Survey collected the experiences of 15,500 drug users during a four week period between November and December
The Guardian/Mixmag survey attempts to provide a detailed snapshot of the real attitudes and experiences of a broad range of drug users, examining the way people consume a wide range of illicit and legal substances, from alcohol and cannabis to cocaine and MDMA as well as newer drugs such as mephedrone and synthetic cannabis.
Building on the established Mixmag drug surveys - which have run since 1999 and last year polled 2,500 clubbers' over drug use - this year's survey collected the experiences of 15,500 drug users worldwide during a four week period between November and December 2011.
The survey was promoted online by the Guardian and Mixmag and via social media. Half the respondents were from the UK, a further 4,000 from the US and Canada, the remainder from a range of mainly European or English-speaking countries
Conducted by Global Drug Survey a self-funding, independent drug use data exchange, the anonymous online survey asked a range of detailed questions about respondents gender, background, status, the drugs they use, how much they pay for them, drug quality and harms, and the health and legal consequences of their use on them and their friends.
You can read more about Global Drug Survey's research methods here.
Just over two thirds of the UK respondents were male. Just over 90% of the UK respondents classed themselves as white; just under 5% said they were either black, Asian, Asian British or mixed. Of the UK respondents 82% described themselves as heterosexual; 5% classed themselves as gay, and 8% bisexual. The rest preferred not to say.
The bulk of UK respondents were aged between 16 and 50: the mean age was 28. Almost three quarters said they were in work. 55% had a degree or higher degree, and a third were living with their partner.
Some classed themselves as clubbers - having been clubbing at least once in the last month, others did not. You can read Mixmag's 2012 drug survey - which focuses on clubbers' experiences - here.
The survey was designed by Dr Adam Winstock, a consultant addictions psychiatrist in London, and director of Global Drug Survey. It received ethics approval from the joint Institute of Psychiatry and Maudsley trust ethics committee. Global Drug Survey does not receive government funding.
• You can find out more about the The Global Drug Survey drugsmeter - an internet-based tool (and soon a phone app) - which enables drug users to compare their drug use against that of other people who drink and take drugs here.