"Full time? You're not talking about replacing real doctors?"
"No, no, of course not. Why is everyone so worried about holograms taking over the universe?"
The Long-term Medical Holographic program (LMH) was a holoprogram developed by Doctor Lewis Zimmerman in mid-2373, at the behest of Starfleet, for use as a fully-fledged medical officer. Intended for situations where a holo-doctor would be more beneficial than a humanoid, such as on research outposts, subspace communication stations, and long-range exploratory vessels; anywhere that life support or living space was at a premium and where the primary mission does not require the doctor to leave sickbay. This project aimed to extend the usability of Zimmerman's previous work, the Emergency Medical Holographic program.
In designing the LMH, Zimmerman concluded that it would be necessary for the holo-doctor to interact naturally with patients for weeks at a time. In doing so, he felt it necessary for the holo-doctor to be "expected to share amusing anecdotes, extend sympathy, swap dirty jokes, and even have culinary opinions formed by experience."
The LMH test program 1 was initially created as a basic shell sporting Bashir's template with its responses and database taken from a standard EMH Mark I. To further enhance the LMH program, Zimmerman intended to conduct in-depth interviews with Bashir's family, friends, and colleagues in order to build a more rounded psychological profile.
Bashir was later deemed unsuitable as a template due to evidence that he had undergone illegal genetic enhancements, and Zimmerman departed DS9 before the project was complete. (DS9: "Doctor Bashir, I Presume")
By the following year, and with the LMH program evidently sidelined, Zimmerman's EMH Mark II was put in service, notably aboard the experimental prototype USS Prometheus, a vessel "designed for deep space tactical assignments," critera shared with the LMH, and thus began the eventual replacement of the "inferior" Mark I. (VOY: "Message in a Bottle")