Conditional versus unconditional risk estimates in models of aids-related risk behaviour

Abstract
This study focuses on the concept of perceived risk and its relations to behavioural intentions and behaviour. Most research on health related behaviour employs a measure of unconditional risk. Given the inconsistent findings concerning the relationship between perceived risk and behavioural measures in the health literature, we investigated the usefulness of a conditional risk estimate as an alternative measure. In total, 247 heterosexual visitors of a STD-clinic participated in this study. Hundred participants had private partners only, 147 engaged in prostitution contacts. The relationship between the unconditional measure of perceived risk and behavioural intentions was found to be dependent upon sample-differences. However, it appeared that when a conditional risk estimate was used, a significant positive relation with intention was observed, regardless of the risk-status of the sample. Given the results of the present study, and the closer resemblance of the conditional risk measure to the original concept of vulnerability or susceptibility, it is argued that a conditional risk measure is more useful than a relatively general, unconditional measure of perceived risk.