Similar proportions of males and females reported teaching someone to inject ever (38% vs 37%) and in the preceding 12 months (16% vs 19%). There was also no significant difference in terms of ethnicity or mean age of those who had ever taught someone to inject ever or in the preceding 12 months. Those who had taught someone else to inject heroin had been injecting for a greater mean number of years than the remainder of the sample (13 v. 10 years; t = -3.08, df = 370, p = 0.002). However, this difference diminished for those who had recently (preceding 12 months) taught someone to inject (11 years for both groups).
