One thing I have noticed over the years of studying drug use and drug counselling is the bias towards males. In any statistics you come across whether they be rates of use, rates of ODs, rates of viral infections invariably males will be higher. Not always but in the vast majority of cases males will be at the higher rates.
For example see these charts of illicit drug use in Australia. These are typical of the statistics one comes across over and over in terms of gender bias.
I have always wondered why this would be so.
Why should males very consistently be the ones to use more and use more dangerously and so on?