Frequencies and percentages were calculated for all patients who were diagnosed with an AUD by their GP or by CIDI (at least a mild AUD as per DSM-5), had not received treatment, and had a valid answer in the questions concerning treatment seeking. Exploratory logistic regressions were calculated to investigate patient characteristics (age, sex, years of education, employment status, and AUDs severity) predictive of providing a valid answer in the questions concerning treatment seeking. Percentages and frequencies of broader categories by country were calculated for the past 12 months. To investigate country specific outliers, standardized residuals [35] were calculated. A standardized residual > |3| was considered as outlier [35]. The country specific results are reported in the Additional file 1: Table S3 and should be interpreted with caution, because of the small sample size.
