Credit: NSW Government A comprehensive analysis of 80 scientific studies has identified a 'window of impairment' of between three and 10 hours caused by moderate to high doses of the intoxicating component of cannabis, tetrahydrocannabinol (THC). The findings have implications for the application of drug-driving laws globally, researchers say. The study found the exact duration of impairment depends on the dose of THC, whether the THC is inhaled or taken orally, whether the cannabis user is regular or occasional and the demands of the task being undertaken while intoxicated. The study represents the first such meta-analysis and distilled the results of 80 separate scientific studies into THC-induced impairment conducted over the past 20 years. It has been published in