There is need for a validated short, simple instrument to quantify chronic obstructive pulmonary disease (COPD) impact in routine practice to aid health status assessment and communication between patient and physician. Current health-related quality of life questionnaires provide valid assessment of COPD, but are complex, which limits routine use.The aim of the present study was to develop a short validated patient-completed questionnaire, the COPD Assessment Test (CAT), assessing the impact of COPD on health status. 21 candidate items identified through qualitative research with COPD patients were used in three prospective international studies (Europe and the USA, n51,503). Psychometric and Rasch analyses identified eight items fitting a unidimensional model to form the CAT. Items were tested for differential functioning between countries. Internal consistency was excellent: Cronbach's a50.88. Test re-test in stable patients (n553) was very good (intra-class correlation coefficient 0.8). In the sample from the USA, the correlation with the COPD-specific version of the St George's Respiratory Questionnaire was r50.80. The difference between stable (n5229) and exacerbation patients (n567) was five units of the 40-point scale (12%; p,0.0001).The CAT is a short, simple questionnaire for assessing and monitoring COPD. It has good measurement properties, is sensitive to differences in state and should provide a valid, reliable and standardised measure of COPD health status with worldwide relevance.

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.

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.

Recently, the FDA has encouraged testing of medications among pediatric patients during drug development. Pharmaceutical companies have responded by conducting more clinical trials among children, and researchers are becoming aware of the unique challenges of assessing pediatric health outcomes, including health-related quality of life (HRQL). Like adults, children experience effects of illness and treatment beyond physiologic outcomes. Further pediatric HRQL research is necessary to examine these broader psychosocial outcomes and provide a thorough understanding of the effects of treatment on children's health status. The purpose of the current review is to discuss key regulatory and methodologic developments and provide guidance for future research on pediatric HRQL. This review of pediatric HRQL assessment includes five sections: 1). recent pediatric regulatory developments in the United States; 2). issues in defining and conceptualizing pediatric HRQL, including the importance of contextual variables such as family and peer systems; 3). methodologic issues (e.g., the proxy question, developmental differences, response sets) with recommendations for addressing these issues in clinical trials; 4). validated generic and condition-specific pediatric HRQL measures; and 5). a recommendation for additional research on the HRQL impact of childhood psychiatric disorders. It is advocated that assessment of HRQL among children should be conducted regularly as an integral part of drug development.

BackgroundTo develop content validity of a comprehensive patient-reported outcome (PRO) measure following current best scientific methodology to standardize assessment of influenza (flu) symptoms in clinical research.MethodsStage I (Concept Elicitation): 1:1 telephone interviews with influenza-positive adults (≥18 years) in the US and Mexico within 7 days of diagnosis. Participants described symptom type, character, severity, and duration. Content analysis identified themes and developed the draft Flu-PRO instrument. Stage II (Cognitive Interviewing): The Flu-PRO was administered to a unique set of influenza-positive adults within 14 days of diagnosis; telephone interviews addressed completeness, respondent interpretation of items and ease of use.ResultsSamples: Stage I: N = 46 adults (16 US, 30 Mexico); mean (SD) age: 38 (19), 39 (14) years; % female: 56 %, 73 %; race: 69 % White, 97 % Mestizo. Stage II: N = 34 adults (12 US, 22 Mexico); age: 37 (14), 39 (11) years; % female: 50 %, 50 %; race: 58 % White, 100 % Mestizo. Symptoms: Symptoms identified by >50 %: coughing, weak or tired, throat symptoms, congestion, headache, weakness, sweating, chills, general discomfort, runny nose, chest (trouble breathing), difficulty sleeping, and body aches or pains. No new content was uncovered during Stage II; participants easily understood the instrument.ConclusionsResults show the 37-item Flu-PRO is a content valid measure of influenza symptoms in adults with a confirmed diagnosis of influenza. Research is underway to evaluate the suitability of the instrument for children and adolescents. This work can form the basis for future quantitative tests of reliability, validity, and responsiveness to evaluate the measurement properties of Flu-PRO for use in clinical trials and epidemiology studies.