1 Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI.
2 Gender and Health Group, Medical Research Council of South Africa, Pretoria, Gauteng, South Africa.
3 Reproductive Health Research Unit, University of the Witswatersrand, Johannesburg, Gauteng, South Africa.
4 School of Social Work, University of Michigan, Ann Arbor, MI.
5 Perinatal HIV Research Unit, University of the Witwatersrand, Johannesburg, Gauteng, South Africa.
Received for publication May 1, 2003; accepted for publication February 5, 2004.
![]() |
ABSTRACT |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
child abuse, sexual; domestic violence; prevalence; rape; risk; South Africa; violence; women
Abbreviations: Abbreviations: HIV, human immunodeficiency virus; SADHS, South African Demographic and Health Survey; WHO, World Health Organization.
![]() |
INTRODUCTION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Experience of violence in childhood, particularly sexual violence, has been identified as a risk factor for experiencing violence in adulthood, a phenomenon known as "revictimization" (68). However, most research on revictimization has been carried out in developed countries, with a disproportionate number of studies carried out among American college students (6, 7). These studies have consistently found correlations between child sexual assault and adult sexual (916) and physical (15, 1722) assault, but comparison of results across studies remains difficult because of widely varying definitions of violence (68). In particular, comparatively little work has distinguished sexual assaults by male partners from sexual assaults by other men. Research from geographically diverse settings has shown that sexual violence by male partners frequently occurs in conjunction with other abusive behaviors, including physical and emotional abuse (2325), and thus often functions as part of an overall pattern of control and exploitation within an ongoing sexual relationship (17, 26). This suggests that it may be more appropriate to view physical and sexual violence perpetrated by intimate partners as different manifestations of a single phenomenon, with sexual violence perpetrated by nonpartners considered separately.
Age cutpoints used to distinguish between child and adult experiences of violence have ranged from 13 years to 18 years of age (6), leading to ambiguity regarding whether violence in teenage years should be considered as exposure or outcome when assessing revictimization. One recent meta-analysis of revictimization literature found no independent effect for the choice of age cutoff on the magnitude of associations between child sexual assault and adult victimization (6). Studies from the United States that examined child, adolescent, and adult sexual violence separately have suggested that adolescent victimization may be more strongly associated with adult revictimization than sexual assault in childhood (8, 11, 12), highlighting the potential importance of violent experiences associated with the onset of sexual activity. Recent studies from developing countries further suggest that sexual violence at first intercourse may increase womens risk of later adverse reproductive health outcomes, including teenage pregnancy (27) and human immunodeficiency virus (HIV) (28).
In this paper, we draw on data from women who attended antenatal clinics in Soweto, South Africa, to explore the following questions: What is the prevalence of different types of gender-based violence in the population and what are the patterns of joint occurrence? What is the age at onset of violence and how does this compare with age at first intercourse? Finally, how does child sexual assault or forced first intercourse affect womens risk for experiencing intimate partner violence or sexual assault by nonpartners later in life?
![]() |
MATERIALS AND METHODS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Women arrived at the clinics early each weekday morning, and the patient queue was established prior to commencement of voluntary counseling for HIV. The number of women seeking care at each clinic on a given day ranged from zero to over 50. A team of six South African female fieldworkers trained in gender-based violence and HIV/acquired immunodeficiency syndrome awareness visited the clinics in a systematic rotation and screened women who had received HIV pretest counseling for possible participation in the study. When patient volume in a clinic was low (generally 12 patients or less), all patients were screened for eligibility as they completed voluntary counseling for HIV; when patient volume was higher, we used the established clinic queues to systematically sample women for eligibility screening.
Consent documents and questionnaires were developed in English and translated into isiZulu and Sesotho in collaboration with the fieldwork team to ensure appropriate use of local dialect. Informed consent procedures and interviews were conducted in private and completed prior to the participants receiving results of her HIV test. Interviews used structured questionnaires and covered sociodemographic characteristics, gender-based violence, sexual behavior, relationship with male partner, substance use, and reproductive history. Participants were offered referral information for local support services specializing in violence against women and HIV/acquired immunodeficiency syndrome. All procedures followed World Health Organization (WHO) ethical and safety recommendations for research on domestic violence against women (29). Ethical approval was obtained from the University of the Witswatersrand, Johannesburg, South Africa, and the University of Michigan, Ann Arbor, Michigan.
Our final sampling frame comprised 3,982 pregnant women who attended study clinics during the fieldwork period. Of these women, 1,790 (45.0 percent) were sampled and screened for potential eligibility, and 1,467 (82.0 percent) of those were eligible. Of the 323 ineligible women, 274 declined or delayed HIV testing (84.8 percent), 21 did not have a language in common with the interviewer (6.5 percent), 11 had prior knowledge of HIV-positive status (3.4 percent), 11 had previously received care at another research site (3.4 percent), and six were under the age of 16 years (1.9 percent). Of the potentially eligible women, 1,395 (95.1 percent) agreed to participate.
Intimate partner violence
We assessed male intimate partner violence using a modified version of the WHO violence against women instrument; this measure was developed for and validated in a seven-country prevalence study (30). It contains four questions on emotional violence from male partners, six questions on physical violence, and three questions on sexual violence. To increase local relevance, we added three questions on financial abuse and four questions on emotional abuse, all of which had been identified as important in previous South African studies of partner violence (27, 31); details of final questions are provided in tabular material below. This instrument elicited information on the past year and lifetime history of financial, emotional, physical, and sexual abuse by male intimate partners, including the frequency of specific behaviors and the age at first occurrence of physical or sexual assault by an intimate partner.
Other sexual violence
We chose age 15 years as the cutpoint between child and adult experience of sexual violence to facilitate comparability of our data with the data of the WHO Multi-Country Study (30) and the South African Demographic and Health Survey (SADHS) (32). Questions on sexual violence were adapted for this study from similar questions in the WHO study (30), the SADHS (32), and a population-based study of violence in three South African provinces (31, 33). Sexual assault before the age of 15 years was assessed using one question on unwanted touching and one on unwanted sex (32, 33). Questions also assessed the age at first occurrence and frequency of assaults. Women were also classified as experiencing child sexual assault if they reported sexual intimate partner violence (n = 7) or forced first intercourse (n = 62) prior to the age of 15 years. Adult sexual assault by nonpartners was assessed using two questions on sexual assault by men other than boyfriends or husbands at age 15 or more years. Again, questions included information on the age at first occurrence and frequency of assaults. These questions are given in tabular material below.
To assess experiences at first intercourse, we asked women to choose the statement that most accurately described their experience of first coitus: "I was willing," "I was persuaded," "I was tricked," "I was forced," or "I was raped." Women who reported being forced or raped were considered to have experienced forced first intercourse (prevalence values including women who reported being tricked were also calculated to allow comparison). Women were also considered to have experienced forced first intercourse if they reported forced sex by a male intimate partner, or rape by a nonpartner, before the reported age of first intercourse. In these cases (n = 42), the age at first forced sex was considered to represent the age at first intercourse.
Statistical analysis
Data were double entered into Epi Info version 6.04d public domain software available from the Centers for Disease Control and Prevention, Atlanta, Georgia, and then transferred to SAS version 8.02 software (SAS Institute, Inc., Cary, North Carolina) for analysis. After examining descriptive statistics, we calculated cumulative incidence functions to describe the age at first intercourse, the age at first occurrence of physical or sexual violence by a male partner, and the age at first occurrence of adult sexual assault by a nonpartner. As the prevalence of violence is high in this population, we considered it likely that women who had not yet experienced physical/sexual partner violence or adult sexual assault by a nonpartner might experience these events later in life (34). Thus, women who did not report these outcomes were censored at their age as of the date of the interview. The SAS PROC LIFETEST (SAS Institute, Inc.) (Kaplan-Meier method) was used to estimate the survivor function for each variable, and this function was then inverted to yield the cumulative incidence function.
To evaluate whether child sexual assault or forced first intercourse influenced the risk of later physical/sexual partner violence or adult sexual assault by a nonpartner, we constructed separate Cox hazard models for each of these outcomes, in each case treating child sexual assault and forced first intercourse as time-varying covariates. Chronologic age at the incidence of the first violent event was used as the time axis for both models; women who had not experienced the violent outcome under consideration were censored at their age at interview. In cases where the age at first intercourse and the age at first physical/sexual partner violence were equal, we assumed first intercourse to have preceded partner violence. In modeling adult sexual assault by nonpartners, however, we set the time-varying predictor variable to take the value of 1 only when the age at sexual assault was greater than the age at first intercourse. This accounted for the possibility that first intercourse and first adult sexual assault by a nonpartner might comprise a single event.
![]() |
RESULTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
|
|
|
|
![]() |
DISCUSSION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Prevalence of gender-based violence
We chose to treat physical and sexual violence by male intimate partners as a single construct, with sexual assaults by nonpartners considered separately. Classifying violent experience by perpetrator is consistent with ethnographic research on perceptions of violence by South African women, who generally identify sexual violence by husbands and boyfriends to be part of an overall pattern of male control in intimate relationships and as a phenomenon distinct from rape and sexual violence by other men (26, 35). The extensive overlap between different manifestations of intimate partner violence and the fact that physical and sexual assaults are more likely to be repeated when financial and/or emotional abuse occurs simultaneously confirm that partner assaults are most often part of a broader pattern of controlling behavior.
The prevalences of all types of violence reported in this study are generally comparable with or higher than estimates from prior population-based studies. The SADHS (32) and the Three Province Study (36, 37) reported lifetime estimates of physical violence from intimate partners ranging from 12.5 percent to 26.8 percent, compared with 50.4 percent in this study. We conjecture that the higher lifetime prevalence of intimate partner violence found in our study may reflect higher disclosure facilitated by an interview environment away from the womans home and the use of a more detailed instrument than previously utilized (38, 39). The SADHS and the Three Province Study estimated prevalences of lifetime rape plus attempted rape ranging from 3 percent to 12 percent, which is comparable to our result of 8 percent.
In the SADHS, 1.6 percent of women nationwide reported having been raped before the age of 15 years (40), compared with 5.0 percent in our study that used an identical question. The overall prevalence of child sexual assault in our study (8.0 percent) is thus higher than population-based data would suggest, although lower than other South African research that used much broader definitions. A study in the Northern Province included unwanted kissing and found that 54.2 percent of 414 school students reported unwanted sexual contact, although only 13.3 percent of these considered themselves to have been abused (41, 42). Researchers and study participants often differ in their understandings of what constitutes report-worthy violence. Despite our use of questions focused on specifically described behaviors, the prevalence of child sexual abuse in this study may reflect selective underreporting by women. Focus groups in the Eastern Cape with adolescent women who had been asked similar questions revealed that, because severe sexual harassment and rape were so common, young women reported to interviewers only those incidents of unwanted sexual touching that they judged to be "serious" (Mzikazi Nduna, Medical Research Council, personal communication, 2003).
First intercourse: age and use of force
No population-based study in South Africa has examined forced first intercourse, but other local studies have reported prevalences ranging from 10.0 percent (43) to 28 percent (44), although the latter value is an overestimate as virgins were dropped from the denominator. Our finding that 12.4 percent of women were forced at first intercourse, with 7.3 percent forced at the age of 15 or more years, is thus consistent with other data, as is our finding that age at first coitus for women is inversely related to the probability of consent (43, 4549). Future research on age and consent at first intercourse would benefit from use of right-censored, age-dependent methods that can correctly account for the presence of participants who have not experienced coitarche.
Age at onset of adult violence
The age of onset of intimate partner violence has received scant attention to date (25, 34, 50). We found that the incidence of physical and/or sexual partner violence rose sharply at the age of 15 years and remained relatively constant through the late thirties, with cumulative incidence estimated to be 30.5 percent by age 30 years. A study of 211 Japanese-American women in Los Angeles found that the risk of first partner physical violence was highest from the ages of 1822 years and declined thereafter (34). Among women reporting physical/sexual partner violence in our study, approximately 60 percent reported onset either before (2.1 percent), concurrent with (11.7 percent), or within 5 years of first coitus (45 percent). A study of 188 women in Nicaragua found that, among married or cohabiting women who had experienced violence, 50 percent reported that it began within 2 years of marriage or cohabitation, while 80 percent reported that it began within 4 years (25). Taken together, these results suggest that the period surrounding sexual debut and the early years of a new relationship may be high-risk times for onset of partner assault. The relatively constant incidence shown in our sample might be explained by the facts that few participants were married and that 62.3 percent were in relationships of less than 4 years duration. The distribution of relationships is consistent with population-based data from the SADHS (32), suggesting that the age-at-onset findings here are likely to be broadly generalizable to South African women. Further research incorporating cross-cultural comparisons of risk factors associated with onset of partner revictimization violence will help to clarify this issue.
Revictimization
We found that child sexual assault was associated with increased risk of both physical/sexual partner violence and adult sexual assault by nonpartners; this result is consistent with prior research showing associations between child sexual assault and adult violence in developed countries (921, 51, 52). Forced first intercourse similarly increased the risk of reporting both forms of violence, although the association was only marginally significant for later events of adult sexual assault by nonpartners. Taken together, these results suggest that forced first intercourse after the age of 15 years has a similar impact on the risk of revictimization as does childhood sexual assault, and these results support the hypothesis that having an early sexual experience that is unwanted, regardless of age, contributes to increased risk of later revictimization. We also found that these early unwanted sexual experiences were associated with younger age at onset of adult violence. This finding is consistent with preliminary results from population-based research in Japan using the same WHO instrument (Mieko Yoshihama, University of Michigan, personal communication, 2003) and suggests the need for proactive secondary prevention efforts with young survivors of violence. It also highlights the utility of survival analysis on retrospectively collected data on age at first violence.
Limitations
This study has some limitations. We have no data available on clinic attendees who were not sampled for screening, and thus we cannot determine how well the women sampled represent the overall clinical population. The cross-sectional design required us to rely on womens ability to recall violent experiences, as well as the age at which they first occurred, and on participants willingness to disclose this information (53, 54). It is likely that violence, despite the high observed prevalence, is underreported and that data on age at onset are somewhat imprecise. Prior research in South Africa has shown that forced first intercourse is associated with increased risk of pregnancy under the age of 18 years (27), and violence has been noted as a risk factor for pregnancy in several other settings (2). It is therefore possible that survivors of violence are overrepresented in our study population, but there is no reason to believe that the interrelations between different forms of violence and patterns of onset should be different from those of the general population. All of the women in our sample, by virtue of their pregnancy, were known to have experienced unprotected coitus and thus may not be representative of women who are not sexually active or use successful contraception. Likewise, study participants in their thirties may not be representative of South African women of this age. Overall, however, participants are likely to be representative of pregnant South African women, as 92 percent of these women use public facilities for antenatal care (55).
Conclusions and directions for future research
This study confirms that gender-based violence is a key health risk among South African women. The finding that 21.8 percent of women seeking antenatal care experienced multiple assaults by a male partner in the last 12 months strongly suggests that violence during pregnancy is sufficiently common to warrant development of violence-related interventions for antenatal care in South Africa. Our findings also provide evidence that primary and secondary prevention of gender-based violence is urgently needed among South African adolescents. Further research is needed to clarify the mechanisms through which early assaults leave women vulnerable to revictimization and to develop appropriate strategies for secondary prevention. Preventing gender-based violence in South Africa may be particularly urgent given the associations demonstrated elsewhere between experience of gender-based violence and womens HIV serostatus (56). Cross-cultural comparisons of patterns on the age at onset of violence will help to elucidate risk factors for incidence and also help to create much needed prevention and intervention programs.
![]() |
ACKNOWLEDGMENTS |
---|
The authors thank the field team for their extraordinary efforts, the counselors and nursing sisters in the study clinics for facilitating the work, and the staff of the Perinatal HIV Research Unit and the Gender and Health Group for their support.
![]() |
NOTES |
---|
![]() |
REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|