Assuring the patient centeredness of patient-reported outcomes: content validity in medical product development and comparative effectiveness research.

Not all patient-reported outcomes (PROs) are patient centered, and not all patient-centered outcomes are patient reported. The essential characteristic of a patient-centered approach to outcome measurement is that it assesses concepts (i.e., healthrelated phenomena) that are considered most important by members of a given target population, based on direct input from representatives of that population. Concepts for measurement should not be selected based solely on convenience or interest to investigators. Patient-centered patient-reported outcome measures ust meet this criterion and also be meaningful and comprehenible to members of a population when administered, including mong those with diverse racial/cultural backgrounds and lower ducational/literacy levels. An example of a PRO measure that is not optimally patient entered is the Present Pain Intensity item of the McGill Pain Quesionnaire [1]. The Present Pain Intensity item has been used as a RO measure in multiple phase III clinical trials in the regulatory ontext (including serving as the basis for U.S. drug approval and abeling of the cancer drug mitoxantrone in 1996) [2]. This meaure, however, was initially developed for clinician reporting and ever underwent qualitative evaluation with direct patient input. he item asks respondents: