Background:
Regulators’ guidance documents for the development and validation of patient reported outcomes (PROs) advise the use of conceptual frameworks, which outline the structure of the concept that a PRO aims to measure. It is unknown if currently available PROs are based on conceptual frameworks. This study, limited to a specific case, aimed (i) to identify conceptual frameworks of physical activity in chronic respiratory patients or similar populations (chronic heart disease patients or the elderly), and (ii) to assess if the development and validation of PROs to measure physical activity in these populations were based on a conceptual framework of physical activity.
Methods:
Two systematic reviews were conducted through search in Medline, Embase, Psychinfo, and Cinahl databases up to January 2010.
Results:
In the first review only 2 references, identified from 581 references about physical activity in the defined populations, provided a conceptual framework of physical activity in COPD patients. In the second review, out of 103 studies developing PROs to measure physical activity or related constructs, none of them was based on a conceptual framework of physical activity.
Conclusions:
These findings raise concerns about how the large body of evidence from studies that use physical activity PRO instruments should be evaluated by health care providers, guideline developers, and regulatory bodies.