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Purpose: This study tested the hypothesis that ecological momentary assessment (EMA) of pelvic pain (PP) and urinary urgency (UU) would reveal unique Urologic Chronic Pelvic Pain Syndrome (UCPPS) phenotypes that would be associated with disease specific quality of life (QOL) and illness impact metrics (IIM)., Materials and Methods: A previously validated smart phone app (M-app) was provided to willing Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) participants. M-app notifications were sent 4-times daily for 14 days inquiring about PP and UU severity. A clustering algorithm that accounted for variance placed participants into PP and UU variability? clusters. Associations between clusters and QOL and IIM were then determined., Results: A total of 204 participants enrolled in the M-app study (64% female). M-app compliance was high (median 63% of surveys). Cluster analysis revealed k = 3 (high, low, none) PP clusters and k = 2 (high, low) UU clusters. When adjusting for baseline pain severity, high PP variability, but not UU variability, was strongly associated with QOL and IIM; specifically worse mood, worse sleep and higher anxiety. UU and PP clusters were associated with each other (p < 0.0001), but a large percentage (33%) of patients with high PP variability had low UU variability., Conclusions: PP variability is an independent predictor of worse QOL and more severe IIM in UCPPS participants after controlling for baseline pain severity and UU. These findings suggest alternative pain indices, such as pain variability and unpredictability, may be useful adjuncts to traditional measures of worst and average pain when assessing UCPPS treatment responses., (© 2024 The Authors. Neurourology and Urodynamics published by Wiley Periodicals LLC.)

Purpose: In patients with urologic chronic pelvic pain syndrome (UCPPS), the presence of widespread pain appears to identify a distinct phenotype, with a different symptom trajectory and potentially different response to treatment than patients with pelvic pain only., Materials and Methods: A 76-site body map was administered four times, at weekly intervals, to 568 male and female UCPPS participants in the MAPP Network protocol. The 76 sites were classified into 13 regions (1 pelvic region and 12 nonpelvic regions). The degree of widespread pain was scored from 0 to 12 based on the number of reported nonpelvic pain regions. This continuous body map score was regressed over other measures of widespread pain, with UCPPS symptom severity, and with psychosocial variables to measure level of association. These models were repeated using an updated body map score (0-12) that incorporated a threshold of pain ≥ 4 at each site., Results: Body map scores showed limited variability over the 4 weekly assessments, indicating that a single baseline assessment was sufficient. The widespread pain score correlated highly with other measures of widespread pain and correlated with worsened UCPPS symptom severity and psychosocial functioning. Incorporating a pain severity threshold ≥4 resulted in only marginal increases in these correlations., Conclusions: These results support the use of this 13-region body map in the baseline clinical assessment of UCPPS patients. It provides reliable data about the presence of widespread pain and does not require measurement of pain severity, making it relatively simple to use for clinical purposes., (© 2024 The Authors. Neurourology and Urodynamics published by Wiley Periodicals LLC.)

Introduction and Hypothesis: Although allusions to the importance of a good physician-patient relationship are present throughout the interstitial cystitis/bladder pain syndrome (IC/BPS) literature, qualitative analysis of patients' perspectives on the clinical encounter is lacking, particularly among women who are most commonly affected by IC/BPS. Therefore, we adopted a patient-centered experiential approach to understanding female patients' perception of clinical encounters., Methods: We re-analyzed previously collected data from a qualitative study on patient flare experiences including eight focus groups of female IC/BPS patients (n = 57, mean = 7/group). Qualitative analysis applied grounded theory to index all physician-patient interactions, then thematically coded these interactions to elucidate common experiences of clinical encounters., Results: Women with IC/BPS shared common experiences of provider disbelief and pain dismissal. Discussions with participants demonstrated the extent to which these negative encounters shape patients' health care-seeking behavior, outlook, and psychosocial well-being. Appearing in more than one guise, provider disbelief and dismissal occurred as tacit insinuations, explicit statements, silence, oversimplification, and an unwillingness to listen and discuss alternative treatment. As a result, women adopted several strategies including: rotating specialists; "testing" physicians; self-advocacy; self-management; avoiding the stigma of chronic pain; crying; and opting for alternative medicine over biomedicine., Conclusions: The prevalence of provider disbelief and pain dismissal among women with IC/BPS indicates a need to improve physician-patient communication, informed by the struggles, anxieties, and gendered inequities that female patients with chronic pain experience in their diagnostic journey. Results suggest that further investigation into the power dynamics of clinical encounters might be required., (© 2023. The International Urogynecological Association.)

Purpose: Symptom heterogeneity in interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome, collectively termed urological chronic pelvic pain syndrome, has resulted in difficulty in defining appropriate clinical trial endpoints. We determine clinically important differences for 2 primary symptom measures, pelvic pain severity and urinary symptom severity, and evaluate subgroup differences., Materials and Methods: The Multidisciplinary Approach to the Study of Chronic Pelvic Pain Symptom Patterns Study enrolled individuals with urological chronic pelvic pain syndrome. We defined clinically important differences by associating changes in pelvic pain severity and urinary symptom severity over 3 to 6 months with marked improvement on a global response assessment using regression and receiver operating characteristic curves. We evaluated clinically important differences for absolute and percent change and examined differences in clinically important differences by sex-diagnosis, presence of Hunner lesions, pain type, pain widespreadness, and baseline symptom severity., Results: An absolute change of -4 was clinically important in pelvic pain severity among all patients, but clinically important difference estimates differed by pain type, presence of Hunner lesions, and baseline severity. Pelvic pain severity clinically important difference estimates for percent change were more consistent across subgroups and ranged from 30% to 57%. The absolute change urinary symptom severity clinically important difference was -3 for female participants and -2 for male participants with chronic prostatitis/chronic pelvic pain syndrome only. Patients with greater baseline severity required larger decreases in symptoms to feel improved. Estimated clinically important differences had lower accuracy among participants with low baseline symptoms., Conclusions: A reduction of 30%-50% in pelvic pain severity is a clinically meaningful endpoint for future therapeutic trials in urological chronic pelvic pain syndrome. Urinary symptom severity clinically important differences are more appropriately defined separately for male and female participants.

Variability in pain-related outcomes can hamper assay sensitivity of chronic pain clinical trials. Expectations of outcome in such trials may account for some of this variability, and thereby impede development of novel pain treatments. Measurement of participants' expectations prior to initiating study treatment (active or placebo) is infrequent, variable, and often unvalidated. Efforts to optimize and standardize measurement, analysis, and management of expectations are needed. In this Focus Article, we provide an overview of research findings on the relationship between baseline expectations and pain-related outcomes in clinical trials of pharmacological and nonpharmacological pain treatments. We highlight the potential benefit of adjusting for participants' expectations in clinical trial analyses and draw on findings from patient interviews to discuss critical issues related to measurement of expectations. We conclude with suggestions regarding future studies focused on better understanding the utility of incorporating these measures into clinical trial analyses. PERSPECTIVE: This focus article provides an overview of the relationship between participants' baseline expectations and pain-related outcomes in the setting of clinical trials of chronic pain treatments. Systematic research focused on the measurement of expectations and the impact of adjusting for expectations in clinical trial analyses may improve assay sensitivity., (Copyright © 2023 United States Association for the Study of Pain, Inc. Published by Elsevier Inc. All rights reserved.)

Objectives: To identify patient risk factors associated with prescription opioid misuse and abuse as well as groupings of misuse and abuse behaviors as measured by the Prescription Opioid Misuse and Abuse Questionnaire (POMAQ)., Methods: Adults with chronic pain requiring long-term treatment with opioids completed the POMAQ and other study questionnaires. Latent class analysis (LCA) was used to examine underlying subgroups exhibiting particular risk profiles. Patient demographic and clinical characteristics were examined as covariates and the concordance between the identified latent classes at-risk classifications and the POMAQ clinical scoring algorithm was assessed., Results: Analysis of data from 809 patients revealed four classes: "chronic pain, low risk" ( n  = 473, low to no prevalence of POMAQ behaviors), "chronic pain, comorbid condition" ( n  = 152, high prevalence of anti-anxiety, sleeping pill, and antihistamine use), "at risk" ( n  = 154, taking more opioids than prescribed and drinking alcohol with opioids more frequently than other groups), and "high risk" ( n  = 30, highest prevalence of each behavior). The "high risk" group was associated with being younger, less educated, and unemployed compared to other groups. When examining the LCA classes by groups defined by the original POMAQ clinical scoring algorithm, the "high risk" class had the highest proportion of participants identified with abuse behaviors (46.7%), compared to just 4.7% in the "chronic pain, low risk" group., Conclusions: Findings suggest there are four distinct subgroups of patients defined by chronic opioid misuse and abuse behaviors and support the use of the POMAQ to identify risk factors associated with prescription opioid misuse and abuse.

Abstract: Chronic pain clinical trials have historically assessed benefit and risk outcomes separately. However, a growing body of research suggests that a composite metric that accounts for benefit and risk in relation to each other can provide valuable insights into the effects of different treatments. Researchers and regulators have developed a variety of benefit-risk composite metrics, although the extent to which these methods apply to randomized clinical trials (RCTs) of chronic pain has not been evaluated in the published literature. This article was motivated by an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials consensus meeting and is based on the expert opinion of those who attended. In addition, a review of the benefit-risk assessment tools used in published chronic pain RCTs or highlighted by key professional organizations (ie, Cochrane, European Medicines Agency, Outcome Measures in Rheumatology, and U.S. Food and Drug Administration) was completed. Overall, the review found that benefit-risk metrics are not commonly used in RCTs of chronic pain despite the availability of published methods. A primary recommendation is that composite metrics of benefit-risk should be combined at the level of the individual patient, when possible, in addition to the benefit-risk assessment at the treatment group level. Both levels of analysis (individual and group) can provide valuable insights into the relationship between benefits and risks associated with specific treatments across different patient subpopulations. The systematic assessment of benefit-risk in clinical trials has the potential to enhance the clinical meaningfulness of RCT results., (Copyright © 2021 International Association for the Study of Pain.)

Abstract: Opioids relieve acute pain, but there is little evidence to support the stability of the benefit over long-term treatment of chronic noncancer pain. Previous systematic reviews consider only group level published data which did not provide adequate detail. Our goal was to use patient-level data to explore the stability of pain, opioid dose, and either physical function or pain interference in patients treated for 12 months with abuse deterrent formulations of oxycodone and hydrocodone. All available studies in the Food and Drug Administration Document Archiving, Reporting, and Regulatory Tracking System were included. Patient-level demographics, baseline data, exposure, and outcomes were harmonized. Individual patient slopes were calculated from a linear model of pain, physical function, and pain interference to determine response over time. Opioid dose was summarized by change between baseline and the final month of observation. Patients with stable or less pain, stable or lower opioid dose, and stable or better physical function (where available) met our prespecified criteria for maintaining long-term benefit from chronic opioids. Of the complete data set of 3192 patients, 1422 (44.5%) maintained their pain level and opioid dose. In a secondary analysis of 985 patients with a measured physical function, 338 (34.3%) maintained their physical function in addition to pain and opioid dose. Of 2040 patients with pain interference measured, 788 (38.6%) met criteria in addition. In a carefully controlled environment, about one-third of patients successfully titrated on opioids to treat chronic noncancer pain demonstrated continued benefit for up to 12 months., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the International Association for the Study of Pain.)

Abstract: Randomized clinical trials have demonstrated the efficacy of opioid analgesics for the treatment of acute and chronic pain conditions, and for some patients, these medications may be the only effective treatment available. Unfortunately, opioid analgesics are also associated with major risks (eg, opioid use disorder) and adverse outcomes (eg, respiratory depression and falls). The risks and adverse outcomes associated with opioid analgesics have prompted efforts to reduce their use in the treatment of both acute and chronic pain. This article presents Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) consensus recommendations for the design of opioid-sparing clinical trials. The recommendations presented in this article are based on the following definition of an opioid-sparing intervention: any intervention that (1) prevents the initiation of treatment with opioid analgesics, (2) decreases the duration of such treatment, (3) reduces the total dosages of opioids that are prescribed for or used by patients, or (4) reduces opioid-related adverse outcomes (without increasing opioid dosages), all without causing an unacceptable increase in pain. These recommendations are based on the results of a background review, presentations and discussions at an IMMPACT consensus meeting, and iterative drafts of this article modified to accommodate input from the co-authors. We discuss opioid sparing definitions, study objectives, outcome measures, the assessment of opioid-related adverse events, incorporation of adequate pain control in trial design, interpretation of research findings, and future research priorities to inform opioid-sparing trial methods. The considerations and recommendations presented in this article are meant to help guide the design, conduct, analysis, and interpretation of future trials., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the International Association for the Study of Pain.)

Objective: A chronic pain patient sample living in the United States who participated in a cross-sectional study to evaluate the validity and reproducibility of the Prescription Opioid Misuse and Abuse Questionnaire is characterized., Methods: Patients with chronic pain identified through electronic medical records as refilling at least one opioid prescription within the prior 3 months were recruited from five United States Department of Defense Military Health System clinics. Patients completed the Prescription Opioid Misuse and Abuse Questionnaire, Brief Pain Inventory-Short Form, Medical Outcomes Study: 36-item Short Form, and sociodemographic questions online. Clinical characteristics and electronic medical records for 1 year prior to consent were collected., Results: 809 (86.2%) participants completed the Prescription Opioid Misuse and Abuse Questionnaire. Mean (± standard deviation) age was 55.4 ± 12.7 years; the majority female (55.5%) and white (74.8%). Mean duration of chronic pain was 14.7 ± 10.5 years; the most common pain conditions were lower back pain (76.6%), neck or shoulder pain (60.3%), and osteoarthritis (38.7%). The most commonly prescribed opioids were oxycodone (35.7%), tramadol (34.5%), and hydrocodone (26.9%); 54.8% took one opioid, 44.9% took 2 or more opioids., Discussion: Participants' health status was poor; pain severity and interference were moderate. Electronic medical record data revealed high healthcare resource utilization. This chronic pain population was severely impacted by their pain condition(s).

Objective: The Prescription Opioid Misuse and Abuse Questionnaire was developed to identify prescription opioid abuse and misuse among patients with chronic pain, however, evidence of construct validity and reproducibility is needed., Methods: Chronic pain patients were recruited from five Department of Defense Military Health System clinics across the United States. Construct validity was examined using subjective clinician-reported and patient-reported measures as well as objective information (e.g. hair/urine drug screens and electronic medical records). Test-retest reliability was assessed across 2 timepoints among a subgroup of patients with stable chronic pain., Results: Of 3,263 screened patients, 938 (28.7%) met eligibility and were enrolled; 809 (86.2%) completed the Prescription Opioid Misuse and Abuse Questionnaire. Construct validity was supported by comparison to other validated questionnaires and hair and urine screens which yielded high agreements with patient reports on the Prescription Opioid Misuse and Abuse Questionnaire. Electronic medical record data supported patients' Prescription Opioid Misuse and Abuse Questionnaire responses regarding physician and emergency room visits and opioid refills. The Prescription Opioid Misuse and Abuse Questionnaire had excellent test-retest reliability; the percentage agreement between the two Prescription Opioid Misuse and Abuse Questionnaire administrations was high (>90%) for most questions., Discussion: Results suggest that the Prescription Opioid Misuse and Abuse Questionnaire is a valid and reproducible tool that can be used to assess the presence of prescription opioid misuse and abuse among patients with chronic pain.

Interpreting randomized clinical trials (RCTs) is crucial to making decisions regarding the use of analgesic treatments in clinical practice. In this article, we report on an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) consensus meeting organized by the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks, the purpose of which was to recommend approaches that facilitate interpretation of analgesic RCTs. We review issues to consider when drawing conclusions from RCTs, as well as common methods for reporting RCT results and the limitations of each method. These issues include the type of trial, study design, statistical analysis methods, magnitude of the estimated beneficial and harmful effects and associated precision, availability of alternative treatments and their benefit-risk profile, clinical importance of the change from baseline both within and between groups, presentation of the outcome data, and the limitations of the approaches used.

The estimated probability of progressing from phase 3 analgesic clinical trials to regulatory approval is approximately 57%, suggesting that a considerable number of treatments with phase 2 trial results deemed sufficiently successful to progress to phase 3 do not yield positive phase 3 results. Deficiencies in the quality of clinical trial conduct could account for some of this failure. An Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials meeting was convened to identify potential areas for improvement in trial conduct in order to improve assay sensitivity (ie, ability of trials to detect a true treatment effect). We present recommendations based on presentations and discussions at the meeting, literature reviews, and iterative revisions of this article. The recommendations relate to the following areas: 1) study design (ie, to promote feasibility), 2) site selection and staff training, 3) participant selection and training, 4) treatment adherence, 5) data collection, and 6) data and study monitoring. Implementation of these recommendations may improve the quality of clinical trial data and thus the validity and assay sensitivity of clinical trials. Future research regarding the effects of these strategies will help identify the most efficient use of resources for conducting high quality clinical trials. PERSPECTIVE: Every effort should be made to optimize the quality of clinical trial data. This manuscript discusses considerations to improve conduct of pain clinical trials based on research in multiple medical fields and the expert consensus of pain researchers and stakeholders from academia, regulatory agencies, and industry., (Copyright © 2020. Published by Elsevier Inc.)

Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals with other chronic overlapping pain conditions, including fibromyalgia, chronic fatigue, and irritable bowel syndromes. Data from 6 participating MAPP testing sites were pooled for analysis. Participants with UCPPS (n = 153) exhibited an intermediate pain sensitivity phenotype: they were less sensitive relative to the mixed pain group (n = 35) but significantly more sensitive than healthy controls (n = 100). Increased pain sensitivity in patients with UCPPS was associated with both higher levels of clinical pain severity and more painful body areas outside the pelvic region. Exploratory analyses in participants with UCPPS revealed that pain sensitivity increased during periods of urologic symptom flare and that less pressure pain sensitivity at baseline was associated with a greater likelihood of subsequent genitourinary pain improvement 1 year later. The finding that individuals with UCPPS demonstrate nonpelvic pain hypersensitivity that is related to clinical symptoms suggests that central nervous system mechanisms of pain amplification contribute to UCPPS.

Purpose: Breast cancer treatments may lead to chronic pain. For some breast cancer survivors (BCS), this experience can develop into the perception of living with chronic pain. The majority of BCS are postmenopausal and have hormone receptor-positive (HR+) breast cancer requiring aromatase inhibitors (AIs). Neither the prevalence nor risk factors associated with the perception of living with chronic pain among this population are well defined., Methods: We conducted a cross-sectional survey among postmenopausal, HR+ BCS who previously took or were currently taking AIs. The primary outcome was patients' perception of living with chronic pain over the past 6 months. We measured pain and demographic and clinical variables. Multivariable logistic regression analysis was performed to evaluate risk factors associated with the perception of chronic pain., Results: Among 1280 participants, 167 (13%) reported having the perception of living with chronic pain before their breast cancer diagnosis; 426 (34%) reported this perception after completion of non-hormonal cancer treatment. Seventy-eight percent of BCSs reported experiencing at least one type of treatment-related pain within the past 7 days, with 23% experiencing at least three types. The most common types of pain were AI-induced musculoskeletal pain (49%) and pain at the surgery or radiation site (31%). Younger age (< 56), BMI > 25, and the perception of living with chronic pain before diagnosis were risk factors associated with the perception of living with chronic pain., Conclusions: One in three postmenopausal, HR+ BCS considered themselves to be living with chronic pain. Effective interventions to reduce chronic pain are needed.

Purpose: We characterized the location and spatial distribution of whole body pain in patients with urological chronic pelvic pain syndrome using a body map. We also compared the severity of urinary symptoms, pelvic pain, nonpelvic pain and psychosocial health among patients with different pain patterns., Materials and Methods: A total of 233 women and 191 men with urological chronic pelvic pain syndrome enrolled in a multicenter, 1-year observational study completed a battery of baseline measures, including a body map describing the location of pain during the last week. Participants were categorized with pelvic pain if they reported pain in the abdomen and pelvis only. Participants who reported pain beyond the pelvis were further divided into 2 subgroups based on the number of broader body regions affected by pain, including an intermediate group with 1 or 2 additional regions outside the pelvis and a widespread pain group with 3 to 7 additional regions., Results: Of the 424 enrolled patients 25% reported pelvic pain only and 75% reported pain beyond the pelvis, of whom 38% reported widespread pain. Participants with a greater number of pain locations had greater nonpelvic pain severity (p <0.0001), sleep disturbance (p = 0.035), depression (p = 0.005), anxiety (p = 0.011), psychological stress (p = 0.005) and negative affect scores (p = 0.0004), and worse quality of life (p ≤0.021). No difference in pelvic pain and urinary symptom severity was observed according to increasing pain distribution., Conclusions: Three-quarters of the men and women with urological chronic pelvic pain syndrome reported pain outside the pelvis. Widespread pain was associated with greater severity of nonpelvic pain symptoms, poorer psychosocial health and worse quality of life but not with worse pelvic pain or urinary symptoms., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Valid and reliable biomarkers can play an important role in clinical trials as indicators of biological or pathogenic processes or as a signal of treatment response. Currently, there are no biomarkers for pain qualified by the U.S. Food and Drug Administration or the European Medicines Agency for use in clinical trials. This article summarizes an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials meeting in which 3 potential biomarkers were discussed for use in the development of analgesic treatments: 1) sensory testing, 2) skin punch biopsy, and 3) brain imaging. The empirical evidence supporting the use of these tests is described within the context of the 4 categories of biomarkers: 1) diagnostic, 2) prognostic, 3) predictive, and 4) pharmacodynamic. Although sensory testing, skin punch biopsy, and brain imaging are promising tools for pain in clinical trials, additional evidence is needed to further support and standardize these tests for use as biomarkers in pain clinical trials., Perspective: The applicability of sensory testing, skin biopsy, and brain imaging as diagnostic, prognostic, predictive, and pharmacodynamic biomarkers for use in analgesic treatment trials is considered. Evidence in support of their use and outlining problems is presented, as well as a call for further standardization and demonstrations of validity and reliability., (Copyright © 2017 American Pain Society. All rights reserved.)

Although pain reduction is commonly the primary outcome in chronic pain clinical trials, physical functioning is also important. A challenge in designing chronic pain trials to determine efficacy and effectiveness of therapies is obtaining appropriate information about the impact of an intervention on physical function. The Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) and Outcome Measures in Rheumatology (OMERACT) convened a meeting to consider assessment of physical functioning and participation in research on chronic pain. The primary purpose of this article is to synthesize evidence on the scope of physical functioning to inform work on refining physical function outcome measurement. We address issues in assessing this broad construct and provide examples of frequently used measures of relevant concepts. Investigators can assess physical functioning using patient-reported outcome (PRO), performance-based, and objective measures of activity. This article aims to provide support for the use of these measures, covering broad aspects of functioning, including work participation, social participation, and caregiver burden, which researchers should consider when designing chronic pain clinical trials. Investigators should consider the inclusion of both PROs and performance-based measures as they provide different but also important complementary information. The development and use of reliable and valid PROs and performance-based measures of physical functioning may expedite development of treatments, and standardization of these measures has the potential to facilitate comparison across studies. We provide recommendations regarding important domains to stimulate research to develop tools that are more robust, address consistency and standardization, and engage patients early in tool development.

Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (ie, chronic postsurgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (ie, surgery, viral infection, injury, and toxic or noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials.

Objective: Methadone is associated with QT prolongation and serious cardiac complications, but this has been primarily demonstrated in opioid dependent patients receiving moderate to high doses. This study investigates the effect of low-dose methadone on the QTc interval in a chronic pain population., Design and Subjects: We conducted a prospective cohort study in a chronic pain clinic including 82 patients receiving methadone and 102 patients receiving non-methadone opioid therapy., Methods: We analyzed automated QTc calculations from 12-lead electrocardiograms at baseline and during the subsequent 6 months. The primary outcome of interest was the incidence of QTc greater than 470 milliseconds or an increase from baseline of greater than 60 milliseconds., Results: The methadone group did not manifest an overall higher frequency of QTc > 470 milliseconds (6% for the methadone group vs 5% for controls, P = 0.722) or an increase in the QTc of > 60 milliseconds (4% for the methadone group vs 4% for controls, P = 0.94). In the first month after initiating methadone, patients demonstrated an increase in QTc compared to controls (5% for the methadone group vs 0% for the controls, P = 0.073) but the difference disappeared in the third and sixth months., Conclusion: Data from our chronic pain clinic support a potential association of QTc prolongation during the initiation of methadone, but this effect is small and short lived. We believe larger scale studies to further characterize the safety profile of low-dose methadone are warranted., (Wiley Periodicals, Inc.)

Proof-of-concept (POC) clinical trials play an important role in developing novel treatments and determining whether existing treatments may be efficacious in broader populations of patients. The goal of most POC trials is to determine whether a treatment is likely to be efficacious for a given indication and thus whether it is worth investing the financial resources and participant exposure necessary for a confirmatory trial of that intervention. A challenge in designing POC trials is obtaining sufficient information to make this important go/no-go decision in a cost-effective manner. An IMMPACT consensus meeting was convened to discuss design considerations for POC trials in analgesia, with a focus on maximizing power with limited resources and participants. We present general design aspects to consider including patient population, active comparators and placebos, study power, pharmacokinetic-pharmacodynamic relationships, and minimization of missing data. Efficiency of single-dose studies for treatments with rapid onset is discussed. The trade-off between parallel-group and crossover designs with respect to overall sample sizes, trial duration, and applicability is summarized. The advantages and disadvantages of more recent trial designs, including N-of-1 designs, enriched designs, adaptive designs, and sequential parallel comparison designs, are summarized, and recommendations for consideration are provided. More attention to identifying efficient yet powerful designs for POC clinical trials of chronic pain treatments may increase the percentage of truly efficacious pain treatments that are advanced to confirmatory trials while decreasing the percentage of ineffective treatments that continue to be evaluated rather than abandoned., (Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

Objective: This manuscript reviews how patient-reported outcomes data can be used to guide efforts to improve patient outcomes., Design: Review Manuscript., Setting: The clinical management of chronic, non-cancer pain., Subjects: Adult patients receiving treatment for chronic, non-cancer pain., Results: While there have been great advances in the science of pain and various therapeutic medications and interventions, patient outcomes are variable. This manuscript reviews how outcomes data can be used to guide efforts to improve patient outcomes., Conclusions: Patient outcomes can be improved with standardization of the process of patient care, as well as through other quality improvement efforts. The cornerstone to any effort to improve patient outcomes starts with the integration of valid outcomes data collection into ongoing patient care. Outcome measurement tools should provide information on several key domains, yet the process of data collection should not pose a significant burden on either the patient or health care team. Efforts to improve patient outcomes are ongoing, and should be a high priority for every health care team., (Wiley Periodicals, Inc.)

Objective: The purpose of this study was to determine if the opioid risk tool (ORT) was clinically useful in guiding physician decision making during chronic opioid therapy and to determine whether there were differences between the patient-completed and physician-completed ORT., Design: Retrospective review of prospectively collected data., Setting: A single-center tertiary care outpatient pain management center., Patients, Participants: One-hundred twenty-five patients who received chronic opioids as part of their pain therapy., Interventions: Patients receiving care were asked to complete the ORT as part of their initial evaluation. In addition, as part of this study, a pain physician reviewed the information available at the time of the initial evaluation and completed the ORT. Medical records were reviewed for evidence of moderate-to-severe aberrant drug-related behavior (ADRB), according to specified criteria., Main Outcome Measures: Patient-completed and physician-completed ORT and presence or absence of moderate to severe ADRB., Results: Of the 125 patients included in this study, physician-completed ORT was available for 125 patients, and a patient-completed ORT was available on 87 of these patients. There was good correlation between the patient-completed and physician-completed ORT (correlation coefficient = 0.61). There were 112 observations of ADRB in 53 of 125 patients (42.4 percent) during the observation period of an average of 7.8 months (range 2-17 months). Of these 53 patients, 32 (60.4 percent) were identified by urine drug screen (UDS) alone, 7 (13.2 percent) were identified by physician observation alone, and 14 (26.4 percent) were identified by both UDS and physician observation. Based on the physician-completed ORT, 41 of 106 (38.7 percent) low risk patients had ADRB, compared to 8 of 14 (57.1 percent) moderate risk, and 4 of 5 (80 percent) high risk patients., Conclusions: Neither the patient-completed nor the physician-completed ORT was strongly predictive of moderate-to-severe ADRB in patients receiving chronic opioid therapy for the treatment of noncancer pain in our pain center.

Unlabelled: Use of opioid analgesics for pain management has increased dramatically over the past decade, with corresponding increases in negative sequelae including overdose and death. There is currently no well-validated objective means of accurately identifying patients likely to experience good analgesia with low side effects and abuse risk prior to initiating opioid therapy. This paper discusses the concept of data-based personalized prescribing of opioid analgesics as a means to achieve this goal. Strengths, weaknesses, and potential synergism of traditional randomized placebo-controlled trial (RCT) and practice-based evidence (PBE) methodologies as means to acquire the clinical data necessary to develop validated personalized analgesic-prescribing algorithms are overviewed. Several predictive factors that might be incorporated into such algorithms are briefly discussed, including genetic factors, differences in brain structure and function, differences in neurotransmitter pathways, and patient phenotypic variables such as negative affect, sex, and pain sensitivity. Currently available research is insufficient to inform development of quantitative analgesic-prescribing algorithms. However, responder subtype analyses made practical by the large numbers of chronic pain patients in proposed collaborative PBE pain registries, in conjunction with follow-up validation RCTs, may eventually permit development of clinically useful analgesic-prescribing algorithms., Perspective: Current research is insufficient to base opioid analgesic prescribing on patient characteristics. Collaborative PBE studies in large, diverse pain patient samples in conjunction with follow-up RCTs may permit development of quantitative analgesic-prescribing algorithms that could optimize opioid analgesic effectiveness and mitigate risks of opioid-related abuse and mortality., (Copyright © 2013 American Pain Society. All rights reserved.)

A number of pharmacologic treatments examined in recent randomized clinical trials (RCTs) have failed to show statistically significant superiority to placebo in conditions in which their efficacy had previously been demonstrated. Assuming the validity of previous evidence of efficacy and the comparability of the patients and outcome measures in these studies, such results may be a consequence of limitations in the ability of these RCTs to demonstrate the benefits of efficacious analgesic treatments vs placebo ("assay sensitivity"). Efforts to improve the assay sensitivity of analgesic trials could reduce the rate of falsely negative trials of efficacious medications and improve the efficiency of analgesic drug development. Therefore, an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials consensus meeting was convened in which the assay sensitivity of chronic pain trials was reviewed and discussed. On the basis of this meeting and subsequent discussions, the authors recommend consideration of a number of patient, study design, study site, and outcome measurement factors that have the potential to affect the assay sensitivity of RCTs of chronic pain treatments. Increased attention to and research on methodological aspects of clinical trials and their relationships with assay sensitivity have the potential to provide the foundation for an evidence-based approach to the design of analgesic clinical trials and expedite the identification of analgesic treatments with improved efficacy and safety., (Copyright © 2012 International Association for the Study of Pain. All rights reserved.)

Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals with other chronic overlapping pain conditions, including fibromyalgia, chronic fatigue, and irritable bowel syndromes. Data from 6 participating MAPP testing sites were pooled for analysis. Participants with UCPPS (n = 153) exhibited an intermediate pain sensitivity phenotype: they were less sensitive relative to the mixed pain group (n = 35) but significantly more sensitive than healthy controls (n = 100). Increased pain sensitivity in patients with UCPPS was associated with both higher levels of clinical pain severity and more painful body areas outside the pelvic region. Exploratory analyses in participants with UCPPS revealed that pain sensitivity increased during periods of urologic symptom flare and that less pressure pain sensitivity at baseline was associated with a greater likelihood of subsequent genitourinary pain improvement 1 year later. The finding that individuals with UCPPS demonstrate nonpelvic pain hypersensitivity that is related to clinical symptoms suggests that central nervous system mechanisms of pain amplification contribute to UCPPS.

The lack of effective therapeutic agents specifically tailored for chronic pancreatitis (CP) has hampered clinical care and negatively impacted patients' lives. New mechanistic insights now point to novel therapies, which involve both recently developed and/or repurposed agents. This working group focused on 2 main outcomes for CP: pain and progression of disease. The goal is to frame the essential aspects of trial design including patient-centered outcomes, proposed methods to measure the outcomes of pain and progression, and study design considerations for future trials to facilitate rapid drug development for patients with CP.

Chronic cancer pain is a serious complication of malignancy or its treatment. Currently, no comprehensive, universally accepted cancer pain classification system exists. Clarity in classification of common cancer pain syndromes would improve clinical assessment and management. Moreover, an evidence-based taxonomy would enhance cancer pain research efforts by providing consistent diagnostic criteria, ensuring comparability across clinical trials. As part of a collaborative effort between the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) and the American Pain Society (APS), the ACTTION-APS Pain Taxonomy initiative worked to develop the characteristics of an optimal diagnostic system. After the establishment of these characteristics, a working group consisting of clinicians and clinical and basic scientists with expertise in cancer and cancer-related pain was convened to generate core diagnostic criteria for an illustrative sample of 3 chronic pain syndromes associated with cancer (ie, bone pain and pancreatic cancer pain as models of pain related to a tumor) or its treatment (ie, chemotherapy-induced peripheral neuropathy). A systematic review and synthesis was conducted to provide evidence for the dimensions that comprise this cancer pain taxonomy. Future efforts will subject these diagnostic categories and criteria to systematic empirical evaluation of their feasibility, reliability, and validity and extension to other cancer-related pain syndromes.PerspectiveThe ACTTION-APS chronic cancer pain taxonomy provides an evidence-based classification for 3 prevalent syndromes, namely malignant bone pain, pancreatic cancer pain, and chemotherapy-induced peripheral neuropathy. This taxonomy provides consistent diagnostic criteria, common features, comorbidities, consequences, and putative mechanisms for these potentially serious cancer pain conditions that can be extended and applied with other cancer-related pain syndromes.

ObjectiveOur objective was to identify patient, study, and site factors associated with assay sensitivity in placebo-controlled neuropathic pain trials.MethodsWe examined the associations between study characteristics and standardized effect size (SES) in a database of 200 publicly available randomized clinical trials of pharmacologic treatments for neuropathic pain.ResultsThere was considerable heterogeneity in the SESs among the examined trials. Univariate meta-regression analyses indicated that larger SESs were significantly associated with trials that had 1) greater minimum baseline pain inclusion criteria, 2) greater mean subject age, 3) a larger percentage of Caucasian subjects, and 4) a smaller total number of subjects. In a multiple meta-regression analysis, the associations between SES and minimum baseline pain inclusion criterion and age remained significant.ConclusionsOur analyses have examined potentially modifiable correlates of study SES and shown that a minimum pain inclusion criterion of 40 or above on a 0 to 100 scale is associated with a larger SES. These data provide a foundation for investigating strategies to improve assay sensitivity and thereby decrease the likelihood of falsely negative outcomes in clinical trials of efficacious treatments for neuropathic pain.

A critical component in development of opioid analgesics is assessment of their abuse liability (AL). Standardization of approaches and measures used in assessing AL have the potential to facilitate comparisons across studies, research laboratories, and drugs. The goal of this report is to provide consensus recommendations regarding core outcome measures for assessing the abuse potential of opioid medications in humans in a controlled laboratory setting. Although many of the recommended measures are appropriate for assessing the AL of medications from other drug classes, the focus here is on opioid medications because they present unique risks from both physiological (e.g., respiratory depression, physical dependence) and public health (e.g., individuals in pain) perspectives. A brief historical perspective on AL testing is provided, and those measures that can be considered primary and secondary outcomes and possible additional outcomes in AL assessment are then discussed. These outcome measures include the following: subjective effects (some of which comprise the primary outcome measures, including drug liking; physiological responses; drug self-administration behavior; and cognitive and psychomotor performance. Before presenting recommendations for standardized approaches and measures to be used in AL assessments, the appropriateness of using these measures in clinical trials with patients in pain is discussed.

The Prescription Opioid Misuse and Abuse Questionnaire (POMAQ) was developed to identify prescription opioid misuse and abuse among patients with chronic pain. A clinical scoring algorithm was developed and refined to align with the patient experience. This study utilized data from the POMAQ validation study (3033-4, NCT02660606) conducted on a sample of patients with chronic pain living in the United States. The study was carried out in two phases. Two purposefully enriched patient samples, one for each phase, were created based on patient responses to select POMAQ items and the availability of urine and hair samples. Two clinical experts (SHS, SFB) reviewed patient data to classify prescription opioid use behavior. Classification differences were adjudicated by a third clinical expert (JTF). Comparisons were made between the final clinical classification determined by the experts and the proposed classification based on the POMAQ algorithm. Sixty patients were included in Phase I (only POMAQ data) and 52 in Phase II (including POMAQ and ancillary sources [e.g. electronic medical records, urine toxicity screen]). Refinements were made to the POMAQ scoring algorithm following discussions with clinical experts to ensure it was clinically relevant. For both phases, classifications were reviewed and discussed to achieve maximal concordance of classifications across experts. The proposed scoring algorithm was then modified to maximize agreement with the expert interpretation of clinically relevant patient experiences. The clinical scoring algorithm for the POMAQ was developed and refined to reflect clinically relevant patient behaviors identified by expert review. Future testing is needed to determine the sensitivity and specificity of this measure. [ABSTRACT FROM AUTHOR]

Background: The prevalence of neuropathic pain (NeP) has been estimated within specific health conditions; however, there are no published data on its broad prevalence in the US. The current exploratory study addresses this gap using the validated PainDetect questionnaire as a screener for probable NeP in a general-population health survey conducted with a multimodal recruitment strategy to maximize demographic representativeness. Materials and methods: Adult respondents were recruited from a combination of Internet panels, telephone lists, address lists, mall-based interviews and store-receipt invitations using a random stratified-sampling framework, with strata defined by age, sex and race/ethnicity. Older persons and minorities were oversampled to improve prevalence estimates. Results were weighted to match the total adult US population using US Census data. Demographic information was collected and respondents who experienced physical pain in the past 12 months completed the PainDetect and provided additional pain history. A cutoff score of 19 or greater on the PainDetect was used to define probable NeP. Results: A total of 24,925 respondents (average response rate 2.5%) provided demographic data (52.2% female, mean age 51.5 years); 15,751 respondents reported pain (63.7%), of which 2,548 (15.7%, 95% confidence interval 14.9%-16.5%) had probable NeP based on the PainDetect, which was 10% (95% confidence interval 9.5%-10.5%) of all respondents. Among those reporting pain, the prevalence of probable NeP among Blacks and Hispanics was consistently higher than Whites in each age and sex group. The highest prevalence among those with pain was among male Hispanics 35-44 years (32.4%) and 45-54 years (24.2%) old. The most commonly used medications reported by those with probable NeP were nonsteroidal anti-inflammatory drugs (44.2%), followed by weak opioids (31.7%), antiepileptics (10.9%) and strong opioids (10.9%). Conclusion: This is the first study to provide an estimate of the prevalence of probable NeP in the US, showing significant variation by age and ethnicity. [ABSTRACT FROM AUTHOR]

Abstract: Methadone is used for the treatment of opioid addiction and for treatment of chronic pain. The safety of methadone has been called into question by data indicating a large increase in the number of methadone-associated overdose deaths in recent years that has occurred in parallel with a dramatic rise in the use of methadone for chronic pain. The American Pain Society and the College on Problems of Drug Dependence, in collaboration with the Heart Rhythm Society, commissioned an interdisciplinary expert panel to develop a clinical practice guideline on safer prescribing of methadone for treatment of opioid addiction and chronic pain. As part of the guideline development process, the American Pain Society commissioned a systematic review of various aspects related to safety of methadone. After a review of the available evidence, the expert panel concluded that measures can be taken to promote safer use of methadone. Specific recommendations include the need to educate and counsel patients on methadone safety, use of electrocardiography to identify persons at greater risk for methadone-associated arrhythmia, use of alternative opioids in patients at high risk of complications related to corrected electrocardiographic QTc interval prolongation, careful dose initiation and titration of methadone, and diligent monitoring and follow-up. Although these guidelines are based on a systematic review, the panel identified numerous research gaps, most recommendations were based on low-quality evidence, and no recommendations were based on high-quality evidence. Perspective: This guideline, based on a systematic review of the evidence on methadone safety, provides recommendations developed by a multidisciplinary expert panel. Safe use of methadone requires clinical skills and knowledge in use of methadone to mitigate potential risks, including serious risks related to risk of overdose and cardiac arrhythmias. [Copyright &y& Elsevier]

Abstract: A consensus meeting was convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) to provide recommendations for interpreting clinical importance of treatment outcomes in clinical trials of the efficacy and effectiveness of chronic pain treatments. A group of 40 participants from universities, governmental agencies, a patient self-help organization, and the pharmaceutical industry considered methodologic issues and research results relevant to determining the clinical importance of changes in the specific outcome measures previously recommended by IMMPACT for 4 core chronic pain outcome domains: (1) Pain intensity, assessed by a 0 to 10 numerical rating scale; (2) physical functioning, assessed by the Multidimensional Pain Inventory and Brief Pain Inventory interference scales; (3) emotional functioning, assessed by the Beck Depression Inventory and Profile of Mood States; and (4) participant ratings of overall improvement, assessed by the Patient Global Impression of Change scale. It is recommended that 2 or more different methods be used to evaluate the clinical importance of improvement or worsening for chronic pain clinical trial outcome measures. Provisional benchmarks for identifying clinically important changes in specific outcome measures that can be used for outcome studies of treatments for chronic pain are proposed. Perspective: Systematically collecting and reporting the recommended information needed to evaluate the clinical importance of treatment outcomes of chronic pain clinical trials will allow additional validation of proposed benchmarks and provide more meaningful comparisons of chronic pain treatments. [Copyright &y& Elsevier]

Background . The purpose of this study was to investigate the cerebral blood flow changes associated with the analgesic effect of acupuncture in patients with chronic pain. Methods. Seven patients presenting with a chronic pain syndrome and 5 healthy controls were included. All single-photon emission computed tomography (SPECT) scans were acquired with a uniform protocol. The patient group was injected with the radioisotope hexamethyl propyleneamine oxime (HMPAO) while experiencing their usual level of pain. A baseline scan was acquired approximately 20 minutes after administration of the HMPAO. The patient then underwent acupuncture therapy with needles placed in points specifically selected to relieve pain. When the pain improved, as determined by a 10-digit score for pain assessment, the patient was reinjected with HMPAO and imaged 20 minutes later for the acupuncture scan. The reference group also had a baseline and acupuncture scan, although the acupuncture itself was performed using a standardized set of needle points. Results. The reference group participants were found to have significant increases in the thalamic and prefrontal cortex activity on the acupuncture scan compared to the baseline. The baseline scans of the pain patients showed significant asymmetric uptake in the thalami compared to controls. This asymmetry reversed or normalized after the acupuncture therapy. Significant correlations were observed between the change of activity in the prefrontal cortex and ipsilateral sensorimotor area. Conclusion. The results from these cases show that HMPAO-SPECT is capable of detecting changes in cerebral blood flow associated with pain and that acupuncture analgesia is associated with changes in the activity of the frontal lobes, brain stem, and thalami. [ABSTRACT FROM AUTHOR]

Abstract: There has been an increase in the number of chronic pain clinical trials in which the treatments being evaluated did not differ significantly from placebo in the primary efficacy analyses despite previous research suggesting that efficacy could be expected. These findings could reflect a true lack of efficacy or methodological and other aspects of these trials that compromise the demonstration of efficacy. There is substantial variability among chronic pain clinical trials with respect to important research design considerations, and identifying and addressing any methodological weaknesses would enhance the likelihood of demonstrating the analgesic effects of new interventions. An IMMPACT consensus meeting was therefore convened to identify the critical research design considerations for confirmatory chronic pain trials and to make recommendations for their conduct. We present recommendations for the major components of confirmatory chronic pain clinical trials, including participant selection, trial phases and duration, treatment groups and dosing regimens, and types of trials. Increased attention to and research on the methodological aspects of confirmatory chronic pain clinical trials has the potential to enhance their assay sensitivity and ultimately provide more meaningful evaluations of treatments for chronic pain. [Copyright &y& Elsevier]

Abstract: An essential component of the interpretation of results of randomized clinical trials of treatments for chronic pain involves the determination of their clinical importance or meaningfulness. This involves two distinct processes—interpreting the clinical importance of individual patient improvements and the clinical importance of group differences—which are frequently misunderstood. In this article, we first describe the essential differences between the interpretation of the clinical importance of patient improvements and of group differences. We then discuss the factors to consider when evaluating the clinical importance of group differences, which include the results of responder analyses of the primary outcome measure, the treatment effect size compared to available therapies, analyses of secondary efficacy endpoints, the safety and tolerability of treatment, the rapidity of onset and durability of the treatment benefit, convenience, cost, limitations of existing treatments, and other factors. The clinical importance of individual patient improvements can be determined by assessing what patients themselves consider meaningful improvement using well-described methods. In contrast, the clinical meaningfulness of group differences must be determined by a multi-factorial evaluation of the benefits and risks of the treatment and of other available treatments for the condition in light of the primary goals of therapy. Such determinations must be conducted on a case-by-case basis, and are ideally informed by patients and their significant others, clinicians, researchers, statisticians, and representatives of society at large. [Copyright &y& Elsevier]

Abstract: The increasing complexity of randomized clinical trials and the practice of obtaining a wide variety of measurements from study participants have made the consideration of multiple endpoints a critically important issue in the design, analysis, and interpretation of clinical trials. Failure to consider important outcomes can limit the validity and utility of clinical trials; specifying multiple endpoints for the evaluation of treatment efficacy, however, can increase the rate of false positive conclusions about the efficacy of a treatment. We describe the use of multiple endpoints in the design, analysis, and interpretation of pain clinical trials, and review available strategies and methods for addressing multiplicity. To decrease the probability of a Type I error (i.e., the likelihood of obtaining statistically significant results by chance) in pain clinical trials, the use of gatekeeping procedures and other methods that correct for multiple analyses is recommended when a single primary endpoint does not adequately reflect the overall benefits of treatment. We emphasize the importance of specifying in advance the outcomes and clinical decision rule that will serve as the basis for determining that a treatment is efficacious and the methods that will be used to control the overall Type I error rate. [Copyright &y& Elsevier]

Abstract: This two-phase study was conducted to identify relevant domains of patient-reported outcomes from the perspective of people who experience chronic pain. In Phase 1, focus groups were conducted to generate a pool of patient outcome-related domains and their components. The results of the focus groups identified 19 aspects of their lives that were significantly impacted by the presence of their symptoms and for which improvements were important criteria they would use in evaluating the effectiveness of any treatment. Phase 2 was conducted to examine the importance and relevance of domains identified from a much larger and diverse sample of people with chronic pain. A survey was developed and posted on the American Chronic Pain Association website. Participants were asked to rate the importance of each item or domain identified by the focus groups on a scale of 0 to10 (i.e., 0=“not at all important” and 10=“extremely important”). The survey was completed by 959 individuals. The results indicate that all 19 aspects of daily life derived from the focus groups were considered important with a majority of respondents indicating a score of 8 or greater. In addition to pain reduction, the most important aspects were enjoyment of life, emotional well-being, fatigue, weakness, and sleep-related problems. Chronic pain clearly impacts health-related quality of life. The results of the two phases of the study indicate that people with chronic pain consider functioning and well-being as important areas affected by the presence of symptoms and as appropriate targets of treatment. These multiple outcomes should be considered when evaluating the efficacy and effectiveness of chronic pain treatments. [Copyright &y& Elsevier]

Objective---To develop and psychometrically test an owner self-administered questionnaire designed to assess severity and impact of chronic pain in dogs with osteoarthritis. Sample Population--70 owners of dogs with osteoarthritis and 50 owners of clinically normal dogs. Procedures--Standard methods for the stepwise development and testing of instruments designed to assess subjective states were used. Items were generated through focus groups and an expert panel. Items were tested for readability and ambiguity, and poorly performing items were removed. The reduced set of items was subjected to factor analysis, reliability testing, and validity testing. Results--Severity of pain and interference with function were 2 factors identified and named on the basis of the items contained in them. Cronbach's α was 0.93 and 0.89, respectively, suggesting that the items in each factor could be assessed as a group to compute factor scores (ie, severity score and interference score). The test-retest analysis revealed κ values of 0.75 for the severity score and 0.81 for the interference score. Scores correlated moderately well (r = 0.51 and 0.50, respectively) with the overall quality-of-life (QOL) question, such that as severity and interference scores increased, QOL decreased. Clinically normal dogs had significantly lower severity and interference scores than dogs with osteoarthritis. Conclusions and Clinical Relevance--A psychometrically sound instrument was developed. Responsiveness testing must be conducted to determine whether the questionnaire will be useful in reliably obtaining quantifiable assessments from owners regarding the severity and impact of chronic pain and its treatment on dogs with osteoarthritis. [ABSTRACT FROM AUTHOR]

Objective. To provide recommendations for the core outcome domains that should be considered by investigators conducting clinical trials of the efficacy and effectiveness of treatments for chronic pain. Development of a core set of outcome domains would facilitate comparison and pooling of data, encourage more complete reporting of outcomes, simplify the preparation and review of research proposals and manuscripts, and allow clinicians to make informed decisions regarding the risks and benefits of treatment.Methods. Under the auspices of the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT), 27 specialists from academia, governmental agencies, and the pharmaceutical industry participated in a consensus meeting and identified core outcome domains that should be considered in clinical trials of treatments for chronic pain.Conclusions. There was a consensus that chronic pain clinical trials should assess outcomes representing six core domains: (1) pain, (2) physical functioning, (3) emotional functioning, (4) participant ratings of improvement and satisfaction with treatment, (5) symptoms and adverse events, (6) participant disposition (e.g. adherence to the treatment regimen and reasons for premature withdrawal from the trial). Although consideration should be given to the assessment of each of these domains, there may be exceptions to the general recommendation to include all of these domains in chronic pain trials. When this occurs, the rationale for not including domains should be provided. It is not the intention of these recommendations that assessment of the core domains should be considered a requirement for approval of product applications by regulatory agencies or that a treatment must demonstrate statistically significant effects for all of the relevant core domains to establish evidence of its efficacy. [Copyright &y& Elsevier]