Idiographically determined versus standard absorption periods in alcohol administration studies.
BACKGROUND
Effects of alcohol vary depending on blood alcohol level and limb. Some researchers use standard absorption periods (SAPs) to determine when postdrinking experimental protocols should begin. Others use an idiographically determined absorption period (IDAP) based on criterion breath alcohol concentration (BrAC). We investigated and compared the characteristics of each method.


METHODS
Sixty-eight social drinkers (47% women) consumed a bolus dose of alcohol intended to raise BrAC to 0.08%. BrACs were recorded every 3 minutes until beginning to descend. Minutes to reach criterion BrAC (0.06%) and between-subjects postdrinking BrAC variability were analyzed.


RESULTS
Mean time to reach 0.06% BrAC was 22.9 +/- 14.6 minutes. Standard deviations in BrAC were 4 times greater using SAPs compared to IDAPs. Ten percent of participants' BrAC readings were on the descending limb 30 minutes postdrinking, and 25% were descending at 45 minutes postdrinking.


CONCLUSIONS
IDAPs result in less BrAC variability and may reduce experimental noise relative to SAPs. Experimental control in future alcohol administration studies may be enhanced by the use of IDAPs instead of SAPs.