The accuracy and cost of four methods of duplicate reading were evaluated. Eight radiologists interpreted 100 random chest radiographs. Using a third independent interpretation to resolve disagreements between pairs of readers ("Pseudoarbitration") was the most effective method overall, reducing errors 37%, increasing correct interpretations 18%, and adding 19% to the cost of an error-free interpretation. Resolving disagreements in facor of positive diagnoses was the best method for reducing omissions, but it almost doubled false-positive diagnoses. The choice between single and multiple interpretations must be evaluated in each clinical setting and should consider expected improvements in accuracy, implications for patient care, and additional costs.