Printed in U.S.A. Frequency of Sexual Partner Change in a Norwegian Population Data Distribution and Covariates

The number of new sexual partners per year (partner frequency) is a key factor in the spread of sexually transmitted diseases. Data from two Norwegian population-based surveys conducted in 1987 and 1992 were used to estimate recent (in the previous 3 years) and earlier partner frequency and to examine covariates affecting the distnbution of partner frequency. Seventy-two percent of respondents reported having no new partners per year, and 2 % reported having more than three new partners per year. Results from a Poisson regression model indicated that a low partner frequency was associated with being married or cohabrting, being female, greater age, and late sexual debut. Partner frequency was lower in 1992 than in 1987 (rate ratio = 0.8, 95 % confidence interval 0.7-0.9). In comparison with earlier life, there was a large reduction in partner frequency for married/cohabiting individuals. In contrast, there was either no change or some increase in partner frequency for single persons. Am J Epidemiol 1997; 145:636-43. sex behavior; sexual partners; sexually transmitted diseases Editor's note: A companion article by Stigum et al. appears on page 644 of this issue. The introduction of acquired immunodeficiency syndrome into our societies has led to heightene