The ability of medical students to recognize heart sounds is alarmingly low (∼21%). We previously demonstrated students who listened to intensive repetition of abnormal heart sounds in a classroom setting achieved a proficiency score of 85%. This followup study investigated if similar results could be obtained using the Internet.
64 third year medical students were randomized to either an intervention (I) group (N=50) or control (C) group (N=14). The intervention students were instructed to download a digital audio file (mp3) from a web page. This file contained auditory recognition exercises of 4 basic cardiac murmurs (Aortic Stenosis, Aortic Regurgitation, Mital Regurgitation, Mitral Stenosis) and 2 extra heart sounds (S3, S4). Each heart sound was repeated 400 times interspersed with clinically relevant comments. The 14 control students downloaded a sham file with no auditory instruction. Two tests of auscultatory proficiency were administered: a pretest before the intervention and a posttest after the intervention. At both tests, all subjects listened to prerecorded heart sounds in a randomized sequence and wrote the name of the sound on blank answer sheets.
For the intervention students, the pretest proficiency score was 29.6 + 15.7% (Mean +SD) and increased significantly to 82.0 + 16.9% on the posttest (p<0.001). The average improvement was 52 points. No significant improvement was seen in controls: pretest 38.8 +/- 17.3% and posttest 44.6 +/- 17.6% p=0.15.
Third year medical students demonstrated dramatic improvement in cardiac auscultation after listening to a digital audio file downloaded via the internet. These improvements were equal to that obtained with classroom instruction using a similar approach of intensive repetition of abnormal sounds.
This study confirms to importance of intensive repetition in learning cardiac auscultation and demonstrates that this type of learning can be effectively communicated via the internet. This method of instruction is associated with significant cost savings and expanded geographic reach.
Michael Barrett, Shareholder Michael Barrett, MD has an ownership interest in MED-Ed Consulting, Inc.