Costing substance misuse services

To develop a methodology for obtaining the detailed costs of different substance misuse services and illustrate some of the specific problems by means of a case study.

Data on the resources required, clinical activity, and patient characteristics for one year were combined to provide detailed costs for different types of clinical events and patients.

The clinical services of a publicly funded addiction unit in a large industrial city in the UK. The unit provides for alcohol and other drug misusers mainly on an outpatient basis but with inpatient care.

Over 1500 patients were included in the analysis with 75 per cent being male, and 80 per cent aged between 20 and 49. Nearly half of the clients had alcohol as their main drug of misuse with opiate users being the next largest group.

Detailed costing by event and patient was possible as the staff type and time taken for each event were routinely recorded. A cost for each individual event was estimated and summed for each individual patient to give a cost estimate by patient for the financial year 1992/3.

Core treatment outpatient events had an average cost of Pounds 48, with new assessments costing Pounds 87 but these averages hid high variations. The average cost per year for those receiving only outpatient care was Pounds 358; it was Pounds 1857 for those receiving both outpatient and inpatient care. Opiate misusers were on average more costly than alcohol misusers. The costs were skewed with 10 per cent of patients accounting for 56 per cent of the total annual costs.

Dealing with costs of non attendance, including all resource use, and coping with large individual variations in costs across individuals and intervention types are the main problems in devising cost figures. Cost data are useful but need to be combined with outcome data if they are to be used to improve patient services.