Are needle and syringe programmes associated with a reduction in HIV transmission among people who inject drugs: a systematic review and meta-analysis

There is evidence to support the effectiveness of NSP in reducing the transmission of HIV among PWID, although it is likely that other harm reduction interventions have also contributed to the observed reduction in HIV risk. NSP should be considered as just one component of a programme of interventions to reduce both injecting risk and other types of HIV risk behaviour.