Can ED staff accurately estimate the weight of adult patients?

Purpose: The purpose of the study was to determine the accuracy of adult weight estimates by emergency department personnel.
Basic Procedures: This was a prospective, nonrandomized, observational study in a university tertiary referral center. All patient care staff and all adult patients were eligible. Patients were weighed at the bedside, then staff were asked individually for estimates. Data were analyzed using SPSS general linear modeling procedures (SPSS, Chicago, IL) to obtain a generalized analysis of variance.
Main Findings: Eighty-seven staff provided 957 estimates on 241 patients. Providers were within 5% of true weight on 33% of estimates (95% confidence interval [CI], 28-38). In our a priori subgroups, a significant difference was noted only for body mass index (BMI); percentages of correct estimates were 16% (95% CI, 0-33; n = 33) for BMI < 18.5; 38% (95% CI, 33-43; n = 654) for 18.5 < or = BMI < or = 30; and 23% (95% CI, 17-30; n = 270) for BMI > 30 (P < .001).
Principal Conclusions: Emergency department personnel provided accurate weights in only 33% of estimates. Estimates became significantly less accurate in underweight and obese patients (defined by BMI).