MSM and gay refer to different things: behaviors and social identities. MSM are not limited to small, self-identified, and visible sub-populations.
The Huffington Post postulates that the term MSM was created by Cleo Manago, the man who is also credited for coining the term same gender loving (SGL). Second, its usage is tied to criticism of sexual identity terms prevalent in social construction literature which typically rejected the use of identity-based concepts across cultural and historical contexts. First, it was pursued by epidemiologists seeking behavioral categories that would offer better analytical concepts for the study of disease-risk than identity-based categories (such as 'gay', ' bisexual', or 'straight'), because a man who self-identifies as gay or bisexual is not necessarily sexually active with men, and someone who identifies as straight might be sexually active with men. in 1994 'signaled the crystallization of a new concept.' This behavioral concept comes from two distinct academic perspectives. The term MSM had been in use in public health discussions, especially in the context of HIV/AIDS, since 1990 or earlier, but the coining of the initialism by Glick et al. 5 MSM blood and tissue donor controversy.4.1.2 Other sexually transmitted infections.