Search

Rationale and Aims: Lung health of people with cystic fibrosis (PwCF) can be preserved by daily use of inhaled therapy. Adherence to inhaled therapy, therefore, provides an important process measure to understand the success of care and can be used as a quality indicator. Defining adherence is problematic, however, since the number of prescribed treatments varies considerably between PwCF. The problem is less pronounced among those with Pseudomonas aeruginosa (PA), for whom at least three daily doses of nebulized therapy should be prescribed and who thus constitute a more homogeneous group. The UK CF Registry provides routine data on PA status, but data are only available 12 months after collection. In this study, we aim to prospectively identify contemporary PA status from historic registry data., Method: UK CF Registry data from 2011 to 2015 for PwCF aged ≥16 was used to determine a pragmatic prediction rule for identifying contemporary PA status using historic registry data. Accuracy of three different prediction rules was assessed using the positive predictive value (PPV). The number and proportion of adults predicted to have PA infection were determined overall and per center for the selected prediction rule. Known characteristics linked to PA status were explored to ensure the robustness of the prediction rule., Results: Having CF Registry defined chronic PA status in the two previous years is the selected definition to predict a patient will have PA infection within the current year (population-level PPV = 96%-97%, centre level PPV = 85%-100%). This approach provides a subset of data between 1852 and 1872 patients overall and a range of 8 to 279 patients per center., Conclusion: Historic registry data can be used to contemporaneously identify a subgroup of patients with chronic PA. Since this patient group has a narrower treatment schedule, this can facilitate a better benchmarking of adherence across centers., Competing Interests: The authors declare that they have no conflicts of interest., (© 2021 The Authors. Health Science Reports published by Wiley Periodicals LLC.)

Rationale, Aims, and Objective: We previously demonstrated that annual review %FEV 1 underestimates lung health of adults with CF compared with %FEV 1 captured during periods of clinical stability. This has implications in the comparisons against registries with encounter-based FEV 1 , such as the United States. It is uncertain whether this bias affects between-centre comparison within the United Kingdom. Previous funnel plot analyses have identified variation in annual review %FEV 1 according to centre size; hence, we investigated whether paired differences between annual review and best %FEV 1 also vary according to centre size., Methods: This registry analysis included 18 adult CF centres in the United Kingdom with ≥80% completeness for best FEV 1 data in 2014. Mean discrepancy between annual review and best %FEV 1 is a surrogate for the extent by which annual review %FEV 1 underestimates lung health, and was plotted against centre size. A local polynomial regression (LOESS) curve was used to explore the relationship between the two variables. An appropriate model is fitted based on the LOESS curve to determine the strength of relationship between discrepancies in %FEV 1 and centre size., Results: There is an inverted U-shaped relationship between mean discrepancies in %FEV 1 and centre size. A regression of the paired mean difference in %FEV 1 against centre size showed a significant improvement in the goodness of fit for a quadratic model (R 2  = 23.8% for a quadratic model compared with 0.4% for a linear one; P = 0.048 for the quadratic term)., Conclusions: Annual review %FEV 1 underestimated lung health of adults from small and large centres in the United Kingdom to a greater extent compared with medium-sized centres. A plot of %FEV 1 against centre size (eg, funnel plot comparison) would be affected by systematic bias in annual review %FEV 1 . Therefore, annual review %FEV 1 is an unreliable metric to compare health outcomes of adult CF centres within the United Kingdom., (© 2019 John Wiley & Sons, Ltd.)

Rationale, Aims and Objective: Cross-country comparisons of cystic fibrosis (CF) outcomes can potentially identify variation in care but are dependent on data quality. An important assumption is that the UK annual review FEV 1 is only collected during periods of clinical stability. If this assumption does not hold, results of FEV 1 comparisons may be biased in favour of registries with encounter-based FEV 1 . We aimed to test the assumption that CF annual reviews in the UK are only performed during periods of clinical stability., Method: Prospective encounter-based data collected in Sheffield (n = 174) was used to establish whether annual review FEV 1 were always collected during periods of clinical stability and to determine the group-level discrepancy between annual review vs best FEV 1 . We then went on to quantify the group-level discrepancy between annual review and best annual FEV 1 readings within the UK registry (n = 2995) to determine if the differences observed in Sheffield also apply to the wider UK data., Results: Sheffield results showed a group-level discrepancy between best and annual review FEV 1 of -2.5% (95% CI -3.95% to -1.2%) for annual reviews performed during periods of clinical stability (n = 50). The group-level discrepancy is larger at -8.0% (95% CI -11.2% to -4.9%) among annual reviews performed during periods of clinical instability (n = 13). Therefore, the magnitude of this group-level discrepancy is a surrogate for the proportion of clinically stable annual reviews-smaller discrepancy indicates a higher proportion of clinically stable annual reviews and vice versa. The overall group-level discrepancy in the UK registry (-5.6%, 95% CI -5.9 to -5.4%) was similar to Sheffield (-6.1%, 95% CI -7.1 to -5.1%). Around 20% of the clinician reviewed, annual reviews in Sheffield were performed during periods of clinically instability., Conclusions: Annual review FEV 1 underestimates lung health of adults with CF in the UK and may bias cross-country comparisons., (© 2018 The Authors Journal of Evaluation in Clinical Practice Published by John Wiley & Sons Ltd.)

Background: Forced expiratory volume in one second (FEV 1 ) is an important cystic fibrosis (CF) prognostic marker and an established endpoint for CF clinical trials. FEV 1 is also used in observation studies, e.g. to compare different centre's outcomes. We wished to evaluate whether different methods of processing FEV 1 data can impact on a centre's outcome. Methods: This is a single-centre retrospective analysis of routinely collected data from 2013-2016 which included 208 adults with CF. Year-to-year %FEV 1 change was calculated by subtracting best %FEV 1 at Year 1 from Year 2 (i.e. negative values indicate %FEV 1 decline), and compared using Friedman test. Three methods were used to process %FEV 1 data. First, %FEV 1 calculated with Knudson equation was extracted directly from spirometer machines. Second, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and Knudson equation. Third, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and GLI equation. In addition, %FEV 1 decline calculated using GLI equation was adjusted for baseline %FEV 1 to understand the impact of case-mix adjustment. Results: There was a trend of reduction in %FEV 1 decline with all three data processing methods but the magnitude of %FEV 1 decline differed. Median change in %FEV 1 for 2013-2014, 2014-2015 and 2015-2016 was -2.0, -1.0 and 0.0 respectively using %FEV 1 in Knudson equation whereas the median change was -1.1, -0.9 and -0.3 respectively using %FEV 1 in the GLI equation. A statistically significant p-value (0.016) was only obtained when using %FEV 1 in Knudson equation extracted directly from spirometer machines. Conclusions: Although the trend of reduction in %FEV 1 decline was robust, different data processing methods yielded varying results when %FEV 1 decline was compared using a standard related group non-parametric statistical test. Observational studies with %FEV 1 decline as an outcome measure should carefully consider and clearly specify the data processing methods used., Competing Interests: No competing interests were disclosed.

Background: Preventative inhaled treatments in cystic fibrosis will only be effective in maintaining lung health if used appropriately. An accurate adherence index should therefore reflect treatment effectiveness, but the standard method of reporting adherence, that is, as a percentage of the agreed regimen between clinicians and people with cystic fibrosis, does not account for the appropriateness of the treatment regimen. We describe two different indices of inhaled therapy adherence for adults with cystic fibrosis which take into account effectiveness, that is, "simple" and "sophisticated" normative adherence., Methods to Calculate Normative Adherence: Denominator adjustment involves fixing a minimum appropriate value based on the recommended therapy given a person's characteristics. For simple normative adherence, the denominator is determined by the person's Pseudomonas status. For sophisticated normative adherence, the denominator is determined by the person's Pseudomonas status and history of pulmonary exacerbations over the previous year. Numerator adjustment involves capping the daily maximum inhaled therapy use at 100% so that medication overuse does not artificially inflate the adherence level., Three Illustrative Cases: Case A is an example of inhaled therapy under prescription based on Pseudomonas status resulting in lower simple normative adherence compared to unadjusted adherence. Case B is an example of inhaled therapy under-prescription based on previous exacerbation history resulting in lower sophisticated normative adherence compared to unadjusted adherence and simple normative adherence. Case C is an example of nebulizer overuse exaggerating the magnitude of unadjusted adherence., Conclusion: Different methods of reporting adherence can result in different magnitudes of adherence. We have proposed two methods of standardizing the calculation of adherence which should better reflect treatment effectiveness. The value of these indices can be tested empirically in clinical trials in which there is careful definition of treatment regimens related to key patient characteristics, alongside accurate measurement of health outcomes.

Background: Cystic fibrosis (CF) health care professionals recognize the need to motivate people with CF to adhere to nebulizer treatments, yet little is known about how best to achieve this. We aimed to produce motivational posters to support nebulizer adherence by using social marketing involving people with CF in the development of those posters., Methods: The Sheffield CF multidisciplinary team produced preliminary ideas that were elaborated upon with semi-structured interviews among people with CF to explore barriers and facilitators to the use of nebulized therapy. Initial themes and poster designs were refined using an online focus group to finalize the poster designs., Results: People with CF preferred aspirational posters describing what could be achieved through adherence in contrast to posters that highlighted the adverse consequences of nonadherence. A total of 14 posters were produced through this process., Conclusion: People with CF can be engaged to develop promotional material to support adherence, providing a unique perspective differing from that of the CF multidisciplinary team. Further research is needed to evaluate the effectiveness of these posters to support nebulizer adherence.