Study design and procedures
ALCOHOL EFFECTS, BLIND
This study was part of a larger investigation consisting of three separate randomised, double-blind, placebo-controlled, crossover trials aimed at examining the effects of alcohol (0.95 g/kg) and three commonly prescribed benzodiazepines (1 mg alprazolam, 1 mg temazepam and 5 mg diazepam) on driving performance (Australian New Zealand Clinical Trials Registry (ANZCTR, This study involved five visits to Swinburne University’s Centre for Human Psychopharmacology, with the first visit for screening and familiarisation and the following four as experimental sessions spaced at least 7 days apart. Prior to enrolment, candidates were assessed for eligibility through medical history and physical examination, and practised the cognitive assessments. On testing days, participants arrived between 9:00 a.m. and 12:00 p.m., reconfirmed their eligibility, underwent a baseline breathalyser to confirm a zero BAC and were screened for tetrahydrocannabinol, benzodiazepines, cocaine, amphetamines and opiates using a Securetec 6S DrugWipe. Participants were administered each of the following four treatments across different sessions: (1) placebo beverage plus placebo capsule; (2) 0.95 g/kg alcohol plus placebo capsule; (3) placebo beverage plus 1 mg alprazolam or (4) 0.95 g/kg alcohol plus 1 mg of alprazolam. Treatments were randomly assigned by a disinterested third party (research coordinator), and both investigators and participants were blind to the assignment. After a 30-min absorption period, participants provided BAC readings and blood samples, reported subjective drug effects using the brief biphasic alcohol effects scale (B-BAES; 