An effort to take a closer look at data on same-sex couples has found that between one quarter and three quarters of gays, lesbians, and bisexuals are victims of domestic violence. That compares to the Justice Department and CDC figures of about 22 percent of women and about 7 percent of men in society as a whole. The numbers came by combing the findings of four studies using the data of nearly 30,000 gay participants. “I think taken together it seems pretty clear that the true prevalence may be higher for same-sex couples,” said Richard Carroll, one of the co-authors. The reasons for the higher rate, the authors believe, could be the stress of being a sexual minority, internalized homophobia, prior exposure to domestic violence, and drug use.