There are two unique contributions of this study towards examining the measurement of CSA. The first is that we conducted a significance test of non-nested models to determine which measure was most worthwhile in terms of explaining the contribution of CSA to negative sexual experiences and revictimization. We determined that both the short and long summed composites of CSA explained a similar percentage of variance as a binary measure assessing a history of exposure to CSA (presence or absence). However, the significance tests identified both summed composites as a better fit to the data offering more explanatory power than the binary measure. These results differ from those reported by Godbout et al., (2009)
, which concluded that the presence of CSA, regardless of its severity, was a risk factor for adult interpersonal difficulties. Further, whereas the analyses conducted by Godbout were limited to comparing the statistical fit between models, including R square, our evaluation of the explanatory power through hypothesis tests revealed statistically significant differences between models. When we only compared fit statistics, including R square and PRESS, the binary measure and summed composites explained similar amounts of variation. However, the hypothesis test for non-nested models provided overwhelming evidence in favor of the summed composite over solely assessing the presence of CSA. The main advantage of the Cox Likelihood Ratio tests is that it allowed us to statistically compare model performance under different CSA measures and offer information beyond model fit indexes as to which CSA measure was the best with respect to generating the outcome.
The second contribution of this study is that we checked whether our results could be replicated by cross-validating the predictive power of each CSA composite score. We confirmed moderately consistent CSA regression estimates within training and validation samples for both summed composites and we demonstrated that using fitted values from the training sample produced predictions on the outcome in the validation sample that were similar to actual observed values. These findings suggest that the predictive ability observed in our study between CSA severity and lifetime sexual risks and revictimization could be replicated in other settings.
It is important to note that the summed composites of CSA (both short and long) reflect women’s cumulative histories. This stands in contrast to studies which restrict their examination of CSA to the first incident (Glover et al., 2010
) or the type of incident, for instance, the most intrusive or abuse involving penetration (Godbout et al., 2009
). It is not always clear which incident is the subject of focus in other studies. For women who report more than one abuse incident, the characteristics of these incidents are likely to differ. The summed composite utilized here takes these differences into account and more accurately reflects the cumulative burden, or severity, of CSA experiences before age 18. Despite this benefit, the summed composite assumes that discrete CSA incidents are additive, which may not reflect the actual impact of these experiences and continues to be a challenge for the field.
The characteristics included in our summed composite are thought to represent distinct, but shared aspects of CSA experiences. In this sample of CSA victims and non-victims, the individual dimensions correlated with the outcome in a similar manner as the CSA severity indices. However, methodological considerations for subsequent studies are that the four dimensions were highly interrelated and susceptible to multicollinearity when included as independent variables in a regression analysis. To address this issue, individual dimensions should be deleted or combined into a meaningful construct, for example, the CSA severity composite used in this study. When we restricted our sample to CSA survivors only, moderate to high correlations among the individual dimensions persisted. However, when we examined only the worst type of abuse incident, rather than considering all incidents of CSA cumulatively, the correlations between CSA dimensions were drastically reduced, and were consistent with those obtained by prior research (Godbout et al., 2009
). We hypothesize that multicollinearity would hinder subsequent analysis if each dimension were left as independent variables and we were able to demonstrate inconsistent negative associations between age of onset of abuse, perpetrator of abuse, and lifetime health risks and revictimization. In the future, research utilizing different dimensions of CSA must address the issue of multicollinearity, as each of these characteristics is measuring a distinct aspect of CSA.
A limitation of the current study is the use of retrospective, unsubstantiated self-report of child sexual abuse experiences, although this data is commonly used in CSA research. Second, the prevalence rate of approximately 33 percent obtained in this study is consistent with typical national estimates of CSA prevalence among females (Senn, et al., 2006
). The women in this study also reported experiencing very severe CSA characteristics, somewhat in contrast to other community samples (Godbout et al., 2009
; Kallstrom-Fuqua, Weston, & Marshall, 2004
). At least half of the women experienced penetration and identified a family member as the perpetrator. In contrast, only 15 percent of Godbout et al. (2009)
sample reported penetrative CSA and approximately one-fourth of the women in another community sample reported abuse by a father figure (Kallstrom-Fuqua et al., 2004
). This may be due, in part, to the nature of the questions used to assess CSA. Whereas some studies (Godbout et al., 2009
) ask respondents to endorse whether or not they were sexually abused, the questions used in this study did not require participants to label their experiences as abusive. Rather, participants were asked whether or not they had experienced one of nine behaviorally oriented screening questions. Child sexual abuse questions were also administered face-to-face in a private interview room, as one component of a larger questionnaire, which allowed for rapport to be established and may have led participants to feel more comfortable revealing and discussing CSA incidents (Senn et al., 2006
). It is likely that asking the questions utilized in this study outside of the context of the larger interview would decrease the comfort level of patients in a clinical setting and result in a lower prevalence rate. Further, although research is identifying intervening variables that moderate the CSA - negative outcomes relationship, this study examined only direct associations between CSA severity and negative sexual experience and outcomes. We were also unable to control for or examine the contributions of other types of child maltreatment or negative experiences to negative sexual experiences and outcomes (Glover et al., 2010
), potentially limiting our understanding of other potential risk factors.
Another limitation was the inability to examine more aspects of CSA experiences, including use of force and duration of CSA incidents, characteristics commonly used to describe CSA (West et al., 2000
; Beitman et al., 1992; Weaver, Chard, Mechanic, & Etzel, 2004
). As such, our summed composite does not reflect the degree to which CSA incidents involved coercion or force per se. Similarly, our outcome did not comprehensively measure sexuality per se, but was constructed using a limited number of sexual risk measures, including adult sexual revictimization, unintended pregnancy, sexually transmitted diseases including HIV, number of sexual partners since1980, and age of first consensual sex. As such, the number of sexual partners variable used in this study did not represent lifetime number of sexual partners for all participants in the study due to differences in current age of participants. The selection of these measures was driven by prior research linking CSA to these outcomes. An exploratory factor analysis (results not shown) suggested that these measures could represent a unified construct of negative sexual experiences and revictimization. Further, combining these sexual experiences into a single dependent variable builds upon prior literature that found independent associations between CSA, number of sexual partners, and coercive revictimization (Merrill et al., 2003
; Fortier et al., 2009
). We demonstrate that CSA severity not only significantly relates to but better explains the variance in negative sexual experiences and revictimization. It is worth noting that approximately five percent of the sample reported age of first consensual sex before age 12; these women were deleted from the analyses, as they were developmentally unable to truly consent to intercourse at such a young age. Due to the cross-sectional nature of this data, we are also faced with a temporal limitation, as we were unable to be certain that some measures included in the outcome (i.e., number of sexual partners, sexually transmitted infections, and unintended pregnancies) occurred after the CSA incident(s) occurred (Elze et al., 2001).
The superiority of the CSA summed composites over the binary variable in this study is limited to associations with negative sexual experiences and outcomes. The application of these measures often will depend on the type of inference to be gained. The utility of a binary measure of CSA may be adequate when research is focused on calculating prevalence rates, but the field is increasingly focusing on measuring the severity of experiences in relation to negative outcomes for which CSA survivors are thought to be vulnerable. In this context, the use of a binary CSA variable is inherently limited, because it can only capture whether or not abuse occurred at any point in childhood, and cannot capture any characteristics of a single CSA incident or more than one CSA incident that occurs over time. However, results of this study and Godbout et al., (2009)
do suggest that the presence of CSA itself is a risk factor for later negative sexual experiences and outcomes.
The severity of CSA, rather than its occurrence, is more useful in making clinical decisions that impact a child’s life (Slep & Heyman, 2004
) and the qualitative and quantitative differences between CSA experiences have been hypothesized to explain variations in outcomes (DiLillo, 2001
). As performed within this study, future research should assess the explanatory power and calibrate the predictive ability of summed composites that reflect cumulative histories of CSA with regard to other psychological and physical outcomes. This may allow researchers and clinicians to more fully understand the vulnerabilities that CSA survivors with different experiences may face and could eventually lead to consistent universal guidelines for defining CSA severity in relation to a broad range of outcomes. This includes defining which characteristics of abuse are most important aspects to consider in relation to CSA severity. At a minimum, the four characteristics of the summed composite comprising CSA severity should be considered in clinical settings when working therapeutically with women at risk for or reporting negative sexual experiences and outcomes. In addition, clinicians may be well advised to ask about whether or not force was a factor in CSA incidents. The questions used in this study to capture CSA, though designed by researchers, can be readily used by clinicians in everyday practice. Despite their sensitive nature, they are not difficult nor time consuming to administer, qualities promoted by researchers in the field (Slep & Heyman, 2004
). However, despite its clinical utility, we caution against the idea of categorizing CSA histories (i.e., mild, moderate, and severe), as clinical cut-points have yet to be empirically determined and await future research. Although other indexes that capture multiple forms of maltreatment have been designed to produce such categories, we feel that they are somewhat arbitrary for both research and clinical purposes, as they do not take into account a host of variables other than CSA that may be important. Furthermore, prior research has shown the difficulty with identifying ideal clinical cut-points to define appropriate categories (Altman, Lausen, Sauerbrei, & Schumacher, 1994
; Austin & Brunner, 2004
; Cohen, 1983
). Clinical decisions and treatment implications are more likely to hinge on a variety of background and current experiences and characteristics in addition to the severity of CSA experiences. Nonetheless, understanding where CSA victims fall on a continuum of CSA experiences may be helpful in designing treatment options for these women.