Dimensionality of the Maintenance of Certification for Family Physicians Examination: Evidence of Construct Validity

The American Board of Family Medicine (ABFM) Maintenance of Certification for Family Physicians (MC-FP) examination is designed to measure a single construct: clinical decision-making abilities within the scope of practice of family medicine. Implied in the construct of clinical decision-making abilities is the ability to recall relevant elements from a large fund of pertinent medical knowledge. While clinical decision-making abilities could be perceived as comprising several separate constructs (eg, based upon clinical categories, organ systems, etc), that approach would require the development of multiple assessment scales with a passing criteria specific to each. Instead, the overarching construct of clinical decision-making ability, which encompasses those more specific areas, has been selected by the ABFM because it more closely mirrors the pass-fail decision process used to discern which candidates receive certification. In any instance, the construct that the ABFM attempts to measure needs to be sufficiently unidimensional in order to produce precise, error-free estimates of a candidate’s performance. This brief article will discuss the dimensionality of the MC-FP examination and its implications for construct validity, namely the validation that the examination accurately measures the ability of family physicians to make appropriate clinical decisions.