Authorized in 1945, the CMB was created as a "companion" badge to the CIB with criteria for its award intended to parallel that of the CIB. It was designed to provide recognition to the field medic who accompanies the infantryman into battle
and shares with him the experiences unique to the infantry in combat. There was never any intention to award the CMB to all medical personell
who served in a combat zone or imminent danger area, that is a division level medical company supporting an infantry brigade.
As with the CIB, the infantry unit to which the medical personnel are assigned or attatched must engage the enemy in active ground combat. Since inception, the intent of the Department of the Army regarding this requirement has been that medical personell must be personally present and under fire in order to be eligible for the awarding of the badge
So stringent was this requirement during the Vietnam era that recommending officals were required to document the place (in six digit coordinates), time, type, and intensity of fire to which the proposed recipient was exposed. This fact naturally precludes the awarding of the badge to those medical personnel who accompany infantry units into a potential engagement area but do not come under enemy fire.