National samples, sexual abuse in childhood, and adjustment in adulthood: a commentary on Najman, Dunne, Purdie, Boyle, and Coxeter (2005).

This article comments on the Najman, Dunne, Purdie, Boyle, and Coxeter (2005) study on the relationship between childhood sexual abuse (CSA) and later sexual functioning in an Australian national sample. We note the value of the Najman et al. study, being well conducted and using a generalizable sample, but critique Najman et al.'s interpretation that their study showed "significant impairment" due to the CSA. We computed effect sizes to show that the "effects" were small, and then show using meta-analysis that these small effects were consistent with results in a series of national samples from other countries. We argue that Najman et al.'s causal statement about CSA's "impairment" effect was unwarranted given their lack of causal analysis, the well-established fact in other research that CSA is often confounded with third variables, and the fact that CSA was confounded with a key third variable in Najman et al.'s study. Given the hyperbole that surrounds the issue of CSA, we emphasize the need for researchers to adhere to valid scientific principles in inference and precision when reporting the results of CSA research.