Several studies have shown that the standard error of measurement (SEM) can be used as an additional “safety net” to reduce the frequency of false-positive or false-negative student grading classifications. Practical examinations in clinical anatomy are often used as diagnostic tests to admit students to course final examinations. The aim of this study was to explore the diagnostic value of SEM using the likelihood ratio (LR) in establishing decisions about students with practical examination scores at or below the pass/fail cutoff score in a clinical anatomy course. Two hundred sixty-seven students took three clinical anatomy practical examinations in 2011. The students were asked to identify 40 anatomical structures in images and prosected specimens in the practical examination. Practical examination scores were then divided according to the following cutoff scores: 2, 1 SEM below, and 0, 1, 2 SEM above the pass score. The positive predictive value (+PV) and LR of passing the final examination were estimated for each category to explore the diagnostic value of practical examination scores. The +PV (LR) in the six categories defined by the SEM was 39.1% (0.08), 70.0% (0.30), 88.9% (1.04), 91.7% (1.43), 95.8% (3.00), and 97.8% (5.74), respectively. The LR of categories 2 SEM above/below the pass score generated a moderate/large shift in the pre- to post-test probability of passing. The LR increased the usefulness and practical value of SEM by improving confidence in decisions about the progress of students with borderline scores 2 SEM above/below the pass score in practical examinations in clinical anatomy courses. Anat Sci Educ. © 2013 American Association of Anatomists.