The steroid-croup controversy: an analytic review of methodologic problems.

The reasons for the controversy regarding the use of corticosteroids to treat croup were reviewed by evaluating nine studies for their adequacy in meeting eight methodologic standards essential for reducing bias and distortion in clinical trials. Five studies employed diagnostic criteria for croup but none stratified patients with croup into acute laryngotracheitis and spasmodic croup, the two forms which account for the large majority of cases of croup. Only four studies used adequate doses of steroids, defined as 100 mg of cortisone or an equivalent. Only two studies developed clinically relevant choices for the outcome event. Although steroids may be helpful in certain types of croup, it is impossible to reach a definite conclusion about the efficacy of steroids, since all of the studies have major inadequacies in clinical trial design.