Validity and Diagnosis in Physical and Rehabilitation Medicine: Critical View and Future Perspectives.

Obtaining a diagnosis is an essential and integral part of physical and rehabilitation medicine in practice and research. Standardized psychometric properties are required of any classifications, diagnostic criteria, and diagnostic rules used. Physicians and researchers, in physical and rehabilitation medicine, need to understand these properties to determine the accuracy and consistency of their diagnosis. Although chronic musculoskeletal pain disorders are among the highly prevalent disorders seen in physical and rehabilitation medicine, limitations regarding existing diagnostic criteria for chronic musculoskeletal pain disorders still exist. Hence, the quest for developing diagnostic tools for chronic musculoskeletal pain that align with the standard properties remains open. These are discussed with an example for existing diagnostic criteria for fibromyalgia. This article primarily aimed to provide an overview of standard psychometric properties. A secondary aim was to critically appraise the tools currently used to diagnose chronic musculoskeletal pain disorders. The challenges and limitations of existing diagnostic tools are discussed. Potential approaches on how to improve the conceptualization of the construct of musculoskeletal pain disorders are also discussed. Adopting a network perspective, for example, can better constitute the disease instead of a single known underlying etiology for persistent or recurrent pain symptoms.