Fig. 2.
Pooled odds ratio (OR) and 95% confidence interval (CI) of short sleep duration (< 7 h) according to the risk of alcohol-related problems. The OR and the 95% CI of each country were obtained through logistic regression models adjusted by age (years, continuous), sex (female, male), body mass index (Kg/m2, continuous), tobacco consumption (yes, no), free-time physical activity (lower, higher level), and self-rated health (optimal, suboptimal). The colored diamonds indicate the odds ratios for each study, and their respective 95% CIs are indicated by adjacent horizontal lines (Brazil, green; Chile, blue; Spain, red). The transparent diamonds indicate the pooled OR (center of the diamonds) and the 95% CI (width of the diamonds) calculated for the association between the intermediate risk and the high risk subgroup categories of alcohol consumption, as well as for the set of both categories (overall) and short sleep duration. The vertical black line indicates OR = 1, that is, the value at which the relationship between alcohol and sleep would be zero. When the 95% CI crosses this line, the association tested is not statistically significant (p > 0.05). The weight column indicates the proportion of each study and category considered for the calculation of the overall polled OR and is determined according to the number of participants and cases with short sleep duration analyzed in each country