Given the need to standardize the objective structured clinical examination (OSCE), “patients” in the OSCE are typically actors without abnormal physical findings, which may reduce the face validity of the OSCE as an evaluation of clinical skills. In this study we used a ventriloscope® to simulate cardiac and respiratory findings, and explored the impact on psychometrics, cognitive load, and diagnostic performance on the OSCE station.

We randomly allocated 55 final-year medical students to either standard or ventriloscope®-enhanced format of a formative OSCE station on “acute onset dyspnea. In both formats students took a history from a standardized patient (SP), after which they either requested the physical examination findings (standard format) or performed cardiac and respiratory auscultation using a ventriloscope®. After completion of the OSCE station students rated their subjective cognitive load and raters used a global rating scale to evaluate students’ performance.

The standard OSCE format had difficulty index of 0.85 and discrimination index of 0.3, compared to 0.9 and 0.2 for the ventriloscope®-enhanced format. There was no significant difference between groups in either subjective rating of cognitive load after the dyspnea OSCE station (6.43 (2.02) vs. 6.39 (1.15), p = 0.9) or rating of students’ performance on the OSCE station (78.3 (9.1) vs. 79.0 (8.9), p = 0.8).

Use of a ventriloscope® can enhance the face validity of the OSCE as an evaluation of clinical skills without adversely affecting psychometrics or cognitive load.

1. McLaughlin K, Vitale G, Coderre S, Violato C, Wright B. Clerkship evaluation--what are we measuring? Med Teach. 2009;31:e36-9.

2. Castilano A, Haller N, Goliath C, Lecat P. The Ventriloscope: 'am I hearing things?' Med Teach. 2009;31:e97-101.

3. Verma A, Bhatt H, Booton P, Kneebone R. The Ventriloscope® as an innovative tool for assessing clinical examination skills: appraisal of a novel method of simulating auscultatory findings. Med Teach. 2011;33:e388-96.

4. Sweller J. Cognitive load during problem solving: effects on learning. Cog Sci. 1988;12:257-85. 5. Paas FGWC, van Merriënboer JJG. The efficiency of instructional conditions: an approach to combine mental effort and performance measures. Hum Factors. 1993;35:737-43.