2019-20 Irish National Drug and Alcohol Survey

The survey used stratified and multistage area probability sampling methods to select a representative sample of the Irish population that was aged 15 years and older and was living in private households. The primary sampling frame was An Post/Ordnance Survey Ireland’s GeoDirectory, a complete database of every building in the Republic of Ireland. Each of the 2.2 million addresses contained in GeoDirectory includes an accurate standardised postal address, usage details for each building (commercial or residential), a unique 8-digit identity number, Eircode, and geo-coordinates which accurately locate the centre point of each building to within one metre. The sample needed to sufficiently large and structured to provide national estimates of drug use prevalence and estimates for RDATF area. It was calculated that 650 completed interviews in each of the 10 RDATF areas would be required. A three-stage process was used to construct the sample for this survey. Stratification techniques were used to select primary sampling units (PSUs). In this survey, electoral divisions (EDs) were defined as PSUs. In this survey, EDs were defined as PSUs. In the first stage of stratification, the number of addresses for each RDATF was agreed at between 980 and 1,344. In the second stage of stratification, 421 PSUs were randomly selected. These PSUs were then ranked by sociodemographic indicators (degree of urban/rural respondents and proportion of owner occupiers) to ensure that a representati **Purpose:** The National Drug and Alcohol Survey (NDAS) collects information on alcohol and tobacco consumption and drug use among the general population in Ireland. It also surveys people’s attitudes and perceptions relating to tobacco, alcohol, and other drug use and records the impact of drug use on people’s communities. The 2019–20 NDAS collected information from 5,762 people aged 15 years and older across Ireland. Out of scope: health status, treatment interventions, prescribed medications apart from **Coverage:** Prevalence estimates are calculated at a national level and for the 10 Regional Drug and Alcohol Taskforce (RDATF) areas at a later stage. Data collection start February 2019. Data collection finish March 2020.