Between 1988 and 2000 93 women were convicted of sexual offences in Sweden. Researchers at Karolinska University compared the incidence of mental illness and substance abuse in this group with 20,000 randomly selected women in the normal population and 13,000 women convicted of non-sexual crimes in the same period. 37% of the female sex offenders had undergone treatment in a psychiatric clinic and 8% had been diagnosed with psychosis but there was no difference in the incidences of mental illness and drug abuse between these women and women who had committed other kinds of violent crime. However, the figures differed widely from the control group of normal women with the rates of psychosis being 16 times higher and that of drug abuse being 23 times higher.
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