Pocket-Sized Ultrasound as an Aid to Physical Diagnosis for Internal Medicine Residents: A Randomized Trial

Abstract

BACKGROUND: Proficiency and self-confidence in the physical examination is poor among internal medicine residents and interest in ultrasound technology has expanded. OBJECTIVE: We aimed to determine whether a pocket-sized ultrasound improves the diagnostic accuracy and confidence of residents after a 3-h training session and 1 month of independent practice. DESIGN: This was a randomized parallel group controlled trial. PARTICIPANTS: Forty internal medicine residents in a single program at an academic medical center participated in the study. INTERVENTION: Three hours of training on use of pocket-sized ultrasound was followed by 1 month of independent practice. MAIN MEASURES: The primary outcome was a comparison of the diagnostic accuracy of a physical exam alone versus a physical examination augmented with a pocket-sized ultrasound. Other outcomes included confidence in exam findings and a survey of attitudes towards the physical exam and the role of ultrasound. KEY RESULTS: Residents in the intervention group using a pocket-sized ultrasound correctly identified an average of 7.6 of the 17 abnormal findings (accuracy rate of 44.9 %). Those in the control group correctly identified an average of 6.4 abnormal findings (accuracy rate of 37.6 %, p = 0.11). Residents in the intervention group identified on average 15.9 findings as abnormal when no abnormality existed (false positive rate of 16.8 %). Those in the control group incorrectly identified an average of 15.5 positive findings (false positive rate of 16.3 %). There was no difference between groups regarding self-assessed confidence in physical examination. Residents in the intervention group identified 6.1 of 13 abnormal cardiac findings versus the control group’s 4.5 of 13, an accuracy rate of 47.0 % versus 34.6 % (p = 0.023). CONCLUSIONS: The diagnostic ability of internal medicine residents did not significantly improve with use of a pocket-sized ultrasound device after a 3-h training session and 1 month of independent practice. Trial Registration: clinicaltrials.gov: number NCT01948076; URL http://clinicaltrials.gov/ct2/show/study/NCT01948076?term=ultrasound+physical+exam&rank=2.