Men and women in national surveys from four countries, the United States, Canada, Great Britain, and Norway, give mutually inconsistent reports of numbers of opposite-gender sexual partners. In all cases the number of female partners reported by men exceeds the number of male partners reported by women. Gender difference in reporting bias seems to be the most plausible explanation for the discrepancies.
PIP: It is extremely difficult to collect data on sexual behavior, because this behavior is considered private and intimate, it is connected to self-image and personality, and some sexual behaviors are illegal or taboo. In addition, researchers have scant experience in collecting these data, and even less methodological research has been done on optimal collection procedures. A comparison of surveys of the number of opposite gender sex partners reported by men and women can shed light on the reliability of these data. In a closed sample, these figures should be identical, so discrepancies indicate either deviation from the closed sample or inaccurate reporting. Examination of data from 5 US surveys and 1 each from Canada, the UK, and Norway provided an opportunity to consider possible adjustments and to discern a general pattern. The pattern which emerged from this study showed that men report more female partners than women report male partners. The ratio ranged from a low of 1.16:1 to 8.45:1, with discrepancies increasing as the reference period increased. Nonresponse levels were similar for men and women, and there is little evidence that this is linked to sexual behavior. The discrepancies are reduced by truncation, but this only produces small differences which are not necessarily more valid than raw data. The ratios are decreased when adjustments made for the gender distribution of the target population include the elderly, but they increase when the elderly are excluded. The possible explanations for the discrepancies are noncoverage, nonresponse, and misreports. Analysis points to intentional misreports as the most likely culprit, with men overreporting and women underreporting. Reference periods which include a greater portion of premarital life will likely be the most distorted. Until more methodological research isolates and minimizes measurement error, any analysis should assume that either the rates reported by men or those reported by women might be correct.