How many children are fully immunised?

An attempt was made to find the number of confirmed immunisations received by a group of Whangarei four-year-olds. The claims made for the immunisation benefit by each child's general practitioner were compared with questionnaire responses given by the parents of the children. Of 135 parents, 91.1% claimed that their child had received all four early childhood immunisations. Corresponding claims for the immunisation benefit by the child's general practitioner for all four immunisations were found in only 34.9% of cases. There was 79.7% agreement between parental reports and general practitioners' claims for the three-month immunisation. Corresponding figures were 72.3%, 67.2% and 66.4% for the five-, twelve- and eighteen-month immunisations respectively. These findings suggest that many children miss one or two immunisations rather than a few missing most. Present methods of monitoring may therefore tend to over-estimate the level of full immunisation. Computerisation of immunisation data is proposed as an alternative.