A visual inspection protocol for measuring characteristics of used syringes

This article reports on the use of a Visual Inspection Protocol (VIP) to measure observable characteristics of syringes deposited at the San Francisco needle exchange program. Syringes received by the program were evaluated by several inspectors using the VIP, and interrater reliability was assessed for each item. In Study I, syringes bearing individual markings made by the user (n = 568) were more likely to be capped at the point end and plunger end, and more often were new in appearance when compared with unmarked syringes (n = 2,820). In Study II, syringes with a short street life (n = 250) were more often new in appearance and were less likely to contain blood than syringes with a long street life (n = 246). Syringes having individual markings also show signs of more careful use, and marking syringes may represent an ad hoc HIV prevention strategy for some injection drug users.