Charlee Law1,2, Rhydwyn McGuire1, Mark J Ferson3,4, Su Reid1, Colleen Gately5, Jody Stephenson6, Sue Campbell-Lloyd1, Salwa Gabriel7, Tambri Housen2, Vicky Sheppeard1, Paul Corben8, David N Durrheim6,9. 1. Communicable Diseases Branch, Health Protection NSW, New South Wales. 2. National Centre of Epidemiology and Population Health, Research School of Population Health, Australian Capital Territory. 3. Public Health Unit, Planning, Population Health and Equity, South Eastern Sydney Local Health District, New South Wales. 4. School of Public Health & Community Medicine, University of New South Wales. 5. Central Coast Local Health District Public Health Unit, New South Wales. 6. Hunter New England Local Health District Public Health Unit, New South Wales. 7. Western Sydney Local Health District Public Health Unit, New South Wales. 8. Mid North Coast and Northern NSW Local Health Districts Public Health Unit, New South Wales. 9. School of Medicine and Public Health, University of Newcastle, New South Wales.
Abstract
OBJECTIVE: Vaccinations in Australia are reportable to the Australian Immunisation Register (AIR). Following major immunisation policy initiatives, the New South Wales (NSW) Public Health Network undertook an audit to estimate true immunisation coverage of NSW children at one year of age, and explore reasons associated with under-reporting. METHODS: Cross-sectional survey examining AIR immunisation records of a stratified random sample of 491 NSW children aged 12≤15 months at 30 September 2017 who were >30 days overdue for immunisation. Survey data were analysed using population weights. RESULTS: Estimated true coverage of fully vaccinated one-year-old children in NSW is 96.2% (CI:95.9-96.4), 2.1% higher than AIR reported coverage of 94.1%. Of the children reported as overdue on AIR, 34.9% (CI:30.9-38.9) were actually fully vaccinated. No significant association was found between under-reporting and socioeconomic status, rurality or reported local coverage level. Data errors in AIR uploading (at provider level) and duplicate records contributed to incorrect AIR coverage recording. CONCLUSIONS: Despite incentives to record childhood vaccinations on AIR, under-reporting continues to be an important contributor to underestimation of true coverage in NSW. Implications for public health: More reliable transmission of encounters to AIR at provider level and removal of duplicates would improve accuracy of reported coverage.
OBJECTIVE: Vaccinations in Australia are reportable to the Australian Immunisation Register (AIR). Following major immunisation policy initiatives, the New South Wales (NSW) Public Health Network undertook an audit to estimate true immunisation coverage of NSW children at one year of age, and explore reasons associated with under-reporting. METHODS: Cross-sectional survey examining AIR immunisation records of a stratified random sample of 491 NSW children aged 12≤15 months at 30 September 2017 who were >30 days overdue for immunisation. Survey data were analysed using population weights. RESULTS: Estimated true coverage of fully vaccinated one-year-old children in NSW is 96.2% (CI:95.9-96.4), 2.1% higher than AIR reported coverage of 94.1%. Of the children reported as overdue on AIR, 34.9% (CI:30.9-38.9) were actually fully vaccinated. No significant association was found between under-reporting and socioeconomic status, rurality or reported local coverage level. Data errors in AIR uploading (at provider level) and duplicate records contributed to incorrect AIR coverage recording. CONCLUSIONS: Despite incentives to record childhood vaccinations on AIR, under-reporting continues to be an important contributor to underestimation of true coverage in NSW. Implications for public health: More reliable transmission of encounters to AIR at provider level and removal of duplicates would improve accuracy of reported coverage.