Unexplained and underpowered: the relationship between psychosomatic disorders and interpersonal abuse -- a critical review.

Although it is commonly accepted that interpersonal violence (IntPV) leads to adverse health consequences, the available data are far from decisive. To test the hypothesized link, the authors devised an evidence-based strategy to determine the data quality in studies purporting to link IntPV and some medically unexplained disorders in women (irritable bowel syndrome, chronic pelvic pain, fibromyalgia/chronic fatigue, and other chronic pain syndromes). English language studies with control groups of unaffected women were assessed for the quality of their methodologies. The number of studies, together with the consistency of their findings in each domain, was collated to determine the overall weight of evidence regarding the link for each condition. The quantity and quality of research in each clinical area proved to be sparse. In general, most research was limited to small, convenience samples, with insufficient attention to the design of control groups and to sample size. The evidence currently available regarding irritable bowel syndrome, fibromyalgia/chronic fatigue, chronic pelvic pain, and other chronic pain syndromes does not allow for any firm conclusion regarding their link to IntPV. More research - paying particular regard to the methodological concerns identified here - is required in order to generate any definitive conclusions.