Clinical assessment before PET/computed tomography: frequency and diagnostic impact

To investigate how often referring physicians perform history taking and physical examination before PET/computed tomography (PET/CT) referral, and whether their absence influences clinical reasoning quality or diagnostic yield.

Patients undergoing PET/CT at a tertiary academic hospital were asked whether their referring physician had conducted history taking and physical examination before referral. Associations between omission of clinical assessment and clinical reasoning quality or PET/CT positivity (defined as PET/CT findings relevant to the clinical indication) were analyzed using multivariable regression.

Among 288 patients (median age: 66 years; 54% male), history taking was omitted in 18.2% and physical examination in 47.7%. For history taking, only referrals from pulmonology were significantly more likely to include history taking [odds ratio (OR): 4.708, P = 0.033]. For physical examination, referrals from residents were more likely to include physical examination (OR: 2.355, P = 0.022), as were surgical departments (OR: 8.527, P = 0.030), requests for new clinical complaints (OR: 2.303, P = 0.008), and total-body PET/CT scans (OR: 1.870, P = 0.037), whereas urology referrals were less likely (OR: 0.019, P = 0.008). Neither omission of history taking nor physical examination was associated with clinical reasoning quality or PET/CT positivity (all P > 0.15).

A relevant proportion of patients referred for PET/CT did not receive history taking or physical examination. While omission of these assessments did not appear to affect the clinical reasoning quality of the referring physicians or PET/CT yield, it may limit the contextual information available for interpreting imaging results.