Latent Class Analysis: An Illustrative Application for Education in the Assessment of Resident Otoscopic Skills

Background.—There is no gold standard readily available in several components of the routine physical exam: one example is the otoscopic exam, where the gold standard is confirmation by tympanocentesis. Resident education does not typically include routine assessment by the gold standard, making estimates of trainee performance extremely difficult. This is one reason why the otoscopic examination is difficult to teach. Available techniques can assess diagnostic exams when there is no gold standard—one of these is latent class analysis.

Methods.—We use latent class analysis, a form of regression analysis, to compare the ability of pediatric residents to diagnose effusion with pediatric otolaryngologists and tympanometry. We briefly outline the technique of how to complete latent class analysis and provide an operational plan to use the method to assess resident performance.

Results.—The sensitivity and specificity of pediatric resident otoscopic examination to diagnose the presence of effusion was 72% and 84%, respectively. Pediatric otolaryngologist sensitivity and specificity was 91% and 82%; tympanometry had a sensitivity of 70% and specificity 76%. Our estimates of the performance of otolaryngologists and tympanometry to diagnose effusion were the same as previously reported when these diagnosticians have been compared with the gold standard of tympanocentesis.

Conclusions.—Latent class analysis can help estimate otoscopic examination performance of residents. This technique can be incorporated into assessment in medical education.

KEY WORDS:  housestaff , latent class analysis , otitis media , tympanic membrane