Related Experiment Video
Updated: Mar 9, 2026

The Motivation for Alcohol Reward: Predictors of Progressive-Ratio Intravenous Alcohol Self-Administration in Humans
Published on: April 28, 2022
Passengers at risk: a multi-level analysis of the decision to travel with a drunk driver
José Ignacio Nazif-Muñoz1, Aharon Blank-Gomel2
1McGill University, Institute of Health and Social Policy, Montreal, Quebec, Canada.
Aims:
To assess the impact of demographic, intrapersonal and environmental factors on the likelihood in Chile of becoming a passenger of an alcohol-impaired driver (PAID).
Design:
Multi-level cross-sectional study.
Setting:
Data were acquired from two large-scale household surveys of representative samples of Chile's Metropolitan Region.
Participants:
The study included 1341 individuals ≥ 16 years; 696 of them reported engaging in PAID.
Measurement:
The primary outcome was self-reported frequencies of having accepted a ride with an alcohol-impaired driver.
Findings:
PAID was associated significantly with 'age' [odds ratio (OR) = 0.99, 95% confidence interval (CI) = 0.98-0.99, P = 0.03], 'traffic safety beliefs' (OR = 0.17, 95% CI = 0.078-0.44, P = 0.00), 'time exposure as passenger' (OR = 1.00, 95% CI = 1.00-1.01, P = 0.00) and 'sex' (OR = 0.67, 95% CI = 0.53-0.87, P = 0.00). In women, PAID was associated with 'age' (OR = 0.98, 95% CI = 0.97-0.99, P = 0.02), 'traffic safety beliefs' (OR = 0.17, 95% CI = 0.05-0.59, P = 0.00) and 'low quality of public bus stops' (OR = 0.97, 95% CI = 0.98-0.99, P = 0.01). Younger women with high education levels were more likely to engage in PAID than younger women with low education levels. In men, PAID was associated with 'traffic safety beliefs' (OR = 0.13, 95% CI = 0.02-0.63, P = 0.01) and 'time exposure as passenger' (OR = 1.00, 95% CI = 1.00-1.01, P = 0.02).
Conclusions:
In Chile, men are at higher risk of becoming a passenger of an alcohol-impaired driver (PAID) than women. In women, PAID appears to be associated with lower traffic safety beliefs, lower quality of public bus stations and an interaction between education and age. In men, PAID is associated with lower traffic safety beliefs and higher time exposure as passenger.
Related Concept Videos
Hypothesis Test for Test of Independence
H0: The two variables (factors)...
Relative Risk
Drug Toxicity: Risk factors
Introduction to Test of Independence
The test statistic for a test of independence is similar to that of a goodness-of-fit test:
Determination of Expected Frequency
Hazard Ratio
For example, in a clinical trial...

