MedDrive's Responsiveness to Alcohol
Condition: Impaired Driving
Study type: Interventional

Summary: 
      This four-way, dose-response, crossover, double blind, placebo-controlled, randomised
      validation study investigates the responsiveness of MedDrive, a computed battery of
      neuropsychological tasks, to different doses of alcohol.

      The following hypothesis are tested:

        1. Measures from MedDrive are influenced by alcohol in a dose dependent way.

        2. Effects of alcohol on driving performances are correlated to measures from MedDrive in a
           dose dependent way.

        3. Within a group of healthy young drivers, MedDrive shows consistent results over repeated
           measures (ICC≥0.7).

        4. MedDrive models effects of alcohol on driving performances better than does the UFOV or
           the trial making task.
    

Detailed description: 
      Background: There is an increasing need for physicians to advice patients on their fitness to
      drive. Current guidelines underline the limitations of existing instruments and the poor
      adaptability of batteries of neuropsychological tests assessing fitness to drive in both
      experimental and primary care settings. The investigators therefore developed MedDrive, a
      free, reliable, computer based measuring instrument capable of detecting effects of age and
      drugs on cognitive functions considered as essential for driving.

      Objectives: This study aims to test MedDrive responsiveness to different blood alcohol
      concentrations (BAC) and validate these measures against performances on a driving simulator.
      It also aims to measure MedDrive's reliability following repeated measures during the
      training phase, to compare MedDrive's performances in measuring effects of different BAC
      against the UFOV, and to model MedDrives measures to predict behaviour on the simulator.
      Finally, this study also includes a nested experimental study measuring effects of alcohol on
      attention.

      Methods: Using Widmark's formula, 16 healthy young drivers are given cranberry juice with
      different doses of ethanol to bring their BAC to 0 g/L, 0.5 g/L, 0.65 g/L, and 0.8 g/L. They
      are blinded to the presence of ethanol by inhaling vapors of ethanol just before drinking.
      BAC is maintained during the entire experiment by using a breathalyser and administrating
      drinks throughout the experiment. Three scenarios are planned on a driving simulator
      (StSoftware PvW-2010), a road tracking task, a car following task, and a car following task
      including dual tasking using peripheral vision.
    

Intervention name(s): Ethanol; Cranberry juice
Intervention type(s): Other; Other
Intervention description(s): During a 45 min period, investigators will ask participants to drink 500ml of cranberry juice, 100 ml at a time each 5 minutes. Depending of the allocation, these drinks will contain more or less alcohol. Pure ethanol will be used mixed with the beverage. The amount of alcohol to dilute in the drink will be calculated using Widmarks formula. Participants will move to the simulator room 20 minutes after having finished drinking the first 500 ml. To maintain the BAC level, investigators will use a breathalyser and provide 100 ml cranberry juice every 20 minutes with the amount of necessary alcohol. The person administrating drinks will hand over the drinks and make sure the participants breaths in before taking a sip, thereby inhaling alcohol vapour from the lid and keeping them blinded to the content.; 100 mL cranberry juice is provided in a 250 ml container.
Intervention MeSH terms: Ethanol
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Diagnostic
Keywords: impaired driving