1974: Transgender as Umbrella Term

“Transgender deviance” p 110

This does not include the genuinely girlhood- oriented boy (see p. 144 and p. 146) who is passing through the teens bound for adult transgender deviance.

“Transgender research” p 484

In some cases symptoms merge with those of transsexualism (q.v.) and the delineation between the two appears to be less clear-cut than some observers will have it. The milder case of transvestism does not come easily to medical or any other professional attention, and it has rarely been included in the reports from clinics now specializing in transgender research. Transvestism is closely related to fetishism (qv); in fact, one name recently suggested for the deviation is intermittent cross-gender dress fetishism.

Transvestites not welcome at “Transgender Center” p 487

Although in some cases transsexualism is indistinguishable from transvestism, there are some basic general differences in typical cases. The transsexual man, unlike the transvestite, obtains no erotic pleasure from wearing feminine clothing; he has always considered it his natural apparel, even though rarely permitted to wear it. When he cross-dresses it is not a masquerade or s disguise, but he perceives it as an expression of his true self (Walinder). In fact, in at least one transgender center the history of a single episode of cross-dressing in association with sexual arousal is sufficient to exclude the diagnosis of transsexualism (Baker). Unlike the transvestite he obtains no sexual pleasure though the use of his penis. His libido, as a rule, is not very pronounced, but in him masturbation fantasies and in wet dreams, if these patients’ usually unreliable reports are to be believed, he sees himself as a female.

From: Clinical sexuality: A Manual for the Physician and the Professions by John F. Oliven, 1974 

It seems clear from the context, “transgender” is used as a catch-all term which includes various types of cross-dressers, transgender research, transgender clinics and transgender centers which refer to transsexual clinics/centers.

See also: http://research.cristanwilliams.com/2011/08/15/transgender-1974-transgender-research/