Montreal Accord on Patient-Reported Outcomes (PROs) use series–Paper 7: modern perspectives of measurement validation emphasize justification of inferences based on patient reported outcome scores

Obtaining the patient's view about the outcome of care is an essential component of patient-centered care. Many patient-reported outcome (PRO) instruments for different purposes have been developed since the 1960s. Measurement validation is fundamental in the development, evaluation, and use of PRO instruments. This paper provides a review of modern perspectives of measurement validation in relation to the followings three questions as applied to PROs: (1) What evidence is needed to warrant comparisons between groups and individuals? (2) What evidence is needed to warrant comparisons over time? and (3) What are the value implications, including personal and societal consequences, of using PRO scores? Measurement validation is an ongoing process that involves the accumulation of evidence regarding the justification of inferences, actions, and decisions based on measurement scores. These include inferences pertaining to comparisons between groups and comparisons over time as well as consideration of value implications of using PRO scores. Personal and societal consequences must be examined as part of a comprehensive approach to measurement validation. The answers to these three questions are fundamental to the the validity of different types of inferences, actions, and decisions made on PRO scores in health research, health care administration, and clinical practice.