Evaluating the Diagnostic Accuracy of the Side-Lying Test for Posterior Canal BPPV: Sensitivity and Specificity Analysis.

Background objective: The side-lying (SL) test is a diagnostic maneuver used to identify posterior canal benign paroxysmal positional vertigo (PC-BPPV). It is often used as an alternative to the Dix-Hallpike (DH) test, particularly for patients who have mobility limitations. The objective of this study is to evaluate the sensitivity and specificity of the SL test in diagnosing PC-BPPV compared with the DH test.

Methods: A cohort of 320 patients presenting with symptoms of vertigo underwent both the SL test and the DL maneuver. Two groups-group A and group B-were randomly formed. Group A patients were assessed with first DL test, then SL test and group B patients were assessed with first SL then DH. The diagnostic accuracy of the SL test was assessed by determining its sensitivity and specificity in relation to the DH test, which served as the reference standard.

Results: The SL test demonstrated 95.1% sensitivity and 96.97% specificity in detecting posterior canal BPPV, with comparable diagnostic accuracy to the DH test. Chi-square test (140.34) also emphasized the statistical significance of these results. The DH test's AUC of 0.902 shows a high capacity to differentiate between cases with and without BPPV. On the other hand, the SL test shows even greater performance in distinguishing between BPPV and non-BPPV cases, as seen by its higher AUC of 0.960.

Conclusion: The SL test is a viable alternative to the DH test, offering similar sensitivity and specificity in diagnosing posterior canal BPPV. Its use may benefit patients with physical limitations.