Evaluation of a new diabetes screening method at the Derbarl Yerrigan Health Service

Background and objectives: Diabetes is a major health problem for the Aboriginal population of Australia. Early detection is a key strategy to reduce the burden of diabetes. The aim of this study was to assess the acceptability, sensitivity and specificity, effectiveness and cost of a new method of screening for diabetes at Derbarl Yerrigan, the Aboriginal health service in Perth. Methods: Between January and May 1999, all clients over the age of 30 years and not known to have diabetes were approached for HbA1c testing using the DCA 2000 analyser. Those whose HbA1c results indicated the need for follow-up were asked to return for confirmatory testing using the gold standard oral glucose tolerance test (OGTT). A questionnaire was administered to participants who did not return. A file audit was conducted over 15 non-consecutive days to determine screening, follow-up and the number of new cases diagnosed using the previous ad hoc approach to screening with a glucometer. Result: 238 clients were approached and all agreed to participate and undertook the test. Of these, 37 were referred for follow-up diagnostic testing. Of these, only 14 had an OGTT. Among these 14, five were found to have diabetes and three were found to have impaired glucose tolerance. Of the remaining 23 participants, we were able to contact only six and administer the questionnaire to four. Poor follow-up meant that the sensitivity, specificity and cost-effectiveness of the test could not be assessed. Conclusions and implications: The reasons for poor follow-up need to be investigated if Aboriginal health services are to be more successful at screening for diabetes.