This single blinded observational study compared the bispectral index (BIS) monitor with a validated pediatric sedation scale, the University of Michigan Sedation Scale (UMSS), to evaluate whether the BIS score can be used to judge the depth of sedation in pediatric outpatients. Thirty-eight children, with a mean age of 5.8 years, undergoing routine sedation for both noninvasive and gastrointestinal procedures, had simultaneous BIS and UMSS scores recorded. Sedation categories were defined as light, moderate, and deep for both UMSS and BIS. There was a moderate correlation between BIS and the UMSS, Spearman's r < -0.499. The correlation was poor for children receiving chloral hydrate, r < -0.213. The BIS score was not predictive of any specific UMSS score. The UMSS and BIS categories of sedation matched only 36% of the time. BIS underestimated the clinical level of sedation.