Situation: The condition of interest is variably defined.
Example: The disease, such as psoriatic arthritis, is complex.
Problem: There is no single symptom, sign, or measurement that suffices to make a diagnosis of the disease with certainty. Instead, a set of diagnostic criteria (symptoms, signs, imaging results, and laboratory measures) is used to identify the disease, which will unavoidably be differentially applied across studies.Imperfect Reference Standard: Setting 2Trikalinos TA, Balion TA. Options for summarizing medical test performance in the absence of a “gold standard.”
In: Methods guide for medical test reviews. Available at www.effectivehealthcare.ahrq.gov/medtestsguide.cfm.