Longitudinal inconsistency in responses to survey items that ask women about intimate partner violence

Longitudinal research has demonstrated that experiences of abuse and adversity are not consistently reported over time; however, there is a paucity of available evidence regarding the consistency of reporting experiences of intimate partner violence (IPV) over time. This study aimed to investigate the consistency of self-reported IPV involving a partner or spouse. Differences in the health status of women according to consistency of IPV reporting was also investigated.

Survey data collected from the 1946-51 cohort of the Australian Longitudinal Study on Women's Health (ALSWH) between 1996 and 2016 were used (n = 13,715). Consistency of self-reported IPV was evaluated by responses to the question "Have you ever been in a violent relationship with a partner/spouse?" Demographic and health characteristics of consistent and inconsistent reporters of IPV were compared. Multinomial logistic regression was used to determine the strength of the association between demographic and health characteristics of the women and their consistency of longitudinal reporting of IPV.

There were 10,966 women who answered IPV questions over six surveys, with 9610 women (87.6%) providing consistent responses. Inconsistent responses were provided by 1356 women (12.4%), of whom 258 (2.4%) reported IPV at all but one survey (Mainly IPV), 587 (5.3%) reported no IPV at all but one survey (Mainly no IPV), and 511 (4.7%) reported Mixed IPV responses over time. Women in the Mainly IPV group, and those in the Mixed IPV group were similar to those in the Consistent IPV group in demographic and health characteristics, whereas women in the Mainly no IPV group were similar to those in the Consistent never IPV group.

IPV data collected at one time point may involve around 12% false negative or false positive responses. To increase reliability, IPV should be measured on more than one occasion, using different techniques and methods that account for intentional and unintentional over- and under-reporting.