How reliable are Australian Childhood Immunisation Register coverage estimates for indigenous children? An assessment of data quality and coverage.

Low levels of reporting indigenous status to the Australian Childhood Immunisation Register (ACIR) in the past have resulted in reduced confidence in vaccination coverage data for Aboriginal and Torres Straight Islander children. This study shows that the reporting of indigenous status has improved from 42% of the estimated national cohort of Indigenous children aged 12 to 14 months in 2002 to 95% in 2005. Over that period diphtheria-tetanus-pertussis (DTP) vaccination coverage estimates for Indigenous children increased slightly from 86.0% to 86.9%. Data by state and territory or remoteness are also presented. ACIR vaccination coverage estimates for Indigenous children can now be used with confidence for program planning at the national and jurisdictional level.