Mark-recapture estimation of the local prevalence of problem drinking: An account of the results of a feasibility study

Mark-Recapture methods of prevalence estimation have been widely used to estimate the local prevalence of injecting drug use, based on the ethical identification and modelling of overlaps between different partial agency populations of drug injectors. Re-application of this technique to estimation of local prevalences of problem drinking has been frustrated by the fact that different local agencies are likely to have different operational definitions of their target problem drinking populations. A feasibility study was conducted to explore the possibility of producing local problem drinking estimates by combining mark-recapture modelling with the use of AUDIT, a screening instrument. Unfortunately, low rates of screening by agencies produced very few overlaps, but after modification to the research design it proved possible to estimate the prevalence of problem drinking as 8.6 % of the local population (95 % CI: 6.0 % to 12.8 %). It is recommended that this approach to population estimation be used for problem drinking populations only where screening of agencies' clients/patients can be centrally directed and resourced and conducted by trained interview teams.