People who preload alcohol before a night out drink more than they predict and are more intoxicated at the end of the night a Griffith University study has found.

Researchers surveyed and breath-tested (BrAC) 360 patrons as they entered Night Time Entertainment Districts (NEDs) in Brisbane. Of these,143 returned and completed an exit BrAC and questionnaire.

Lead researcher Professor Grant Devilly from the School of Applied Psychology said they wanted to examine people’s motivation for alcohol preloading, their estimation for drinking during the night and the impact that preloading has on how inebriated people become across the night.

“We found that people were motivated to preload to save money and socialise, were likely to drink more than they predicted over the course of the night and were more surprised by their blood alcohol reading (BrAC) the higher it was,’’ Professor Devilly said.

“We also found there was little difference between men and women. For men, extroversion contributed to the likelihood of drinking more while for women body mass index significantly contributed to increased inebriation.

“We found that people had higher BrACs on exit compared to entry, but the level were only small to moderate. The higher the BrAC of patrons at entry, the less time they spent in the city. People were also surprised by their BrAC reading the higher it was on entry.

Professor Devilly said the research results held implications for future interventions related to alcohol consumption in NEDs including public policy, policing practices and individual interventions.

“There is a need to target drinking behaviours at point of contact rather than simply basing interventions on time of night. If motivations are to be addressed, these must be unique to preloading or drinking while in NEDs.

“If the aim of these interventions is to reduce intoxication levels of individuals leaving NEDs, preloading must be addressed given the magnitude of its predictive power. Getting people into town earlier and less drunk is the first step.

“Additionally, interventions aimed at assisting people to track their consumption may be helpful. From this research it seems those who drink to go out, carry on drinking once they are out.”

The study “Drinking to go out or going out to drink?” is published in the Journal of Drug and Alcohol Dependence.