RESUMO
To describe patterns of diagnostic testing during the antenatal period and to assess the potential benefit of using Medicare claims data in monitoring testing practice, we examined the matched claims data (with identifying details removed) on approximately 10,000 women having a confinement for which a Medicare benefit was claimed between 1 July and 30 September 1990. The results showed that almost all the women included in the study sample had an ultrasound and blood group and antibody examination. A smaller proportion had serological tests for syphilis (77 per cent), rubella (51 per cent) and hepatitis B carriage (73 per cent). Two-thirds had urine microscopy and culture, and under half (40 per cent) had serum alpha-fetoprotein estimation. Few (18 per cent) had a claim processed for microscopy and culture of a genital swab and fewer than 8 per cent claimed for any other pathology tests. There were differences in the proportions having tests, depending on whether the clinician managing the confinement was a specialist obstetrician or a general practitioner, and depending on geographic area and age group. While the data do not represent all women having a confinement in New South Wales, the selective use of antenatal diagnostic tests found in this study is of considerable public health importance and analysis of claims data can provide useful information for health professionals.