What's in a mean? - An examination of the inconsistency between men and women in reporting sexual partnerships

The mean rate of partner change is a key variable used in mathematical models of the transmission dynamics of sexually transmitted diseases and human immunodeficiency virus. This paper uses data from the British National Survey of Sexual Attitudes and Lifestyles to explore the consistency of responses given by men and women to questions about sexual Life style. In common with other surveys of this nature, men report a higher mean number of heterosexual partners than do women. Possible explanations for such a finding are given in this paper and we show that the discrepancies can be reduced by making certain assumptions. The importance of the age mixing of sexual partnerships is highlighted.