Cognitive and gender bias in primary care spondyloarthritis diagnosis: case simulation-based research

How primary care physicians (PCPs) cognitively approach the diagnostic process of spondyloarthritis (SpA) remains poorly documented. This study aims to analyze their clinical reasoning, decision-making, and potential cognitive and gender biases in identifying axial (axSpA) and peripheral (pSpA) forms. We designed a qualitative study using online structured electronic questionnaire with 46 PCPs from the Spanish National Health System. Four cases-based simulations were presented: a male/female patient (1) 30-year-old with one-year low back pain (axSpA) and (2) 25-year-old with three-month left knee pain and left ankle pain (pSpA). Case information was provided sequentially. Following each section, participants supported their clinical reasoning and diagnostic decisions. Responses were analyzed alongside identified differential diagnoses and potential cognitive and gender biases. In the clinical case assessments, axSpA was correctly diagnosed in 11 out of 12 participants for the female case and in 7 out of 10 for the male case. In contrast, none of the participants correctly diagnosed the pSpA cases, regardless of patient sex. Distinct diagnostic reasoning patterns emerged based on the patient’s sex. In axSpA female cases, pain was initially interpreted as functional by 6 out of 12 participants, compared to 3 out of 10 in male cases. This gender bias was reflected in a tendency to attribute young women’s symptoms to psychological or nonspecific causes, in the clinicians’ perceived absence of overt red flags. Patterns consistent with anchoring bias were identified in diagnostic assessment, including persistence of initial interpretations even after objective inflammatory markers were reported, despite these tests often not having been initially requested by the participants. In pSpA cases, diagnostic reasoning showed patterns consistent with availability bias, with interpretations that appeared to be shaped by familiarity with sex —and age— related conditions. In women, pSpA was frequently misclassified as juvenile arthritis or vague inflammatory syndromes. In men, diagnoses emphasized contextual risk factors —such as sexual history or occupational strain— leading to misclassification as reactive arthritis or mechanical disorders. Findings indicate that diagnostic reasoning for spondyloarthritis in primary care may be shaped not only by clinical evidence but also by implicit biases related to patients’ sex, age and contextual factors. Addressing these influences requires targeted educational strategies that foster reflective, evidence-based diagnostic practices and integrate a gender-sensitive approach into clinical judgment.