A randomized trial of hypothesis-driven vs screening neurologic examination

We hypothesized that trainees would perform better using a hypothesis-driven rather than a traditional screening approach to the neurologic examination.

We randomly assigned 16 medical students to perform screening examinations of all major aspects of neurologic function or hypothesis-driven examinations focused on aspects suggested by the history. Each student examined 4 patients, 2 of whom had focal deficits. Outcomes of interest were the correct identification of patients with focal deficits, number of specific deficits detected, and examination duration. Outcomes were assessed by an investigator blinded to group assignments. The McNemar test was used to compare the sensitivity and specificity of the 2 examination methods.

Sensitivity was higher with hypothesis-driven examinations than with screening examinations (78% vs 56%; p = 0.046), although specificity was lower (71% vs 100%; p = 0.046). The hypothesis-driven group identified 61% of specific examination abnormalities, whereas the screening group identified 53% (p = 0.008). Median examination duration was 1 minute shorter in the hypothesis-driven group (7.0 minutes vs 8.0 minutes; p = 0.13).

In this randomized trial comparing 2 methods of neurologic examination, a hypothesis-driven approach resulted in greater sensitivity and a trend toward faster examinations, at the cost of lower specificity, compared with the traditional screening approach. Our findings suggest that a hypothesis-driven approach may be superior when the history is concerning for an acute focal neurologic process.