Sigma Research

The structure of sexual behaviour

Journal of Sex Research, 1992, Vol 29(1), 61-83.

Authors: APM Coxon, PM Davies, AJ Hunt, P Weatherburn, TJ McManus, CM Rees


In a National study of gay men’s sexual behaviour in the context of HIV transmission, a schema was evolved for encoding and reporting the structure of sexual activity: the Sexual Behaviour Code (SBC). It has linguistic properties, is easily learned and employed, and generalizes easily to heterosexual behaviour. Each sexual session (sentence) comprises a sequence of sexual acts (words), which in turn consists of a sexual behaviour (root), the modality (prefix), and the outcome/ ejaculation (suffix). Other aspects (partner/s, drugs, condoms) are encoded as precedents and accompaniments of the acts. The SBC is also used to define a comparable and flexible research instrument for eliciting systematic information on sexual behaviour: the Inventory of Sexual Behaviour (ISB), now used in all WHO/ GPA studies of homosexual response. Issues of validity and reliability are addressed, and forms of analysis of the resulting data are discussed for sexual diaries and inventories.


sexual behaviour, sexual diaries; sexual inventories; homosexual; HIV transmission.

Available online