Aside from being heterosexual or homosexual, individuals can be any of varying degrees of bisexual. Bailey "et al." stated that they expect that in all cultures the vast majority of people are sexually predisposed exclusively to the other sex, with a minority being sexually predisposed to the same sex, whether exclusively or not. In Western surveys, about 93% of men identify as completely heterosexual, 4% as mostly heterosexual, 0.5% as more evenly bisexual, 0.5% as mostly homosexual, and 2% as completely homosexual. An analysis of 67 studies found that the lifetime prevalence of sex between men (regardless of orientation) was 3–5% for East Asia, 6–12% for South and South East Asia, 6–15% for Eastern Europe, and 6–20% for Latin America. The World Health Organization estimates a worldwide prevalence of men who have sex with men between 3 and 16%.