The Frequency of High-Risk Behaviors Among Iranian College Students Using Indirect Methods: Network Scale-Up and Crosswise Model

Since the direct questions usually underestimate the frequency of sensitive behaviors, indirect methods can be used to estimate the frequency of some risky behaviors such as illicit drug use, sexual behaviors especially where these behaviors are highly stigmatized. In the current study, we indirectly estimated the prevalence of some risky behaviors among college students using two indirect methods: network scale-up (NSU) and crosswise model (CM). Having recruited 563 students from one of Iran’s major medical universities, the prevalence of opium and drug use, alcohol consumption, relationships with the opposite sex (RWOS),and extra/pre-marital sex (EPMS) were estimated using two indirect methods. The estimated prevalence using the CM and NSU were alcohol consumption (16.8% vs. 8.1%), opium use (2.2% both), methamphetamine use (7.2% vs. 1.2%), taking tramadol without medical indications (14.8% vs. 4.8%), RWOS (42.3% vs. 31.9%), and EPMS (12.4% vs. 7.1%). Lower estimations in the NSU method might be due to the transmission barrier, which means that students were not fully aware of the high-risk behaviors of their close friends. Nonetheless, it seems that these risky behaviors were more or less common among Iranian college students.