A study of 156 victims of child sexual abuse found that the majority of the children came from disrupted or single-parent homes; only 31 percent of the children lived with both biological parents. Although stepfamilies make up only about 10 percent of all families, 27 percent of the abused children lived with either a stepfather or the mother's boyfriend. Source: Beverly Gomes-Schwartz, Jonathan Horowitz, and Albert P. Cardarelli, "Child Sexual Abuse Victims and Their Treatment", U.S. Department of Justice, Office of Juvenile Justce and Delinquency Prevention. Researchers in Michigan determined that "49 percent of all child abuse cases are committed by single mothers." Source: Joan Ditson and Sharon Shay, "A Study of Child Abuse in Lansing , Michigan ", Child Abuse and Neglect, 8 (1984). "A family structure index -- a composite index based on the annual rate of children involved in divorce and the percentage of families with children present that are female-headed -- is a strong predictor of suicide among young adult and adolescent white males." Source: Patricia L. McCall and Kenneth C. Land, "Trends in White Male Adolescent, Young-Adult and Elderly Suicide: Are There Common Underlying Structural Factors?" Social Science Research 23, 1994. " Fatherless children are at dramatically greater risk of suicide." Source: U.S. Department of Health and Human Services, National Center for Health Statistics, Survey on Child Health, Washington , DC , 1993. In a study of 146 adolescent friends of 26 adolescent suicide victims, teens living in single-parent families are not only more likely to commit suicide but also more likely to suffer from psychological disorders, when compared to teens living in intact families. Source: David A. Brent, et al. "Post-traumatic Stress Disorder in Peers of Adolescent Suicide Victims: Predisposing Factors and Phenomenology.", Journal of the American Academy of Child and Adolescent Psychiatry 34, 1995. "Boys who grow up in father-absent homes are more likely that those in father- present homes to have trouble establishing appropriate sex roles and gender identity." Source: P.L. Adams, J.R. Milner, and N.A. Schrepf, "Fatherless Children", New York , Wiley Press, 1984. "In 1988, a study of preschool children admitted to New Orleans hospitals as psychiatric patients over a 34-month period found that nearly 80 percent came from fatherless homes." Source: Jack Block, et al. "Parental Functioning and the Home Environment in Families of Divorce", Journal of the American Academy of Child and Adolescent Psychiatry, 27 (1988) "Children living with a never-married mother are more likely to have been treated for emotional problems." Source: L. Remez, "Children Who Don't Live with Both Parents Face Behavioral Problems," Family Planning Perspectives (January/February 1992). Children reared by a divorced or never-married mother are less cooperative and score lower on tests of intelligence than children reared in intact families. Statistical analysis of the behavior and intelligence of these children revealed "significant detrimental effects " of living in a female-headed household. Growing up in a female-headed household remained a statistical predictor of behavior problems even after adjusting for differences in family income.