A new campaign has been launched to determine how much of a threat drug rape poses.
No reliable figures on drug assisted rape have ever been released
Nine specialist rape centres in England and Wales are conducting the first ever official research into the problem.
Senior police officers have expressed concerns that there are no genuine statistics on drug assisted rape.
For the study, in cases where a victim alleges or police officers suspect drugs have played a part, screening for a range of chemicals will take place.
Derbyshire CID's Detective Chief Superintendent Dave Gee, who is spearheading the initiative called Operation Matise, said: "There is a lack of valid data around which actually shows the prevalence of this kind of offence.
"What we are trying to do is put together some empirical data which will actually tell us the depth of concern around this type of offence."
The Roofie organisation, which was set up to help victims of drug rape, says it has received around 6,000 calls from women and men since 1997.
Newspapers have carried campaigns about the subject and even offered free testing kits so that drinks can be monitored during a night out.
But Mr Gee warned: "To my knowledge, and having consulted the Forensic Science Service on this, there is no single definitive test which can identify specific drugs in drinks or bodily fluids. It is a far more complicated issue than many people realise.
"There are one or two products on the market which say that they can do this, but also in the small print say that they cannot do this.
"I wouldn't like people to be buying these kits, using them in public places and feeling that they are safe, because that may not be the case."
A campaign warning of the dangers of leaving drinks unattended was also recently launched by Staffordshire Police.
But while there have been proven cases of spiked drinks being used to subdue victims, no reliable figures have ever been released.
As a result, the latest research is expected to produce the first ever official statistics on the subject by next spring.
Operation Matise will begin in August or September, subject to
approval from ethics watchdogs.
The following forces will help collate data: the Metropolitan Police, Greater Manchester, Lancashire, West Midlands, Northumbria, Leicestershire and Derbyshire.