Understanding the causes of intimate partner violence is substantially more difficult than studying a disease. For example, diseases usually have a biological basis and occur within a social context, but intimate partner violence is entirely a product of its social context. Consequently, understanding the causes of such violence requires research in many social contexts. Most diseases can be investigated with various objective measures, but measurement of intimate partner violence has posed a challenge. Furthermore, measurement of social conditions thought to be risk factors, such as the status of women, gender norms, and socioeconomic status poses difficulties, especially across cultures. Although a consensus has emerged on the need to explore male and female factors and aspects of the dynamics of relationships, this has been done in very few studies. Additionally, the validity of research on sensitive topics is dependent on the context of the interview and good interviewer training. Interviewer effects can be substantial.14, 15 and 16 Researchers have only recently begun to use a multilevel approach in analyses that allows for interviewer effects.