New research suggests the use of high-potency marijuana may be linked to an increased risk of psychosis, Medical News Today reports. The study was conducted by researchers at the institute of Psychiatry, Psychology and Neuroscience at King's College London in the UK. Dr. Marta Di Forti and her team observed the effects of high-potency marijuana use among 780 individuals aged 18-65. Between 2005 and 2011, 410 participants reported a first episode of psychosis, according to the article. Psychosis occurs when people experience hallucinations or delusions, often happening in conjunction with particular mental health disorders, such as schizophrenia, bipolar disorder and depression. The research suggests, according to Dr. Di Forti, that the risk of psychosis among marijuana users is dependent on different factors, like frequency of use and drug potency - factors which should be considered by physicians. "When a GP or psychiatrist asks if a patient uses cannabis it's not helpful; it's like asking whether someone drinks," says Dr. Di Forti. "As with alcohol, the relevant questions are how often and what type of cannabis. This gives more information about whether the user is at risk of mental health problems; awareness needs to increase for this to happen." It was determined that around 24% of psychosis cases could be avoided if people were to stop using this high-potency cannabis, the article reports. Although, since the study was conducted over a long period of time, the researchers say they did not have data on how much marijuana was used each day, which could present problems. "However, because we collected information about use over a period of years and not about present use, the reliability of such detailed information would probably have been confounded by recall bias to a greater extent than was the general description of pattern of use that we obtained," the researchers add. The findings were published in The Lancet Psychiatry.