This article reports the initial results of a prospective study on the prevalence of psychiatric disorders in the Dutch population aged 18-64. The objectives and the design of the study are described elsewhere in this issue. A total of 7076 people were interviewed in person in 1996. The presence of the following disorders was determined by means of the CIDI: mood disorders, anxiety disorders, eating disorders, schizophrenia and other non-affective psychoses, and substance use disorders. Psychiatric disorders were found to be quite common. Some 41.2% of the adult population under 65 had experienced at least one DSM-III-R disorder in their lifetime, among them 23.3% within the preceding year. No gender differences were found in overall morbidity. Depression, anxiety, and alcohol abuse and dependence were most prevalent, and there was a high degree of comorbidity between them. The prevalence rate encountered for schizophrenia was lower (0.4% lifetime) than generally presumed. A comparison with findings from other countries is made. Relevant determinants of psychiatric morbidity were analysed.

The article describes the objectives and design of a prospective study of the prevalence, incidence and course of psychiatric disorders in a representative sample of non-institutionalized Dutch adults. A total of 7146 men and women aged 18-64, contacted through a multistage sample of municipalities and households, were interviewed at home in 1996. The primary diagnostic instrument was the CIDI, which determines the lifetime occurrence of DSM-III-R disorders. The disorders included were: mood disorders, anxiety disorders, eating disorders, schizophrenia and other non-affective psychotic disorders, and dependence and abuse of psychoactive substances. Follow-up measurements in the same sample were scheduled at 12 and 36 months. The net response to the first measurement was 69.7%. Poststratification weightings were applied for gender, age, marital status and degree of urbanization. Limitations and advantages of the study design are discussed. Findings are reported elsewhere in this issue.

To assess the prevalence and effects of alcohol and drug use in heterosexual and homosexual commercial contacts, and the relationship between their use and unsafe sexual behaviour, 127 female prostitutes, 27 male prostitutes, 91 clients of female prostitutes and 24 clients of male prostitutes were interviewed face-to-face with the help of a semi-structured questionnaire. The respondents were living or working in different parts of The Netherlands. Alcohol and drug use was found to be relatively common among prostitutes. This was also so for the use of alcohol by clients, though to a lesser extent. Prostitutes' consumption varied widely according to the type of prostitution they were employed in. Those meeting their clients in clubs or bars reported the highest consumption of alcohol; hard drugs were used predominantly by street prostitutes. It appears that the main effects of alcohol and drug use are on how the individual experiences working as, or calling on, a prostitute, the social interaction between the two parties, and the sexual contact itself. The common assumption that drinking alcohol has negative effects on condom use was not borne out; though female prostitutes working under the influence of drugs were significantly more likely to report unsafe sex. The degree to which commercial partners were judged to be under the influence of alcohol or drugs was not found to bear upon the frequency of respondents' condom use. For those prostitutes who use hard drugs, this use plays an important role in their engaging in unsafe sexual activities. Prevention activities should focus especially on this group, and should take into account the role of such drug use.

No abstract