively coded into domains from the Theoretical Domains Framework; with domains representing categories of theoretical barriers/enablers proposed to mediate behaviour change. Inductive thematic analysis was conducted within domains to describe the role each domain plays in facilitating or hindering screening attendance. Domains that were more frequently coded and for which more themes were generated were judged more likely to influence attendance., Results: Sixty-nine primary studies were included. We identified six theoretical domains ['environmental context and resources' (75% of included studies), 'social influences' (51%), 'knowledge' (51%), 'memory, attention, decision processes' (50%), 'beliefs about consequences' (38%) and 'emotions' (33%)] as the key mediators of diabetic retinopathy screening attendance. Examples of barriers populating these domains included inaccurate diabetic registers and confusion between routine eye care and retinopathy screening. Recommendations by healthcare professionals and community-level media coverage acted as enablers., Conclusions: Across a variety of contexts, we found common barriers to and enablers of retinopathy screening that could be targeted in interventions aiming to increase screening attendance., (© 2018 Diabetes UK.)

Background: Presentation with advanced glaucoma is the major risk factor for lifetime blindness. Effective intervention at diagnosis is expected to minimise risk of further visual loss in this group of patients., Aim: To compare clinical and cost-effectiveness of primary medical management compared with primary surgery for people presenting with advanced open-angle glaucoma (OAG)., Methods: Design : A prospective, pragmatic multicentre randomised controlled trial (RCT)., Setting: Twenty-seven UK hospital eye services., Participants: Four hundred and forty patients presenting with advanced OAG, according to the Hodapp-Parish-Anderson classification of visual field loss., Intervention: Participants will be randomised to medical treatment or augmented trabeculectomy (1:1 allocation minimised by centre and presence of advanced disease in both eyes)., Main Outcome Measures: The primary outcome is vision-related quality of life measured by the National Eye Institute-Visual Function Questionnaire-25 at 24 months. Secondary outcomes include generic EQ-5D-5L, Health Utility Index-3 and glaucoma-related health status (Glaucoma Utility Index), patient experience, visual field measured by mean deviation value, logarithm of the mean angle of resolution visual acuity, intraocular pressure, adverse events, standards for driving and eligibility for blind certification. Incremental cost per quality-adjusted life-year (QALY) based on EQ-5D-5L and glaucoma profile instrument will be estimated., Results: The study will report the comparative effectiveness and cost-effectiveness of medical treatment against augmented trabeculectomy in patients presenting with advanced glaucoma in terms of patient-reported health and visual function, clinical outcomes and incremental cost per QALY at 2 years., Conclusions: Treatment of Advanced Glaucoma Study will be the first RCT reporting outcomes from the perspective of those with advanced glaucoma., Trial Registration Number: ISRCTN56878850, Pre-results., Competing Interests: Competing interests: TAGS is funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA) programme (project number 12/35/38). JMB, GM, AM and JMS report grants from NIHR Health Technology Assessment Programme during the conduct of the study. LV reports grants from NIHR HTA Programme during the conduct of the study; and membership of the NIHR Health Technology Assessment Programme and a director of the NIHR Research Design Service. JN reports grants from NIHR HTA during the conduct of the study; personal fees from NIHR Editors Board, other from NIHR HTA General Board, outside the submitted work., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: Diabetic retinopathy screening (DRS) is effective but uptake is suboptimal., Objectives: To determine the effectiveness of quality improvement (QI) interventions for DRS attendance; describe the interventions in terms of QI components and behaviour change techniques (BCTs); identify theoretical determinants of attendance; investigate coherence between BCTs identified in interventions and determinants of attendance; and determine the cost-effectiveness of QI components and BCTs for improving DRS., Data Sources and Review Methods: Phase 1 - systematic review of randomised controlled trials (RCTs) evaluating interventions to increase DRS attendance (The Cochrane Library, MEDLINE, EMBASE and trials registers to February 2017) and coding intervention content to classify QI components and BCTs. Phase 2 - review of studies reporting factors influencing attendance, coded to theoretical domains (MEDLINE, EMBASE, PsycINFO and sources of grey literature to March 2016). Phase 3 - mapping BCTs (phase 1) to theoretical domains (phase 2) and an economic evaluation to determine the cost-effectiveness of BCTs or QI components., Results: Phase 1 - 7277 studies were screened, of which 66 RCTs were included in the review. Interventions were multifaceted and targeted patients, health-care professionals (HCPs) or health-care systems. Overall, interventions increased DRS attendance by 12% [risk difference (RD) 0.12, 95% confidence interval (CI) 0.10 to 0.14] compared with usual care, with substantial heterogeneity in effect size. Both DRS-targeted and general QI interventions were effective, particularly when baseline attendance levels were low. All commonly used QI components and BCTs were associated with significant improvements, particularly in those with poor attendance. Higher effect estimates were observed in subgroup analyses for the BCTs of 'goal setting (outcome, i.e. consequences)' (RD 0.26, 95% CI 0.16 to 0.36) and 'feedback on outcomes (consequences) of behaviour' (RD 0.22, 95% CI 0.15 to 0.29) in interventions targeting patients and of 'restructuring the social environment' (RD 0.19, 95% CI 0.12 to 0.26) and 'credible source' (RD 0.16, 95% CI 0.08 to 0.24) in interventions targeting HCPs. Phase 2 - 3457 studies were screened, of which 65 non-randomised studies were included in the review. The following theoretical domains were likely to influence attendance: 'environmental context and resources', 'social influences', 'knowledge', 'memory, attention and decision processes', 'beliefs about consequences' and 'emotions'. Phase 3 - mapping identified that interventions included BCTs targeting important barriers to/enablers of DRS attendance. However, BCTs targeting emotional factors around DRS were under-represented. QI components were unlikely to be cost-effective whereas BCTs with a high probability (≥ 0.975) of being cost-effective at a societal willingness-to-pay threshold of £20,000 per QALY included 'goal-setting (outcome)', 'feedback on outcomes of behaviour', 'social support' and 'information about health consequences'. Cost-effectiveness increased when DRS attendance was lower and with longer screening intervals., Limitations: Quality improvement/BCT coding was dependent on descriptions of intervention content in primary sources; methods for the identification of coherence of BCTs require improvement., Conclusions: Randomised controlled trial evidence indicates that QI interventions incorporating specific BCT components are associated with meaningful improvements in DRS attendance compared with usual care. Interventions generally used appropriate BCTs that target important barriers to screening attendance, with a high probability of being cost-effective. Research is needed to optimise BCTs or BCT combinations that seek to improve DRS attendance at an acceptable cost. BCTs targeting emotional factors represent a missed opportunity to improve attendance and should be tested in future studies., Study Registration: This study is registered as PROSPERO CRD42016044157 and PROSPERO CRD42016032990., Funding: The National Institute for Health Research Health Technology Assessment programme., Competing Interests: Luke Vale is a member of the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Clinical Evaluation and Trials Board. Noah M Ivers received grants from the Canadian Institutes of Health Research outside the submitted work. Jeremy M Grimshaw received grants from the Canadian Institutes of Health Research during the conduct of this study.

Objective: To assess the efficiency of alternative monitoring services for people with ocular hypertension (OHT), a glaucoma risk factor., Design: Discrete event simulation model comparing five alternative care pathways: treatment at OHT diagnosis with minimal monitoring; biennial monitoring (primary and secondary care) with treatment if baseline predicted 5-year glaucoma risk is ≥6%; monitoring and treatment aligned to National Institute for Health and Care Excellence (NICE) glaucoma guidance (conservative and intensive)., Setting: UK health services perspective., Participants: Simulated cohort of 10 000 adults with OHT (mean intraocular pressure (IOP) 24.9 mm Hg (SD 2.4)., Main Outcome Measures: Costs, glaucoma detected, quality-adjusted life years (QALYs)., Results: Treating at diagnosis was the least costly and least effective in avoiding glaucoma and progression. Intensive monitoring following NICE guidance was the most costly and effective. However, considering a wider cost-utility perspective, biennial monitoring was less costly and provided more QALYs than NICE pathways, but was unlikely to be cost-effective compared with treating at diagnosis (£86 717 per additional QALY gained). The findings were robust to risk thresholds for initiating monitoring but were sensitive to treatment threshold, National Health Service costs and treatment adherence., Conclusions: For confirmed OHT, glaucoma monitoring more frequently than every 2 years is unlikely to be efficient. Primary treatment and minimal monitoring (assessing treatment responsiveness (IOP)) could be considered; however, further data to refine glaucoma risk prediction models and value patient preferences for treatment are needed. Consideration to innovative and affordable service redesign focused on treatment responsiveness rather than more glaucoma testing is recommended., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Purpose: To compare the diagnostic performance of automated imaging for glaucoma., Design: Prospective, direct comparison study., Participants: Adults with suspected glaucoma or ocular hypertension referred to hospital eye services in the United Kingdom., Methods: We evaluated 4 automated imaging test algorithms: the Heidelberg Retinal Tomography (HRT; Heidelberg Engineering, Heidelberg, Germany) glaucoma probability score (GPS), the HRT Moorfields regression analysis (MRA), scanning laser polarimetry (GDx enhanced corneal compensation; Glaucoma Diagnostics (GDx), Carl Zeiss Meditec, Dublin, CA) nerve fiber indicator (NFI), and Spectralis optical coherence tomography (OCT; Heidelberg Engineering) retinal nerve fiber layer (RNFL) classification. We defined abnormal tests as an automated classification of outside normal limits for HRT and OCT or NFI ≥ 56 (GDx). We conducted a sensitivity analysis, using borderline abnormal image classifications. The reference standard was clinical diagnosis by a masked glaucoma expert including standardized clinical assessment and automated perimetry. We analyzed 1 eye per patient (the one with more advanced disease). We also evaluated the performance according to severity and using a combination of 2 technologies., Main Outcome Measures: Sensitivity and specificity, likelihood ratios, diagnostic, odds ratio, and proportion of indeterminate tests., Results: We recruited 955 participants, and 943 were included in the analysis. The average age was 60.5 years (standard deviation, 13.8 years); 51.1% were women. Glaucoma was diagnosed in at least 1 eye in 16.8%; 32% of participants had no glaucoma-related findings. The HRT MRA had the highest sensitivity (87.0%; 95% confidence interval [CI], 80.2%-92.1%), but lowest specificity (63.9%; 95% CI, 60.2%-67.4%); GDx had the lowest sensitivity (35.1%; 95% CI, 27.0%-43.8%), but the highest specificity (97.2%; 95% CI, 95.6%-98.3%). The HRT GPS sensitivity was 81.5% (95% CI, 73.9%-87.6%), and specificity was 67.7% (95% CI, 64.2%-71.2%); OCT sensitivity was 76.9% (95% CI, 69.2%-83.4%), and specificity was 78.5% (95% CI, 75.4%-81.4%). Including only eyes with severe glaucoma, sensitivity increased: HRT MRA, HRT GPS, and OCT would miss 5% of eyes, and GDx would miss 21% of eyes. A combination of 2 different tests did not improve the accuracy substantially., Conclusions: Automated imaging technologies can aid clinicians in diagnosing glaucoma, but may not replace current strategies because they can miss some cases of severe glaucoma., (Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.)

Introduction: Cataract is one of the leading causes of low vision in the westernised world, and cataract surgery is one of the most commonly performed operations. Laser platforms for cataract surgery are now available, the anticipated advantages of which are broad and may include better visual outcomes through greater precision and reproducibility, and improved safety. FACT is a randomised single masked non-inferiority trial to establish whether laser-assisted cataract surgery is as good as or better than standard manual phacoemulsification., Methods and Analysis: 808 patients aged 18 years and over with visually significant cataract will be randomised to manual phacoemulsification cataract surgery (standard care) or laser-assisted cataract surgery (intervention arm). Outcomes will be measured at 3 and 12 months after surgery. The primary clinical outcome is uncorrected distance visual acuity (UDVA, logMAR) at 3 months in the study eye recorded by an observer masked to the trial group. Secondary outcomes include UDVA at 12 months, corrected distance visual acuity at 3 and 12 months, complications, endothelial cell loss, patient-reported outcome measures and a health economic analysis conforming to National Institute for Health and Care Excellence standards., Ethics and Dissemination: Research Ethics Committee Approval was obtained on 6 February 2015, ref: 14/LO/1937. Current protocol: v2.0 (08/04/2015). Study findings will be published in peer-reviewed journals., Isrctn: 77602616., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Topic: To compare the accuracy of optical coherence tomography (OCT) with alternative tests for monitoring neovascular age-related macular degeneration (nAMD) and detecting disease activity among eyes previously treated for this condition., Clinical Relevance: Traditionally, fundus fluorescein angiography (FFA) has been considered the reference standard to detect nAMD activity, but FFA is costly and invasive. Replacement of FFA by OCT can be justified if there is a substantial agreement between tests., Methods: Systematic review and meta-analysis. The index test was OCT. The comparator tests were visual acuity, clinical evaluation (slit lamp), Amsler chart, color fundus photographs, infrared reflectance, red-free images and blue reflectance, fundus autofluorescence imaging, indocyanine green angiography (ICGA), preferential hyperacuity perimetry, and microperimetry. We searched the following databases: MEDLINE, MEDLINE In-Process, EMBASE, Biosis, Science Citation Index, the Cochrane Library, Database of Abstracts of Reviews of Effects, MEDION, and the Health Technology Assessment database. The last literature search was conducted in March 2013. We used the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) to assess risk of bias., Results: We included 8 studies involving more than 400 participants. Seven reported the performance of OCT (3 time-domain [TD] OCT, 3 spectral-domain [SD] OCT, 1 both types) and 1 reported the performance of ICGA in the detection of nAMD activity. We did not find studies directly comparing tests in the same population. The pooled sensitivity and specificity of TD OCT and SD OCT for detecting active nAMD was 85% (95% confidence interval [CI], 72%-93%) and 48% (95% CI, 30%-67%), respectively. One study reported ICGA with sensitivity of 75.9% and specificity of 88.0% for the detection of active nAMD. Half of the studies were considered to have a high risk of bias., Conclusions: There is substantial disagreement between OCT and FFA findings in detecting active disease in patients with nAMD who are being monitored. Both methods may be needed to monitor patients comprehensively with nAMD., (Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.)

Unlabelled: The purpose is to study the diagnostic performance of optical coherence tomography (OCT) and alternative diagnostic tests for neovascular age-related macular degeneration (nAMD). Methods employed are as follows:systematic review and meta-analysis;, Index Test: OCT including time-domain (TD-OCT) and the most recently developed spectral domain (SD-OCT); comparator tests: visual acuity, clinical evaluation (slit lamp), Amsler chart, colour fundus photographs, infra-red reflectance, red-free images/blue reflectance, fundus autofluorescence imaging (FAF), indocyanine green angiography (ICGA), preferential hyperacuity perimetry (PHP), and microperimetry; reference standard: fundus fluorescein angiography. Databases searched included MEDLINE, MEDLINE In Process, EMBASE, Biosis, SCI, the Cochrane Library, DARE, MEDION, and HTA database. Last literature searches: March 2013. Risk of bias assessed using QUADAS-2. Meta-analysis models were fitted using hierarchical summary receiver operating characteristic (HSROC) curves. Twenty-two studies (2 abstracts and 20 articles) enrolling 2124 participants were identified, reporting TD-OCT (12 studies), SD-OCT (1 study), ICGA (8 studies), PHP (3 studies), Amsler grid, colour fundus photography and FAF (1 study each). Most studies were considered to have a high risk of bias in the patient selection (55%, 11/20), and flow and timing (40%, 8/20) domains. In a meta-analysis of TD-OCT studies, sensitivity and specificity (95% CI) were 88% (46-98%) and 78% (64-88%), respectively. There was insufficient information to undertake meta-analysis for other tests. TD-OCT is a sensitive test for detecting nAMD, although specificity was only moderate. Data on SD-OCT are sparse. Diagnosis of nAMD should not rely solely on OCT.

Background: The treatment of patients with varicose veins constitutes a considerable workload and financial burden to the National Health Service. This study aimed to assess the cost-effectiveness of ultrasound-guided foam sclerotherapy (UGFS) and endovenous laser ablation (EVLA) compared with conventional surgery as treatment for primary varicose veins., Methods: Participant cost and utility data were collected alongside the UK CLASS multicentre randomized clinical trial, which compared EVLA, surgery and UGFS. Regression methods were used to estimate the effects of the alternative treatments on costs to the health service and quality-adjusted life-years (QALYs) at 6 months. A Markov model, incorporating available evidence on clinical recurrence rates, was developed to extrapolate the trial data over a 5-year time horizon., Results: Compared with surgery at 6 months, UGFS and EVLA reduced mean costs to the health service by £655 and £160 respectively. When additional overhead costs associated with theatre use were included, these cost savings increased to £902 and £392 respectively. UGFS produced 0·005 fewer QALYs, whereas EVLA produced 0·011 additional QALYs. Extrapolating to 5 years, EVLA was associated with increased costs and QALYs compared with UGFS (costing £3640 per QALY gained), and generated a cost saving (£206-439) and QALY gain (0·078) compared with surgery. Applying a ceiling willingness-to-pay ratio of £20 000 per QALY gained, EVLA had the highest probability (78·7 per cent) of being cost-effective., Conclusion: The results suggest, for patients considered eligible for all three treatment options, that EVLA has the highest probability of being cost-effective at accepted thresholds of willingness to pay per QALY., (© 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.)

Clinical outcomes, such as quantifying the extent of visual field loss by automated perimetry, are valued highly by health professionals, but such measures do not capture the impact of the condition on a patient's life. Patient-reported outcomes describe any report or measure of health reported by the patient, without external interpretation by a clinician or researcher. In this review, we discuss the value of the measures that capture this information (patient-reported outcome measures; PROMs), and why they are important to both the clinician and the researcher. We also consider issues around developing or selecting a PROM for ophthalmic research, the emerging challenges around conducting and reporting PROMs in clinical trials and highlight best practice for their use. Search terms for this review comprised: (1) (patient-reported outcomes OR patient-reported outcome measures) AND (2) randomised controlled trials AND (3) limited to ophthalmic conditions. These terms were expanded as follows: ((('patients'(MeSH Terms) OR 'patients'(All Fields) OR 'patient'(All Fields)) AND ('research report'(MeSH Terms) OR ('research'(All Fields) AND 'report'(All Fields)) OR 'research report'(All Fields) OR 'reported'(All Fields)) AND outcomes(All Fields)) OR (('patients'(MeSH Terms) OR 'patients'(All Fields) OR 'patient'(All Fields)) AND ('research report'(MeSH Terms) OR ('research'(All Fields) AND 'report'(All Fields)) OR 'research report'(All Fields) OR 'reported'(All Fields) AND ('outcome assessment (health care)'(MeSH Terms) OR ('outcome'(All Fields) AND 'assessment'(All Fields) AND '(health'(All Fields) AND 'care)'(All Fields)) OR 'outcome assessment (health care)'(All Fields) OR ('outcome'(All Fields) AND 'measures'(All Fields)) OR 'outcome measures'(All Fields)))) AND ('randomized controlled trial'(Publication Type) OR 'randomized controlled trials as topic'(MeSH Terms) OR 'randomised controlled trials'(All Fields) OR 'randomized controlled trials'(All Fields)) AND (ophth*(All Fields)). The authors also utilised the extensive non-ophthalmic literature and online resources relating to PROs and PROMs to inform this review.

Aims: To independently evaluate and compare the performance of the Ocular Hypertension Treatment Study-European Glaucoma Prevention Study (OHTS-EGPS) prediction equation for estimating the 5-year risk of open-angle glaucoma (OAG) in four cohorts of adults with ocular hypertension., Methods: Data from two randomised controlled trials and two observational studies were analysed individually to assess transferability of the prediction equation between different geographical locations and settings. To make best use of the data and to avoid bias, missing predictor values were imputed using multivariate imputation by chained equations. Using the OHTS-EGPS risk prediction equation, predicted risk was calculated for each patient in each cohort. We used the c-index, calibration plot and calibration slope to evaluate predictive ability of the equation., Results: Analyses were based on 393, 298, 188 and 159 patients for the Rotterdam, Moorfields, Dunfermline, and Nottingham cohorts, respectively. The discriminative ability was good, with c-indices between 0.69 and 0.83. In calibration analyses, the risk of OAG was generally overestimated, although for the Rotterdam cohort the calibration slope was close to 1 (1.09, 95% CI 0.72 to 1.46), the ideal value when there is perfect agreement between predicted and observed risks., Conclusions: The OHTS-EGPS risk prediction equation has predictive utility, but further validation in a population-based setting is needed.

Objective: To explore the presentation behaviours and pathways to detection of adults who first presented to UK hospital eye services with severe glaucoma., Design: Semistructured interviews, based on models of diagnostic delay, to obtain a descriptive self-reported account of when and how participants' glaucoma was detected., Results: 11 patients participated (five in Aberdeen, six in Huddersfield). Four participants reported that the optometry appointment at which their glaucoma was detected was their first ever eye test or their first for over 10 years. Seven participants reported attending regular routine optometrist appointments. Their self-reported experiences and pathways to detection describe a variety of missed detection opportunities and delayed referral and treatment., Conclusions: The qualitative data suggest that late detection of glaucoma can result from delays at the patient level but, although based on a small sample, delays also occurred at the healthcare provider (system) level both in terms of accuracy of case detection and effective referral. We suggest that current attempts to address the significant burden of over-referral of glaucoma suspects to hospital eye services (a large proportion of which are false positives) must also focus on the issue of false negatives and on reducing missed detection and service delays.

Background: To develop patient-reported outcome instruments, statistical techniques (e.g., principal components analysis; PCA) are used to examine correlations among items and identify interrelated item subsets (empirical factors). However, interpretation and labelling of empirical factors is a subjective process, lacking precision or conceptual basis. We report a novel and reproducible method for mapping between theoretical and empirical factor structures. We illustrate the method using the pilot Aberdeen Glaucoma Questionnaire (AGQ), a new measure of glaucoma-related disability developed using the International Classification of Functioning and Disability (ICF) as a theoretical framework and tested in a sample representing the spectrum of glaucoma severity., Methods: We used the ICF to code AGQ item content before mailing the AGQ to a UK sample (N = 1349) selected to represent people with a risk factor for glaucoma and people with glaucoma across a range of severity. Reflecting uncertainty in the theoretical framework (items with multiple ICF codes), an exploratory PCA was conducted. The theoretical structure informed our interpretation of the empirical structure and guided the selection of theoretically-derived factor labels. We also explored the discrimination of the AGQ across glaucoma severity groups., Results: 656 (49%) completed questionnaires were returned. The data yielded a 7-factor solution with a simple structure (using cut-off point of a loading of 0.5) that together accounted for 63% of variance in the scores. The mapping process resulted in allocation of the following theoretically-derived factor labels: 1) Seeing Functions: Participation; 2) Moving Around & Communication; 3) Emotional Functions; 4) Walking Around Obstacles; 5) Light; 6) Seeing Functions: Domestic & Social Life; 7) Mobility. Using the seven factor scores as independent variables in a discriminant function analysis, the AGQ scores resulted in correct glaucoma severity grading of 32.5% of participants (p < 0.001)., Conclusions: This paper addresses a methodological gap in the application of classical test theory (CTT) techniques, such as PCA, in instrument development. Labels for empirically-derived factors are often selected intuitively whereas they can inform existing bodies of knowledge if selected on the basis of theoretical construct labels, which are more explicitly defined and which relate to each other in ways that are evidence based.

Background: Glaucoma is a leading cause of blindness. Early detection is advocated but there is insufficient evidence from randomized controlled trials (RCTs) to inform health policy on population screening. Primarily, there is no agreed screening intervention. For a screening programme, agreement is required on the screening tests to be used, either individually or in combination, the person to deliver the test and the location where testing should take place. This study aimed to use ophthalmologists (who were experienced glaucoma subspecialists), optometrists, ophthalmic nurses and patients to develop a reduced set of potential screening tests and testing arrangements that could then be explored in depth in a further study of their feasibility for evaluation in a glaucoma screening RCT., Methods: A two-round Delphi survey involving 38 participants was conducted. Materials were developed from a prior evidence synthesis. For round one, after some initial priming questions in four domains, specialists were asked to nominate three screening interventions, the intervention being a combination of the four domains; target population, (age and higher risk groups), site, screening test and test operator (provider). More than 250 screening interventions were identified. For round two, responses were condensed into 72 interventions and each was rated by participants on a 0-10 scale in terms of feasibility., Results: Using a cut-off of a median rating of feasibility of ≥5.5 as evidence of agreement of intervention feasibility, six interventions were identified from round 2. These were initiating screening at age 50, with a combination of two or three screening tests (varying combinations of tonometry/measures of visual function/optic nerve damage) organized in a community setting with an ophthalmic trained technical assistant delivering the tests. An alternative intervention was a 'glaucoma risk score' ascertained by questionnaire. The advisory panel recommended that further exploration of the feasibility of screening higher risk populations and detailed specification of the screening tests was required., Conclusions: With systematic use of expert opinions, a shortlist of potential screening interventions was identified. Views of users, service providers and cost-effectiveness modeling are now required to identify a feasible intervention to evaluate in a future glaucoma screening trial.

Purpose: Patient-reported outcome measures (PROMs) are accepted widely as important outcomes in comparative effectiveness research. Over 30 PROMs have been described for use in glaucoma research, but their role in routine care is undefined. Our study explores the views of patients with glaucoma and their carers on the feasibility and content of a glaucoma PROM for use in day-to-day clinical practice., Methods: Focus groups were held with 71 participants facilitated by 23 staff working in the field of ophthalmology. Comparisons were made among themes derived from this exercise using simple thematic analysis and currently available health-related quality of life (HRQoL) instruments., Results: Participants were supportive of reporting their outcomes if the instrument was short, practical, and useful. Potential barriers to the use of PROMs, including bureaucratic overload and accessibility issues, were identified. Measuring health outcome and patient experience was important to participants. No freely available instrument covers all the domains identified, particularly knowledge and understanding. A novel instrument, a glaucoma patient-reported outcome and experience measure (POEM) is proposed. This addresses three aspects of outcome (fear of blindness, acceptability of treatment/side effects, and impact on daily life), and three aspects of experience (safety, respect, and understanding)., Conclusions: Using PROMs routinely in the management of glaucoma presents significant challenges. Although current instruments (questionnaires) cover many of the participants' key domains, no single instrument covered them all. Further research is required to determine the feasibility (resources required), and validity and reliability of the proposed glaucoma POEM in clinical care.

Objectives: The introduction of new interventional procedures is less regulated than for other health technologies such as pharmaceuticals. Decisions are often taken on evidence of efficacy and short-term safety from small-scale usually observational studies. This reflects the particular challenges of evaluating interventional procedures - the extra facets of skill and training and the difficulty defining a 'new' technology. Currently, there is no framework to evaluate new interventional procedures before they become available in clinical practice as opposed to new pharmaceuticals. This paper proposes a framework to guide the evaluation of a new interventional procedure., Proposed Framework: A framework was developed consisting of a four-stage progressive evaluation for a new interventional procedure: Stage 1: Development; Stage 2: Efficacy and short-term safety; Stage 3: Effectiveness and cost-effectiveness; and Stage 4: Implementation. The framework also suggests the types of studies or data collection methods that can be used to satisfy each stage., Conclusions: This paper makes a first step on a framework for generating evidence on new interventional procedures. The difficulties and limitations of applying such a framework are discussed., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objective: To identify factors associated with intention to attend a hypothetical eye health test and provide an evidence base for developing an intervention to maximise attendance, for use in studies evaluating glaucoma screening programmes., Design: Theory-based cross-sectional survey, based on an extended Theory of Planned Behaviour (TPB) and the Common Sense Self-Regulation Model, conducted in June 2010., Participants: General population including oversampling from low socioeconomic areas., Setting: Aberdeenshire and the London Boroughs of Lewisham and Southwark, UK., Results: From 867 questionnaires posted, 327 completed questionnaires were returned (38%). In hierarchical regression analysis, the three theoretical predictors in the TPB (Attitude, Subjective norm and Perceived Behavioural Control) accounted for two-thirds of the variance in intention scores (adjusted R(2)=0.65). All three predictors contributed significantly to prediction. Adding 'Anticipated regret' as a factor in the TPB model resulted in a significant increase in prediction (adjusted R(2)=0.74). In the Common Sense Self-Regulation Model, only illness representations about the personal consequences of glaucoma (How much do you think glaucoma would affect your life?) and illness concern (How concerned are you about getting glaucoma?) significantly predicted. The final model explained 75% of the variance in intention scores, with ethnicity significantly contributing to prediction., Conclusions: In this population-based sample (including over-representation of lower socioeconomic groupings), the main predictors of intention to attend a hypothetical eye health test were Attitude, Perceived control over attendance, Anticipated regret if did not attend and black ethnicity. This evidence informs the design of a behavioural intervention with intervention components targeting low intentions and predicted to influence health-related behaviours.

Aim: To determine whether internal limiting membrane (ILM) peeling is cost-effective compared with no peeling for patients with an idiopathic stage 2 or 3 full-thickness macular hole., Methods: A cost-effectiveness analysis was performed alongside a randomised controlled trial. 141 participants were randomly allocated to receive macular-hole surgery, with either ILM peeling or no peeling. Health-service resource use, costs and quality of life were calculated for each participant. The incremental cost per quality-adjusted life year (QALY) gained was calculated at 6 months., Results: At 6 months, the total costs were on average higher (£424, 95% CI -182 to 1045) in the No Peel arm, primarily owing to the higher reoperation rate in the No Peel arm. The mean additional QALYs from ILM peel at 6 months were 0.002 (95% CI 0.01 to 0.013), adjusting for baseline EQ-5D and other minimisation factors. A mean incremental cost per QALY was not computed, as Peeling was on average less costly and slightly more effective. A stochastic analysis suggested that there was more than a 90% probability that Peeling would be cost-effective at a willingness-to-pay threshold of £20,000 per QALY., Conclusion: Although there is no evidence of a statistically significant difference in either costs or QALYs between macular hole surgery with or without ILM peeling, the balance of probabilities is that ILM Peeling is likely to be a cost-effective option for the treatment of macular holes. Further long-term follow-up data are needed to confirm these findings.

Purpose: To identify vision Patient-Reported Outcomes instruments relevant to glaucoma and assess their content validity., Methods: MEDLINE, MEDLINE in Process, EMBASE and SCOPUS (to January 2009) were systematically searched. Observational studies or randomised controlled trials, published in English, reporting use of vision instruments in glaucoma studies involving adults were included. In addition, reference lists were scanned to identify additional studies describing development and/or validation to ascertain the final version of the instruments. Instruments' content was then mapped onto a theoretical framework, the World Health Organization International Classification of Functioning, Disability and Health. Two reviewers independently evaluated studies for inclusion and quality assessed instrument content., Results: Thirty-three instruments were identified. Instruments were categorised into thirteen vision status, two vision disability, one vision satisfaction, five glaucoma status, one glaucoma medication related to health status, five glaucoma medication side effects and six glaucoma medication satisfaction measures according to each instruments' content. The National Eye Institute Visual Function Questionnaire-25, Impact of Vision Impairment and Treatment Satisfaction Survey-Intraocular Pressure had the highest number of positive ratings in the content validity assessment., Conclusion: This study provides a descriptive catalogue of vision-specific PRO instruments, to inform the choice of an appropriate measure of patient-reported outcomes in a glaucoma context.

Background: Measures that reflect patients' assessment of their health are of increasing importance as outcome measures in randomised controlled trials. The methodological approach used in the pre-validation development of new instruments (item generation, item reduction and question formatting) should be robust and transparent. The totality of the content of existing PRO instruments for a specific condition provides a valuable resource (pool of items) that can be utilised to develop new instruments. Such 'top down' approaches are common, but the explicit pre-validation methods are often poorly reported. This paper presents a systematic and generalisable 5-step pre-validation PRO instrument methodology., Methods: The method is illustrated using the example of the Aberdeen Glaucoma Questionnaire (AGQ). The five steps are: 1) Generation of a pool of items; 2) Item de-duplication (three phases); 3) Item reduction (two phases); 4) Assessment of the remaining items' content coverage against a pre-existing theoretical framework appropriate to the objectives of the instrument and the target population (e.g. ICF); and 5) qualitative exploration of the target populations' views of the new instrument and the items it contains., Results: The AGQ 'item pool' contained 725 items. Three de-duplication phases resulted in reduction of 91, 225 and 48 items respectively. The item reduction phases discarded 70 items and 208 items respectively. The draft AGQ contained 83 items with good content coverage. The qualitative exploration ('think aloud' study) resulted in removal of a further 15 items and refinement to the wording of others. The resultant draft AGQ contained 68 items., Conclusions: This study presents a novel methodology for developing a PRO instrument, based on three sources: literature reporting what is important to patient; theoretically coherent framework; and patients' experience of completing the instrument. By systematically accounting for all items dropped after the item generation phase, our method ensures that the AGQ is developed in a transparent, replicable manner and is fit for validation. We recommend this method to enhance the likelihood that new PRO instruments will be appropriate to the research context in which they are used, acceptable to research participants and likely to generate valid data.

Background: Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care., Methods/design: EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate., Trial Registration: ISRCTN44464607.

Background: Glaucoma is a leading cause of avoidable blindness worldwide. Open angle glaucoma is the most common type of glaucoma. No randomised controlled trials have been conducted evaluating the effectiveness of glaucoma screening for reducing sight loss. It is unclear what the most appropriate intervention to be evaluated in any glaucoma screening trial would be. The purpose of this study was to develop the clinical components of an intervention for evaluation in a glaucoma (open angle) screening trial that would be feasible and acceptable in a UK eye-care service., Methods: A mixed-methods study, based on the Medical Research Council (MRC) framework for complex interventions, integrating qualitative (semi-structured interviews with 46 UK eye-care providers, policy makers and health service commissioners), and quantitative (economic modelling) methods. Interview data were synthesised and used to revise the screening interventions compared within an existing economic model., Results: The qualitative data indicated broad based support for a glaucoma screening trial to take place in primary care, using ophthalmic trained technical assistants supported by optometry input. The precise location should be tailored to local circumstances. There was variability in opinion around the choice of screening test and target population. Integrating the interview findings with cost-effectiveness criteria reduced 189 potential components to a two test intervention including either optic nerve photography or screening mode perimetry (a measure of visual field sensitivity) with or without tonometry (a measure of intraocular pressure). It would be more cost-effective, and thus acceptable in a policy context, to target screening for open angle glaucoma to those at highest risk but for both practicality and equity arguments the optimal strategy was screening a general population cohort beginning at age forty., Conclusions: Interventions for screening for open angle glaucoma that would be feasible from a service delivery perspective were identified. Integration within an economic modelling framework explicitly highlighted the trade-off between cost-effectiveness, feasibility and equity. This study exemplifies the MRC recommendation to integrate qualitative and quantitative methods in developing complex interventions. The next step in the development pathway should encompass the views of service users.

Objectives: To investigate how interventional procedures (IPs) are introduced into the British National Health Services and identify areas for improvement in the current process., Methods: Qualitative study using one to one semi-structured interviews. Using the framework approach, the data generated from 14 participants were analysed with coding of emergent themes. Data were analysed separately for providers and commissioner organisations., Results: Variations were observed in how IPs are introduced from both the provider and commissioner perspectives. Patterns of approaches allowed the development of models reflecting practice at each type of organisation: very structured in some places to, unstructured or almost non-existent in others. Factors affecting the decision to introduce a procedure include: immediate costs and benefits, numbers of people affected, training requirements, NICE guidance, nature of procedure, support from colleagues, incentives, public or policy-maker pressure, and aims of the institution. Monitoring was seen as a key area for improvement by many., Conclusions: These variations indicate that the process of introducing new IPs in the NHS can be improved. Factors affecting decision-making and problems have been identified. The results of our study could inform and help shape future processes of managing and the introduction of new procedures into the NHS., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To assess the comparative accuracy of potential screening tests for open angle glaucoma (OAG)., Methods: Medline, Embase, Biosis (to November 2005), Science Citation Index (to December 2005), and The Cochrane Library (Issue 4, 2005) were searched. Studies assessing candidate screening tests for detecting OAG in persons older than 40 years that reported true and false positives and negatives were included. Meta-analysis was undertaken using the hierarchical summary receiver operating characteristic model., Results: Forty studies enrolling over 48,000 people reported nine tests. Most tests were reported by only a few studies. Frequency-doubling technology (FDT; C-20-1) was significantly more sensitive than ophthalmoscopy (30, 95% credible interval [CrI] 0-62) and Goldmann applanation tonometry (GAT; 45, 95% CrI 17-68), whereas threshold standard automated perimetry (SAP) and Heidelberg Retinal Tomograph (HRT II) were both more sensitive than GAT (41, 95% CrI 14-64 and 39, 95% CrI 3-64, respectively). GAT was more specific than both FDT C-20-5 (19, 95% CrI 0-53) and threshold SAP (14, 95% CrI 1-37). Judging performance by diagnostic odds ratio, FDT, oculokinetic perimetry, and HRT II are promising tests. Ophthalmoscopy, SAP, retinal photography, and GAT had relatively poor performance as single tests. These findings are based on heterogeneous data of limited quality and as such are associated with considerable uncertainty., Conclusions: No test or group of tests was clearly superior for glaucoma screening. Further research is needed to evaluate the comparative accuracy of the most promising tests.

Purpose: To evaluate the relative benefits and to identify any adverse effects of surgical interventions for limbal stem cell deficiency (LSCD)., Design: Systematic literature review., Methods: We searched the following electronic databases from January 1, 1989 through September 30, 2006: MEDLINE, EMBASE, Science citation index, BIOSIS, and the Cochrane Library. In addition, reference lists were scanned to identify any additional reports. The quality of published reports was assessed using standard methods. The main outcome measure was improvement in vision of at least two Snellen lines of best-corrected visual acuity (BCVA). Data on adverse outcomes also were collected., Results: Twenty-six studies met the inclusion criteria. There were no randomized controlled studies. All 26 studies were either prospective or retrospective case series. For bilateral severe LSCD, keratolimbal allograft was the most common intervention with systemic immunosuppression. Other interventions included eccentric penetrating keratolimbal allografts and cultivated autologous oral mucosal epithelial grafts. An improvement in BCVA of two lines or more was reported in 31% to 67% of eyes. For unilateral severe LSCD, the most common surgical intervention was contralateral conjunctival limbal autograft, with 35% to 88% of eyes gaining an improvement in BCVA of two lines or more. The only study evaluating partial LSCD showed an improvement in BCVA of two lines or more in 39% of eyes., Conclusions: Studies to date have not provided strong evidence to guide clinical practice on which surgery is most beneficial to treat various types of LSCD. Standardized data collection in a multicenter LSCD register is suggested.

Purpose: To systematically review current evidence on the cost-effectiveness of screening strategies for open angle glaucoma (OAG)., Materials and Methods: Studies that reported both costs and outcomes of alternative screening strategies for OAG were identified by a highly sensitive search of electronic databases (eg, MEDLINE, EMBASE, NHS EED, HTA Database), last search December 2005. Data on costs regarding cases and years of visual impairment prevented, cases of blindness prevented, and cases of OAG detected were extracted. Incremental cost-effectiveness ratios were calculated using data provided in the included studies., Results: Four studies met the inclusion criteria. The latest of these was published in 1997. The screening tests and treatments reported in these studies are now not considered to be best practice. Furthermore, data were not reported in sufficient detail to reinterpret the results of the studies in terms of a common outcome measure. Finally, these studies suffered from methodologic weaknesses that further limit their usefulness for decision making., Conclusions: Currently, there is insufficient economic evidence on which to base recommendations regarding screening for OAG. New technologies, potentially suitable as screening devices, and new treatments are available. Further research, both in terms of economic models and conduct of clinical trials with concurrent economic evaluation, may help inform policy makers regarding cost-effectiveness and acceptability of screening for OAG.