Long-term follow-up of schizophrenia in 16 countries

An unexpected finding of the International Pilot Study of Schizophrenia, launched by the World Health Organization (WHO) in 1967, was that patients in countries outside Europe and the United States have a more favourable short- and medium-term course of the disease than those seen in developed countries. Since then, WHO has intensified its schizophrenia research programme and has initiated a set of international studies that have confirmed these initial findings and explored possible reasons for such differences in the course and outcome of schizophrenia. While such work has provided important findings and has generated additional pertinent hypotheses, it did not explain the differences in outcome. The present paper describes a new initiative in which approximately 2500 subjects involved in previous WHO multicentre schizophrenia studies are being followed up for between 15 and 25 years after initial examination. Nineteen research centres in 16 countries are taking part in this work. The research methodology is described.On behalf of the collaborating investigatorsThis paper is based on the data and experience obtained during the participation of the authors in the International Study on Schizophrenia (ISoS), a project sponsored by the World Health Organization, and funded by the World Health Organization, the Laureate Foundation (Untied States of America) and the participating centres.The chief collaborating investigators in the 19 field research centres and one methodological support centre of this study are: Aarhus: A. Bertelsen; Agra: K.C. Dube; Beijing: Shen Yucun; Cali: C. Leon; Chandigarh: V. Varma; Dublin: D. Walsh; Groningen: R. Giel; Hong Kong: P. Lee; Honolulu: A.J. Marsella; Ibadan: M. Olatawura; Khartoum: T. Baasher; Madras: R. Thara; Mannheim: H. Häfner; Moscow: S.J. Tsirkin; Nagasaki: Y. Nakane; Nottingham: G. Harrison; Orangeburg: E. Laska; Prague: S. Skoda; Rochester: L. Wynne; Sofia: K. Ganev. At WHO Headquarters, Geneva, the study has been coordinated by N. Sartorius (until August 1993), by W. Gulbinat (September 1993–April 1996) and Dr. Janca (since May 1996).