How accurately do we estimate patients' weight in emergency departments?

OBJECTIVE To assess the accuracy of estimates of patients' weight made by p hysicians, nurses, and patients themselves in emergency departments. DESIGN Observational prospective study. SETTING Tertiary referral centre in Vancouver, BC. PARTICIPANTS Eleven attending physicians, 26 nurses, and a convenience samp le of 117 patients. INTERVENTIONS Patients themselves, attending physicians, and nurses indepen dently estimated the weight of 117 patients. An investigator weighed each p atient. MAIN OUTCOME MEASURES Mean error was determined by subtracting actual weigh t from estimated weight and dividing by actual weight; 95% confidence inter vals (CI) were calculated. RESULTS Mean error in estimates was 3.1% (95% CI 2.7 to 3.5) for patients, 8.4% for nurses (CI 7.6 to 9.2), and 8.1% (CI 7.1 to 9.1) for physicians. W eight was estimated within 5% of actual weight by 32% of nurses, 39% of phy sicians, and 82% of patients. Weight was estimated within 10% of actual wei ght by 66% of nurses, 66% of physicians, and 97% of patients. Estimates out by more than 15% were made by 11% of nurses, 16% of physicians, and 1% of patients. CONCLUSIONS Patient estimates were mast accurate. Physician and nurse estim ates were unreliable.