The use of couple data to determine the reliability of self-reported sexual behavior

Unreliable self-reporting of sexual behavior has been suggested as a major cause of variance in survey research. In addition, differing gender-related biases are thought to account for discrepancies in reports of oral and anal sex. Insufficient attention, however, has been given to assessing the reliability of the sexual partner's reports. Data obtained from 70 couples concerning 68 sexual behaviors was reviewed. Four different reliability indices yielded moderate to substantial agreement. These included a simple percentage criterion of 87%, a Kappa of .67, and conditional probabilities of .77 and.91. Previously reported discrepancies in the reporting of oral and anal sex were not found. Kappa was found to be superior to simple percentage agreement, but produced overly conservative reliability estimates when derived from behaviors that occur at either high or low base-rates. The two conditional probability indices are proposed for use in conjunction with Kappa to evaluate the reliability of partner data.