Novel Oral Lichen Planus Symptom Severity Measure for assessing patients' daily symptom experience.

OBJECTIVE: A novel Oral Lichen Planus Symptom Severity Measure was developed as a clinical outcome assessment of the daily symptom experience of patients with oral lichen planus. METHODS: A literature review and expert input were followed by open-ended concept elicitation interviews with 17 adults with oral lichen planus in the United States and Ireland. Item content was generated, and the interviews continued until input saturation was reached. The final electronic version of the measure was cognitively debriefed in 6 US patients and subsequently translated and linguistically validated in Germany and Denmark. RESULTS: Concept elicitation interviews demonstrated content validity and saturation in identifying symptoms and daily activities that generate symptoms in patients with oral lichen planus. The content and electronic daily diary format demonstrated content validity during cognitive debriefing interviews. Linguistic validation of the 7-item Oral Lichen Planus Symptom Severity Measure in Germany and Denmark confirmed the content validity of the German and Danish versions. CONCLUSIONS: Qualitative research methods generated evidence that the 7-item Oral Lichen Planus Symptom Severity Measure version 1.0 is a well-defined assessment tool to characterize the severity, specificity and variations of symptoms in patients with oral lichen planus.

Clinician-Reported Outcome Assessments of Treatment Benefit: Report of the ISPOR Clinical Outcome Assessment Emerging Good Practices Task Force.

A clinician-reported outcome (ClinRO) assessment is a type of clinical outcome assessment (COA). ClinRO assessments, like all COAs (patient-reported, observer-reported, or performance outcome assessments), are used to 1) measure patients' health status and 2) define end points that can be interpreted as treatment benefits of medical interventions on how patients feel, function, or survive in clinical trials. Like other COAs, ClinRO assessments can be influenced by human choices, judgment, or motivation. A ClinRO assessment is conducted and reported by a trained health care professional and requires specialized professional training to evaluate the patient's health status. This is the second of two reports by the ISPOR Clinical Outcomes Assessment-Emerging Good Practices for Outcomes Research Task Force. The first report provided an overview of COAs including definitions important for an understanding of COA measurement practices. This report focuses specifically on issues related to ClinRO assessments. In this report, we define three types of ClinRO assessments (readings, ratings, and clinician global assessments) and describe emerging good measurement practices in their development and evaluation. The good measurement practices include 1) defining the context of use; 2) identifying the concept of interest measured; 3) defining the intended treatment benefit on how patients feel, function, or survive reflected by the ClinRO assessment and evaluating the relationship between that intended treatment benefit and the concept of interest; 4) documenting content validity; 5) evaluating other measurement properties once content validity is established (including intra- and inter-rater reliability); 6) defining study objectives and end point(s) objectives, and defining study end points and placing study end points within the hierarchy of end points; 7) establishing interpretability in trial results; and 8) evaluating operational considerations for the implementation of ClinRO assessments used as end points in clinical trials. Applying good measurement practices to ClinRO assessment development and evaluation will lead to more efficient and accurate measurement of treatment effects. This is important beyond regulatory approval in that it provides evidence for the uptake of new interventions into clinical practice and provides justification to payers for reimbursement on the basis of the clearly demonstrated added value of the new intervention.

Clinical Outcome Assessments: Conceptual Foundation-Report of the ISPOR Clinical Outcomes Assessment - Emerging Good Practices for Outcomes Research Task Force.

An outcome assessment, the patient assessment used in an endpoint, is the measuring instrument that provides a rating or score (categorical or continuous) that is intended to represent some aspect of the patient's health status. Outcome assessments are used to define efficacy endpoints when developing a therapy for a disease or condition. Most efficacy endpoints are based on specified clinical assessments of patients. When clinical assessments are used as clinical trial outcomes, they are called clinical outcome assessments (COAs). COAs include any assessment that may be influenced by human choices, judgment, or motivation. COAs must be well-defined and possess adequate measurement properties to demonstrate (directly or indirectly) the benefits of a treatment. In contrast, a biomarker assessment is one that is subject to little, if any, patient motivational or rater judgmental influence. This is the first of two reports by the ISPOR Clinical Outcomes Assessment - Emerging Good Practices for Outcomes Research Task Force. This report provides foundational definitions important for an understanding of COA measurement principles. The foundation provided in this report includes what it means to demonstrate a beneficial effect, how assessments of patients relate to the objective of showing a treatment's benefit, and how these assessments are used in clinical trial endpoints. In addition, this report describes intrinsic attributes of patient assessments and clinical trial factors that can affect the properties of the measurements. These factors should be considered when developing or refining assessments. These considerations will aid investigators designing trials in their choice of using an existing assessment or developing a new outcome assessment. Although the focus of this report is on the development of a new COA to define endpoints in a clinical trial, these principles may be applied more generally. A critical element in appraising or developing a COA is to describe the treatment's intended benefit as an effect on a clearly identified aspect of how a patient feels or functions. This aspect must have importance to the patient and be part of the patient's typical life. This meaningful health aspect can be measured directly or measured indirectly when it is impractical to evaluate it directly or when it is difficult to measure. For indirect measurement, a concept of interest (COI) can be identified. The COI must be related to how a patient feels or functions. Procedures are then developed to measure the COI. The relationship of these measurements with how a patient feels or functions in the intended setting and manner of use of the COA (the context of use) could then be defined. A COA has identifiable attributes or characteristics that affect the measurement properties of the COA when used in endpoints. One of these features is whether judgment can influence the measurement, and if so, whose judgment. This attribute defines four categories of COAs: patient reported outcomes, clinician reported outcomes, observer reported outcomes, and performance outcomes. A full description as well as explanation of other important COA features is included in this report. The information in this report should aid in the development, refinement, and standardization of COAs, and, ultimately, improve their measurement properties.

Pain palliation measurement in cancer clinical trials: the US Food and Drug Administration perspective.

BACKGROUND: Pain palliation resulting from antitumor therapy provides direct evidence of treatment benefit when combined with evidence of antitumor activity. The US Food and Drug Administration (FDA) previously issued guidance regarding the use of patient-reported outcome (PRO) measures to support labeling claims. The purpose of this article is to identify common challenges and key design strategies when measuring pain palliation in antitumor therapy clinical trials that are consistent with PRO Guidance principles. METHODS: Antitumor clinical protocols submitted to the FDA between 1995 and 2012 that included pain palliation as a primary or secondary endpoint were reviewed. Challenges in critical trial design components were identified. Design strategies consistent with PRO Guidance principles are proposed. RESULTS: The challenges identified were measurement of pain intensity and analgesic use, enrollment eligibility criteria, data collection methods, responder definitions, missing data, and blinding. Strategies included the use of well-defined, reliable, PRO assessments of pain intensity and analgesics; ensuring that enrollment criteria define patients with clinically significant pain attributable to cancer on an optimal analgesic regimen; defining responders using both pain and analgesic use criteria; incorporating an analysis of tumor response to support evidence of pain response; and minimizing missing data and inadvertent unblinding. CONCLUSIONS: Improvement in cancer-related pain resulting from antitumor therapy is an important treatment benefit that can support drug approval and labeling claims when adequately measured if study results demonstrate statistically and clinically significant findings. Sponsors are encouraged to discuss pain palliation assessment methods with the FDA early in and throughout product development.

Patient-Centered Core Impacts Sets (PC-CIS): What They Are and What They Are Not.

Letter to the Editor We are writing regarding the Innovations in Pharmacy commentary entitled, "Evidentiary Standards for Patient-Centered Core Impact Value Claims."(1) We thank Dr. Langley for commenting on the National Health Council's work on patient-centered core impact sets (PC-CIS), an initiative spearheaded by the nonprofit organization and its membership with multi-stakeholder representation and input.(2-4) While we have tried to be clear and transparent about the intent of PC-CIS, the commentary made it apparent to us we need to (and will) do more to be explicit about what a PC-CIS is and is not, and its possible downstream uses. We believe the PC-CIS concept was misrepresented in the commentary and want to provide clarification for readers so they can consider the merits of the initiative for themselves.

Content validity--establishing and reporting the evidence in newly developed patient-reported outcomes (PRO) instruments for medical product evaluation: ISPOR PRO good research practices task force report: part 1--eliciting concepts for a new PRO instrument.

The importance of content validity in developing patient reported outcomes (PRO) instruments is stressed by both the US Food and Drug Administration and the European Medicines Agency. Content validity is the extent to which an instrument measures the important aspects of concepts that developers or users purport it to assess. A PRO instrument measures the concepts most significant and relevant to a patient's condition and its treatment. For PRO instruments, items and domains as reflected in the scores of an instrument should be important to the target population and comprehensive with respect to patient concerns. Documentation of target population input in item generation, as well as evaluation of patient understanding through cognitive interviewing, can provide the evidence for content validity. Developing content for, and assessing respondent understanding of, newly developed PRO instruments for medical product evaluation will be discussed in this two-part ISPOR PRO Good Research Practices Task Force Report. Topics include the methods for generating items, documenting item development, coding of qualitative data from item generation, cognitive interviewing, and tracking item development through the various stages of research and preparing this tracking for submission to regulatory agencies. Part 1 covers elicitation of key concepts using qualitative focus groups and/or interviews to inform content and structure of a new PRO instrument. Part 2 covers the instrument development process, the assessment of patient understanding of the draft instrument using cognitive interviews and steps for instrument revision. The two parts are meant to be read together. They are intended to offer suggestions for good practices in planning, executing, and documenting qualitative studies that are used to support the content validity of PRO instruments to be used in medical product evaluation.

Content validity--establishing and reporting the evidence in newly developed patient-reported outcomes (PRO) instruments for medical product evaluation: ISPOR PRO Good Research Practices Task Force report: part 2--assessing respondent understanding.

The importance of content validity in developing patient reported outcomes (PRO) instruments is stressed by both the US Food and Drug Administration and the European Medicines Agency. Content validity is the extent to which an instrument measures the important aspects of concepts developers or users purport it to assess. A PRO instrument measures the concepts most relevant and important to a patient's condition and its treatment. For PRO instruments, items and domains as reflected in the scores of an instrument should be important to the target population and comprehensive with respect to patient concerns. Documentation of target population input in item generation, as well as evaluation of patient understanding through cognitive interviewing, can provide the evidence for content validity. Part 1 of this task force report covers elicitation of key concepts using qualitative focus groups and/or interviews to inform content and structure of a new PRO instrument. Building on qualitative interviews and focus groups used to elicit concepts, cognitive interviews help developers craft items that can be understood by respondents in the target population and can ultimately confirm that the final instrument is appropriate, comprehensive, and understandable in the target population. Part 2 details: 1) the methods for conducting cognitive interviews that address patient understanding of items, instructions, and response options; and 2) the methods for tracking item development through the various stages of research and preparing this tracking for submission to regulatory agencies. The task force report's two parts are meant to be read together. They are intended to offer suggestions for good practice in planning, executing, and documenting qualitative studies that are used to support the content validity of PRO instruments to be used in medical product evaluation.

Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations.

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.

Evolution of clinical trials for irritable bowel syndrome: issues in end points and study design.

Irritable bowel syndrome (IBS) involves a broad range of physiological and psychological alterations that may affect brain-gut dysregulation, gut function, visceral perception, and mucosal integrity and function. Despite advances in our understanding of basic neuroenteric mechanisms and the role of effectors and transmitters in the brain-gut axis, a reliable biologic marker of IBS has yet to be identified. IBS diagnosis and status depend entirely on an assessment of IBS signs and symptoms. This has made development of optimal end points and study design for evaluation of efficacy of IBS drugs a challenge. This article addresses three main topics: the evolution of primary end points for IBS clinical trials; a potential path forward for IBS end points in new clinical trials; and recommendations for the future development of patient-reported outcome (PRO) instruments for use in IBS clinical trials.

Interpretation of chronic pain clinical trial outcomes: IMMPACT recommended considerations.

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.

Interpreting the clinical importance of treatment outcomes in chronic pain clinical trials: IMMPACT recommendations.

UNLABELLED: 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.

A Comparison of the Assay Sensitivity of Average and Worst Pain Intensity in Pharmacologic Trials: An ACTTION Systematic Review and Meta-Analysis.

Identifying methods to improve assay sensitivity in randomized clinical trials (RCTs) may facilitate the discovery of efficacious pain treatments. RCTs evaluating pain treatments typically use average pain intensity (API) or worst pain intensity (WPI) as the primary efficacy outcome. However, little evidence is available comparing the assay sensitivity of these 2 measures. In this systematic review and meta-analysis, we comprehensively reviewed all low back pain, osteoarthritis pain, fibromyalgia, diabetic peripheral neuropathy pain, and postherpetic neuralgia RCTs that used a parallel group design. Eligibility required: 1) primary RCT report published between 1980 and 2016, 2) comparing 1 or more active, efficacious pharmacologic pain treatment(s) with placebo, and 3) providing data on the standardized effect size (SES) for API as well as WPI for all treatment arms. Twenty-seven active versus placebo comparisons were identified in 23 eligible articles. Using a random-effects meta-analysis, API SES and WPI SES did not differ significantly (difference = -.021, 95% confidence interval = -.047 to .004, P = .12). The findings indicate that, depending on the objectives of the study, either API or WPI could be used as a primary outcome measure in clinical trials for the chronic pain conditions included in this analysis. PERSPECTIVE: Understanding the comparative assay sensitivity of API and WPI may advance pain treatment research. A meta-analysis of trials of efficacious pharmacologic treatments in 5 pain conditions did not show a statistically significant difference between the assay sensitivity of API and WPI.

Challenges to use of health-related quality of life for Food and Drug Administration approval of anticancer products.

The U.S. Food and Drug Administration (FDA) approves labeling claims of drug efficacy based on substantial evidence of clinical benefit demonstrated in adequate and well-controlled investigations. Patient-reported outcomes (PROs) may support marketing claims of clinical benefit, either alone or with other study endpoints. Health-related quality of life (HRQL) is a PRO that comprehensively measures patients' reported health status. We present an overview of why HRQL-based efficacy claims have not to date been accepted by the FDA for inclusion in anticancer product labels. Persistent challenges to allowance of such claims include shortcomings in randomization and blinding of clinical trials, missing data, statistical multiplicity, and unclear intrinsic meaning of selected HRQL findings.

Clinical trial endpoints in ovarian cancer: report of an FDA/ASCO/AACR Public Workshop.

OBJECTIVE: The unique characteristics of cancer, particularly issues involving the use of surrogate endpoints in clinical trials, present special challenges in the development of cancer drugs. In response, the U.S. Food and Drug Administration (FDA) has partnered with the American Society of Clinical Oncology, the American Association for Cancer Research, and the American Society of Hematology to conduct public workshops evaluating potential endpoints for drug approvals for the most common tumor types. METHODS: A workshop evaluating potential endpoints in ovarian cancer drug research was held in Bethesda, Maryland, in April 2006. Invited experts presented research findings and discussed endpoints in trials of drugs for treatment of Stage III and IV ovarian cancer. RESULTS: The panel responded to specific questions from FDA, discussing use of progression-free survival as a surrogate for overall survival and use of CA-125 levels as an indicator of response. Panel members also addressed endpoints in first-line therapy, second-line and subsequent therapy, and maintenance therapy. CONCLUSION: Expert commentary provided by panel members will inform FDA's draft guidance on clinical endpoints for cancer drug approvals and will be discussed at meetings of the FDA's Oncologic Drugs Advisory Committee. FDA intends to develop a set of principles that can be used to define efficacy standards for drugs used to treat ovarian and other cancers.

Patient-reported outcomes to support medical product labeling claims: FDA perspective.

This article concerns development and use of patient-reported outcomes (PROs) in clinical trials to evaluate medical products. A PRO is any report coming directly from patients, without interpretation by physicians or others, about how they function or feel in relation to a health condition and its therapy. PRO instruments are used to measure these patient reports. PROs provide a unique perspective on medical therapy, because some effects of a health condition and its therapy are known only to patients. Properly developed and evaluated PRO instruments also have the potential to provide more sensitive and specific measurements of the effects of medical therapies, thereby increasing the efficiency of clinical trials that attempt to measure the meaningful treatment benefits of those therapies. Poorly developed and evaluated instruments may provide misleading conclusions or data that cannot be used to support product labeling claims. We review selected major challenges from Food and Drug Administration's perspective in using PRO instruments, measures, and end points to support treatment benefit claims in product labeling. These challenges highlight the need for sponsors to formulate desired labeling claim(s) prospectively, to acquire and document information needed to support these claim(s), and to identify existing instruments or develop new and more appropriate PRO instruments for evaluating treatment benefit in the defined population in which they will seek claims.

Development and psychometric validation of the Nausea/Vomiting Symptom Assessment patient-reported outcome (PRO) instrument for adults with secondary hyperparathyroidism.

BACKGROUND: We developed the Nausea/Vomiting Symptom Assessment (NVSA©) patient-reported outcome (PRO) instrument to capture patients' experience with nausea and vomiting while on calcimimetic therapy to treat secondary hyperparathyroidism (SHPT) related to end-stage kidney disease. This report summarizes the content validity and psychometric validation of the NVSA©. METHODS: The two NVSA© items were drafted by two health outcomes researchers, one medical development lead, and one regulatory lead: it yields three scores: the number of days of vomiting or nausea per week, the number of vomiting episodes per week, and the mean severity of nausea. An eight-week prospective observational study was conducted at ten dialysis centers in the U.S. with 91 subjects. Criterion measures included in the study were the Functional Living Index-Emesis, Kidney Disease Quality of Life Instrument, EQ-5D-5 L, Static Patient Global Assessment, and Patient Global Rating of Change. Analyses included assessment of score distributions, convergent and known-groups validity, test-retest reliability, ability to detect change, and thresholds for meaningful change. RESULTS: Qualitative interviews verified that the NVSA© captures relevant aspects of nausea and vomiting. Patients understood the NVSA© instructions, items, and response scales. Correlations between the NVSA© and related and unrelated measures indicated strong convergent and discriminant validity, respectively. Mean differences between externally-defined vomiting/nausea groups supported known-groups validity. The scores were stable in subjects who reported no change on the Patient Global Rating of Change indicating sufficient test-retest reliability. The no-change group had mean differences and effect sizes close to zero; mean differences were mostly positive for a worsening group and mostly negative for the improvement group with predominantly medium or large effect sizes. Preliminary thresholds for meaningful worsening were 0.90 days for number of days of vomiting or nausea per week, 1.20 for number of episodes of vomiting per week, and 0.40 for mean severity of nausea. CONCLUSIONS: The NVSA© instrument demonstrated content validity, convergent and known-groups validity, test-retest reliability, and the ability to detect change. Preliminary thresholds for minimally important change should be further refined with additional interventional research. The NVSA© may be used to support study endpoints in clinical trials comparing the nausea/vomiting profile of novel SHPT therapies.

Measures That Identify Prescription Medication Misuse, Abuse, and Related Events in Clinical Trials: ACTTION Critique and Recommended Considerations.

Accurate assessment of inappropriate medication use events (ie, misuse, abuse, and related events) occurring in clinical trials is an important component in evaluating a medication's abuse potential. A meeting was convened to review all instruments measuring such events in clinical trials according to previously published standardized terminology and definitions. Only 2 approaches have been reported that are specifically designed to identify and classify misuse, abuse, and related events occurring in clinical trials, rather than to measure an individual's risk of using a medication inappropriately: the Self-Reported Misuse, Abuse, and Diversion (SR-MAD) instrument and the Misuse, Abuse, and Diversion Drug Event Reporting System (MADDERS). The conceptual basis, strengths, and limitations of these methods are discussed. To our knowledge, MADDERS is the only system available to comprehensively evaluate inappropriate medication use events prospectively to determine the underlying intent. MADDERS can also be applied retrospectively to completed trial data. SR-MAD can be used prospectively; additional development may be required to standardize its implementation and fully appraise the intent of inappropriate use events. Additional research is needed to further demonstrate the validity and utility of MADDERS as well as SR-MAD. PERSPECTIVE: Identifying a medication's abuse potential requires assessing inappropriate medication use events in clinical trials on the basis of a standardized event classification system. The strengths and limitations of the 2 published methods designed to evaluate inappropriate medication use events are reviewed, with recommended considerations for further development and current implementation.

The Potential Role of Sensory Testing, Skin Biopsy, and Functional Brain Imaging as Biomarkers in Chronic Pain Clinical Trials: IMMPACT Considerations.

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.

Patient phenotyping in clinical trials of chronic pain treatments: IMMPACT recommendations.

There is tremendous interpatient variability in the response to analgesic therapy (even for efficacious treatments), which can be the source of great frustration in clinical practice. This has led to calls for "precision medicine" or personalized pain therapeutics (ie, empirically based algorithms that determine the optimal treatments, or treatment combinations, for individual patients) that would presumably improve both the clinical care of patients with pain and the success rates for putative analgesic drugs in phase 2 and 3 clinical trials. However, before implementing this approach, the characteristics of individual patients or subgroups of patients that increase or decrease the response to a specific treatment need to be identified. The challenge is to identify the measurable phenotypic characteristics of patients that are most predictive of individual variation in analgesic treatment outcomes, and the measurement tools that are best suited to evaluate these characteristics. In this article, we present evidence on the most promising of these phenotypic characteristics for use in future research, including psychosocial factors, symptom characteristics, sleep patterns, responses to noxious stimulation, endogenous pain-modulatory processes, and response to pharmacologic challenge. We provide evidence-based recommendations for core phenotyping domains and recommend measures of each domain.

Pain intensity rating training: results from an exploratory study of the ACTTION PROTECCT system.

Clinical trial participants often require additional instruction to prevent idiosyncratic interpretations regarding completion of patient-reported outcomes. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership developed a training system with specific, standardized guidance regarding daily average pain intensity ratings. A 3-week exploratory study among participants with low-back pain, osteoarthritis of the knee or hip, and painful diabetic peripheral neuropathy was conducted, randomly assigning participants to 1 of 3 groups: training with human pain assessment (T+); training with automated pain assessment (T); or no training with automated pain assessment (C). Although most measures of validity and reliability did not reveal significant differences between groups, some benefit was observed in discriminant validity, amount of missing data, and ranking order of least, worst, and average pain intensity ratings for participants in Group T+ compared with the other groups. Prediction of greater reliability in average pain intensity ratings in Group T+ compared with the other groups was not supported, which might indicate that training produces ratings that reflect the reality of temporal pain fluctuations. Results of this novel study suggest the need to test the training system in a prospective analgesic treatment trial.