Health services research in oral health care: an empirical example.

Health services research is mainly applied research which can contribute to the production of knowledge necessary to appropriate decisions in health care. As an example, a study of the occurrence of tooth extractions is presented. Two hypotheses were tested: a negative relationship between provider density and consumer income, and the probability of tooth extractions and the number of teeth extracted, conditional upon extraction. A nationwide sample of 1286 non-institutionalized Norwegians 20 yr and above was interviewed by a public survey institute. The data were analyzed using a two-part model including logistic regression and multiple regression analysis. One third of the sample had had a tooth extraction during the last 5 yr. The majority of the sample had few teeth extracted at the time of extraction. The probability of tooth extraction was related to provider density and not to consumer income. The number of teeth extracted was related neither to provider density nor to income. Tooth extraction was not related to age. Some policy implications are discussed.