How accurate is weight estimation in the emergency department?

To determine the accuracy of medical staff, nursing staff and patients for estimating weight in an ED population.

This is a prospective, observational study. Medical staff, nursing staff and patients were asked to estimate patient weight that was then measured. The main outcome was average per cent error in weight estimation for each group.

Average per cent error in estimates was 3.9% for patients (95% CI 3.6-4.1%), 7.7% (95% CI 7.2-8.2%) for nurses and 11% (95% CI 10.2-11.7%) for physicians. Ninety-one per cent of patients (95% CI 90-93%), 78% of nurses (95% CI 75-80%) and 59% of physicians (95% CI 56-63%) made weight estimates accurate to within 10% of actual weight.

Patients are generally accurate in estimating their true weight and health care workers showed only moderate accuracy. Where possible, drug dose calculations should be based on measured weight and if this is not possible, patient estimate of weight should be sought. Health care worker estimation should be used only when this is not possible.