Abstract 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.
Abstract 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.
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.
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.
The objective of the present research was to develop a single measure of the major symptoms of both neuropathic and non-neuropathic pain that can be used in studies of epidemiology, natural history, ...pathophysiologic mechanisms, and treatment response. We expanded and revised the Short-form McGill Pain Questionnaire (SF-MPQ) pain descriptors by adding symptoms relevant to neuropathic pain and by modifying the response format to a 0-10 numerical rating scale to provide increased responsiveness in longitudinal studies and clinical trials. The reliability, validity, and subscale structure of the revised SF-MPQ (SF-MPQ-2) were examined in responses from 882 individuals with diverse chronic pain syndromes and in 226 patients with painful diabetic peripheral neuropathy who participated in a randomized clinical trial. The data suggest that the SF-MPQ-2 has excellent reliability and validity, and the results of both exploratory and confirmatory factor analyses provided support for four readily interpretable subscales-continuous pain, intermittent pain, predominantly neuropathic pain, and affective descriptors. These results provide a basis for use of the SF-MPQ-2 in future clinical research, including clinical trials of treatments for neuropathic and non-neuropathic pain conditions.
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.
Abstract 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.
Abstract 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 andevaluated 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.
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.
Abstract 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.