Analytical approach:
The analysis was based on a decision-tree model with a 30-year time horizon. The authors stated that a societal perspective was adopted.
Effectiveness data:
: The efficacy of the programme, which was the key clinical input of the model, was from a questionnaire administered to a sample of 1,234 individuals out of 1,480 tested in Stockholm during the programme implementation in 2007. The efficacy of the programme was the proportion of individuals who reported that they would not have had a test without the Chlamydia Monday programme. The chlamydia prevalence was from the 1,480 individuals tested. The rates of sequelae were from selected published studies.
Monetary benefit and utility valuations:
The utility values were from published data on health-related quality of life and they were derived using the Health Utilities Index (HUI) Mark II.
Measure of benefit:
Quality-adjusted life-years (QALYs) were the benefit measure and they were discounted at an annual rate of 3%.
Cost data:
The economic analysis included the costs of the advertising campaign, project administration and activities in health centres, staff time, urine test, treatment with doxycycline for positive individuals, productivity losses, sequelae of unidentified chlamydia cases (in-patient and out-patient costs), and screening and treatment of partners found by contact tracing. Some information on resource consumption was given, with most of the data being derived from published sources. The costs of the advertising campaign were from the accounts of the Stockholm County Council. Personnel costs were based on data from the Swedish Association of Health Professionals. Productivity losses were derived from average income statistics and the treatment costs were from local hospitals. All costs were in Swedish kronor and converted into Euros (EUR). They were discounted at an annual rate of 3% and the price year was 2007.
Analysis of uncertainty:
A series of one-way sensitivity analyses was undertaken to test how robust the results were to variations in the efficacy of the programme, the risk of pelvic inflammatory disease, the prevention of future production loss, the disease prevalence, the exclusion of contact tracing, and the length of chronic conditions. The alternative ranges of values were based on authors’ opinions.