Low doses of colistimethate: Don't rush in!

To the Editor—Bennatar et al compared clinical outcomes between so called high-dose and low-dose regimens of intravenous colistimethate [1]. Although 28-day mortality tended to be lower for high-dose than for low-dose regimens (34.7% vs 42.9%, respectively;P = .09), they found no significant difference either after adjustment in a multivariate model or after matching patients by a propensity score. Beyond the limitations addressed in the editorial commentary by Pogue et al [2], we believe there are other critical aspects that may have favored the null hypothesis.