Objective: The objective of this study was to develop a method for evaluating patient-relevant outcomes of interventions for preventing migraine attacks, followed by an assessment of the content validity of a new patient-reported outcome (PRO) instrument: the Migraine Functional Impact Questionnaire (MFIQ).
Background: The aim of preventive treatments for migraine is not only to reduce migraine frequency, but also to restore patients' ability to function and improve quality of life.
Methods: A multi-stage process based on best practice methods and regulatory guidelines for ensuring content validity of PRO instruments for evaluating treatment benefit was followed. Qualitative concept elicitation interviews conducted to understand the experiences of adults with migraine underpinned the development of the instrument. The initial stage included the development of a conceptual disease model (CDM) based on information from these interviews. This CDM was used to identify the concepts of interests (COI) to evaluate outcomes of preventive treatments. The results of the interviews were also used in stage 2, to develop a measurement framework for collecting data about these COI. In the third stage, existing instruments were reviewed for coverage of the concepts in the framework and evidence of concept elicitation to the point of saturation, to support content validity. In the fourth stage, an instrument was drafted to evaluate concepts in the framework, based on the qualitative data collected from the interviews. Following a review by clinical and translation experts, the new instrument was tested in adults with migraine in the fifth stage using 2 rounds of cognitive interviews, and was modified based on interview feedback. In the last stage, the instrument was linguistically adapted, using methods recommended for PRO instruments, to ensure conceptual equivalence of language versions for use in international studies. Each language version was tested in at least 5 native speakers using cognitive interviews.
Results: Results from the concept elicitation interviews suggested that migraine had an impact on various aspects of functioning. A conceptual framework for evaluating functional outcomes was developed for the concept selected based on a review of the CDM - physical and emotional functioning, every day activities, and social/leisure activities. Existing PROs lacked coverage of some concepts in the conceptual framework, had recall periods that were inappropriate for capturing the experience of COI or did not have evidence of content validity. A novel PRO instrument, the MFIQ, was developed to address these gaps. Cognitive interviews with 9 adults with migraine resulted in minor changes to the items of the MFIQ, and a final round of 8 interviews confirmed the changes were acceptable and supported its validity. The interviews conducted to test linguistic adaptations confirmed conceptual equivalence in the 25 countries evaluated.
Conclusions: Development of the MFIQ followed best measurement practices to ensure content validity and followed regulatory guidelines for PRO instruments to evaluate benefits of treatments. The MFIQ was developed for use in clinical trials or clinical practice settings to track outcomes of preventive treatments that are most relevant to adults with migraine.
Keywords: Migraine; PRO; Qualitative interview; content validity; functioning; questionnaire.
© 2018 The Authors Headache: The Journal of Head and Face Pain published by Wiley Periodicals, Inc. on behalf of American Headache Society.