Two criticisms of Bem’s theory in the journal "Psychological Review" concluded that "studies cited by Bem and additional research show that Exotic Becomes Erotic theory is not supported by scientific evidence." Bem was criticized for relying on a non-random sample of gay men from the 1970's (rather than collecting new data) and for drawing conclusions that appear to contradict the original data. An "examination of the original data showed virtually all respondents were familiar with children of both sexes", and that only 9% of gay men said that "none or only a few" of their friends were male, and most gay men (74%) reported having "an especially close friend of the same sex" during grade school. Further, "71% of gay men reported feeling different from other boys, but so did 38% of heterosexual men. The difference for gay men is larger, but still indicates that feeling different from same-sex peers was common for heterosexual men." Bem also acknowledged that gay men were more likely to have older brothers (the fraternal birth order effect), which appeared to contradict an unfamiliarity with males. Bem cited cross-cultural studies which also "appear to contradict the EBE theory assertion", such as the Sambia tribe in Papua New Guinea, which ritually enforced homosexual acts among teenagers, yet once these boys reached adulthood, only a small proportion of men continued to engage in homosexual behaviour - similar to levels observed in the United States. Additionally, Bem's model could be interpreted as implying that if one could change a child's behavior, one could change their sexual orientation, but most psychologists doubt this would be possible.