BACKGROUND: This study compares dose-response injury risk estimates for two control periods defined as the same 6-hour period the week prior and the set of all non-sleeping 6-hour periods over the past year.
METHOD: Dose-response injury risk estimates for the multiple match controls are generated via the application of a maximum-likelihood approach.
RESULTS: Injury risk associated with any (i.e., 1 drink or more) drinking 6 hours prior to injury was similar for the two control choices (last week and usual frequency). For 1-4 drinks, risk estimates were similar across control period definitions; for 5+ drinks, risk using the week prior as the control was nearly double that using the past 12 months as the control.
CONCLUSIONS: Although studies with smaller ns may benefit from the increase in precision from the use of the multiple control periods, results indicate that heavy drinking injury risk estimates should be used with caution.