The article "Serial CSF Corticotropin-Releasing Hormone Levels and Adrenocortical Activity in Combat Veterans With Posttraumatic Stress Disorder" by Dewleen G. Baker, M.D., et al. (April 1999, pp. 585–588) contains two errors on page 586. In the Results section, the sentence beginning on line 8 should read: "Mean CSF CRH concentrations were lower in smokers than in nonsmokers (43.7 pg/ml, SD=13.0, versus 52.1, SD=19.2), but the difference was not significant (F=–1.12, df=1, 16, p<0.31)"; and the sentence beginning on line 28 should read: "Although the mean 24-hour urinary free cortisol excretion was higher in the smokers (97.5 µg/24 hours, SD=57.3) than the nonsmokers (67.4 µg/24 hours, SD=19.7), the difference was not significant (t=–1.56, df=17)."