Missed immunisation opportunities among Tongan children in Auckland, New Zealand.

AIMS

To determine the proportion of Tongan children with missed opportunities for immunisations and estimate the impact of missed opportunities on delayed immunisation.

METHODS

A retrospective audit of 133 children, conducted in two Pacific primary care clinics in Auckland. Children were eligible if born in 1999 and if the clinic was their usual source of primary care. Primary care computer data files up to December 31st 2001 were reviewed. A missed opportunity was defined as a doctor visit at which an immunisation was due but not given. An immunisation was defined as given only if the date of administration was recorded. An immunisation was delayed if not received within 30 days of first being due.

RESULTS

Seven percent of children were delayed for the six week, 67% for the three month, 72% for the five month, and 65% for the 15 month immunisations. Thirty four percent of children had at least one missed opportunity for immunisation. Most missed opportunities occurred in acute care visits, and contraindications to immunisation were almost never present. Having a missed opportunity was associated with an increased risk of delay of the six week (OR = 48.75, 95% CI 6.82, 998.16), five month (Fisher's exact test, p = 0.03) and 15 month (Fisher's exact test, p = 0.04) immunisations but not the three month immunisation (OR = 1.00, 95% CI 0.33, 3.45).

CONCLUSION

Missed opportunities are frequent and are associated with an increased risk of delayed immunisation. They are likely to contribute to New Zealand's poor immunisation coverage and the excess burden of vaccine preventable disease experienced by Pacific children in New Zealand.