[Vaccination coverage in local and national perspective. Vaccination coverage before and after introduction of a local computerized system in the municipality of Sandefjord].

The author presents the results from an examination in Sandefjord three years before and four years after implementation of a computer-based information system in 1986. The targets for immunization rates are well defined, but the methods for monitoring and calculation of the rates are not satisfactory. The rates seem to be reliable when given for the whole country. The fallacies caused by denominator problems when the rates are calculated for municipalities are discussed. An analysis of immunization rates and reasons for incomplete vaccination in the case of children born during the period 1983 to 1989 has been carried out in Sandefjord, an urban municipality with approximately 36,000 inhabitants. The average immunization coverage against diphtheria, tetanus, polio, whooping cough, measles, mumps and rubella (for children aged 2-5 years) showed record levels, i.e. about 97-98% of children for the whole period. The predominant reason for incomplete vaccination was that the parents did not want their child to be exposed to vaccination. In the case of a very few children the vaccination programme was delayed by medical contradictions.