Residents should not independently perform focused abdominal sonography for trauma after 10 training examinations.

OBJECTIVES To assess whether 10 focused abdominal sonography for trauma (FAST) examinations could be used as a minimum standard for training, as suggested previously. METHODS This was a retrospective review of patients with abdominal trauma who underwent resident-performed FAST examinations before surgical or Department of Radiology evaluation. RESULTS Six hundred ninety-eight patients were examined by resident-performed FAST followed by reference standard evaluations. Four hundred twelve patients were evaluated by residents who previously performed 10 FAST examinations; 154 were evaluated by 29 residents performing their 11th through 30th examinations; and 258 were evaluated by 10 residents performing their 31st and subsequent examinations. The results of resident-performed FAST for intraperitoneal free fluid were as follows: 11 to 20 examinations--sensitivity, 73.9% (95% confidence interval, 51.3%-88.9%); specificity, 98.8% (92.5%-99.9%); true-positive findings, 17; true-negative, 81; false-positive, 1; false-negative, 6; total patients, 105; 21 to 30 examinations--sensitivity, 100% (73.2%-100%); specificity, 97.1% (83.3%-99.9%); true-positive, 14; true-negative, 34; false-positive, 1; false-negative, 0; total patients, 49; 31 and more examinations--sensitivity, 94.8% (88.6%-97.9%); specificity, 98.6% (94.5%-99.8%); true-positive, 110; true-negative, 140; false-positive, 2; false-negative, 6; total patients, 258. CONCLUSIONS The suggestion that 10 examinations could be used as a minimum standard for training in FAST examinations was not validated.