A closure assembly for a medical device, preferably in the form of a tamper evident closure, having an outer sleeve including an open end and a closed end. A tip cap includes a flow restrictor disposed within the sleeve in accessible relation by the medical device through the open end. An indicator member is removably connected to the tip cap within the sleeve and a retainer member is connected to an interior of the sleeve in an interruptive, disconnecting relation to the indicator member by a snap-fit connection. The indicator member is captured within said hollow interior upon removal of said tip cap from the sleeve through the open end. An end cap may be attached to the sleeve, to define a closed end thereof, by a snap-fit connection similar to, but distinguishable from, the snap-fit connection between the retainer member and the interior of the sleeve.