After more than 12 years of development, the ninth edition of the Present State Examination (PSE-9) was published, together with associated instruments and computer algorithm, in 1974. The system has now been expanded, in the framework of the World Health Organization/Alcohol, Drug Abuse, and Mental Health Administration Joint Project on Standardization of Diagnosis and Classification, and is being tested with the aim of developing a comprehensive procedure for clinical examination that is also capable of generating many of the categories of the International Classification of Diseases, 10th edition, and the Diagnostic and Statistical Manual of Mental Disorders, revised third edition. The new system is known as SCAN (Schedules for Clinical Assessment in Neuropsychiatry). It includes the 10th edition of the PSE as one of its core schedules, preliminary tests of which have suggested that reliability is similar to that of PSE-9. SCAN is being field tested in 20 centers in 11 countries. A final version is expected to be available in January 1990.

https://jamanetwork.com/journals/PSYCH/articlepdf/495050/archpsyc_47_6_012.pdf

SCAN. Schedules for Clinical Assessment in Neuropsychiatry.

• The Composite International Diagnostic Interview (CIDI), written at the request of the World Health Organization/US Alcohol, Drug Abuse, and Mental Health Administration Task Force on Psychiatric Assessment Instruments, combines questions from the Diagnostic Interview Schedule with questions designed to elicit Present State Examination items. It is fully structured to allow administration by lay interviewers and scoring of diagnoses by computer. A special Substance Abuse Module covers tobacco, alcohol, and other drug abuse in considerable detail, allowing the assessment of the quality and severity of dependence and its course. This article describes the design and development of the CIDI and the current field testing of a slightly reduced "core" version. The field test is being conducted in 19 centers around the world to assess the interviews' reliability and its acceptability to clinicians and the general populace in different cultures and to provide data on which to base revisions that may be found necessary. In addition, questions to assess International Classification of Diseases , ninth revision, and the revised DSM-III diagnoses are being written. If all goes well, the CIDI will allow investigators reliably to assess mental disorders according to the most widely accepted nomenclatures in many different populations and cultures.

https://jamanetwork.com/journals/PSYCH/articlepdf/494437/archpsyc_45_12_003.pdf

The Composite International Diagnostic Interview: An Epidemiologic Instrument Suitable for Use in Conjunction With Different Diagnostic Systems and in Different Cultures

Background Understanding the prevalence of schizophrenia has important implications for both health service planning and risk factor epidemiology. The aims of this review are to systematically identify and collate studies describing the prevalence of schizophrenia, to summarize the findings of these studies, and to explore selected factors that may influence prevalence estimates. Methods and Findings Studies with original data related to the prevalence of schizophrenia (published 1965–2002) were identified via searching electronic databases, reviewing citations, and writing to authors. These studies were divided into ‘‘core’’ studies, ‘‘migrant’’ studies, and studies based on ‘‘other special groups.’’ Between- and within-study filters were applied in order to identify discrete prevalence estimates. Cumulative plots of prevalence estimates were made and the distributions described when the underlying estimates were sorted according to prevalence type (point, period, lifetime, and lifetime morbid risk). Based on combined prevalence estimates, the influence of selected key variables was examined (sex, urbanicity, migrant status, country economic index, and study quality). A total of 1,721 prevalence estimates from 188 studies were identified. These estimates were drawn from 46 countries, and were based on an estimated 154,140 potentially overlapping prevalent cases. We identified 132 core studies, 15 migrant studies, and 41 studies based on other special groups. The median values per 1,000 persons (10%–90% quantiles) for the distributions for point, period, lifetime, and lifetime morbid risk were 4.6 (1.9–10.0), 3.3 (1.3– 8.2), 4.0 (1.6–12.1), and 7.2 (3.1–27.1), respectively. Based on combined prevalence estimates, we found no significant difference (a) between males and females, or (b) between urban, rural, and mixed sites. The prevalence of schizophrenia in migrants was higher compared to nativeborn individuals: the migrant-to-native-born ratio median (10%–90% quantile) was 1.8 (0.9–6.4). When sites were grouped by economic status, prevalence estimates from ‘‘least developed’’ countries were significantly lower than those from both ‘‘emerging’’ and ‘‘developed’’ sites (p = 0.04). Studies that scored higher on a quality score had significantly higher prevalence estimates ( p= 0.02).

https://espace.library.uq.edu.au/view/UQ:75868/UQ_PV_75868.pdf

A systematic review of the prevalence of schizophrenia.

Phasic versus tonic dopamine release and the modulation of dopamine system responsivity: a hypothesis for the etiology of schizophrenia

Recent systematic reviews have encouraged the psychiatric research community to reevaluate the contours of schizophrenia epidemiology. This paper provides a concise overview of three related systematic reviews on the incidence, prevalence, and mortality associated with schizophrenia. The reviews shared key methodological features regarding search strategies, analysis of the distribution of the frequency estimates, and exploration of the influence of key variables (sex, migrant status, urbanicity, secular trend, economic status, and latitude). Contrary to previous interpretations, the incidence of schizophrenia shows prominent variation between sites. The median incidence of schizophrenia was 15.2/100,000 persons, and the central 80% of estimates varied over a fivefold range (7.7-43.0/100,000). The rate ratio for males:females was 1.4:1. Prevalence estimates also show prominent variation. The median lifetime morbid risk for schizophrenia was 7.2/1,000 persons. On the basis of the standardized mortality ratio, people with schizophrenia have a two- to threefold increased risk of dying (median standardized mortality ratio = 2.6 for all-cause mortality), and this differential gap in mortality has increased over recent decades. Compared with native-born individuals, migrants have an increased incidence and prevalence of schizophrenia. Exposures related to urbanicity, economic status, and latitude are also associated with various frequency measures. In conclusion, the epidemiology of schizophrenia is characterized by prominent variability and gradients that can help guide future research.

/pdf/schizophrenia-a-concise-overview-of-incidence-prevalence-and-17oihtj6hz.pdf

Schizophrenia: A Concise Overview of Incidence, Prevalence, and Mortality

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/4C45DDB6CAB367EB9A2DD91E4FEF13C9/S0264180100000904a.pdf/div-class-title-schizophrenia-manifestations-incidence-and-course-in-different-cultures-a-world-health-organization-ten-country-study-div.pdf

Schizophrenia: manifestations, incidence and course in different cultures. A World Health Organization ten-country study.

In a context of a WHO collaborative study, 12 research centres in 10 countries monitored geographically defined populations over 2 years to identify individuals making a first-in-lifetime contact with any type of 'helping agency' because of symptoms of psychotic illness. A total of 1379 persons who met specified inclusion criteria for schizophrenia and other related non-affective disorders were examined extensively, using standardized instruments, on entry into the study and on two consecutive follow-ups at annual intervals. Patients in different cultures, meeting the ICD and CATEGO criteria for schizophrenia, were remarkably similar in their symptom profiles and 49% of them presented the central schizophrenic conditions as defined by CATEGO class S+. However, the 2-year pattern of course was considerably more favourable in patients in developing countries compared with patients in developed countries, and the difference could not be fully explained by the higher frequency of acute onsets among the former. Age- and sex-specific incidence rates and estimates of disease expectancy were determined for a 'broad' diagnostic group of schizophrenic illness and for CATEGO S+ cases. While the former showed significant differences among the centres, the differences in the rates for S+ cases were non-significant or marginal. The results provide strong support for the notion that schizophrenic illnesses occur with comparable frequency in different populations and support earlier findings that the prognosis is better in less industrialized societies.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033291700011910

Early manifestations and first-contact incidence of schizophrenia in different cultures. A preliminary report on the initial evaluation phase of the WHO Collaborative Study on determinants of outcome of severe mental disorders.

A five-year follow-up of the patients initially included in the International Pilot Study of Schizophrenia was conducted in eight of the nine centres. Adequate information was obtained for 807 patients, representing 76% of the initial cohort. Clinical and social outcomes were significantly better for patients in Agra and Ibadan than for those in the centres in developed countries. In Cali, only social outcome was significantly better.

/pdf/the-international-pilot-study-of-schizophrenia-five-year-274fs3id53.pdf

The International Pilot Study of Schizophrenia: five-year follow-up findings.

This study reports on the findings from a WHO sponsored cross-national investigation of life events and schizophrenia. Data are presented from a series of 386 acutely ill schizophrenic patients selected from nine field research centers located in developing and developed countries (Aarhus, Denmark; Agra, India; Cali, Colombia; Chandigarh, India; Honolulu, USA; Ibadan, Nigeria; Nagasaki, Japan; Prague, Czechoslovakia; Rochester, USA). On a methodological level, the study demonstrates that life event methodologies originating in the developed countries can be adapted for international studies and may be used to collect reasonably reliable and comparable cross-cultural data on psychosocial factors affecting the course of schizophrenic disorders. Substantive findings replicate the results of prior studies which conclude that socioenvironmental stressors may precipitate schizophrenic attacks and such events tend to cluster in the two to three week period immediately preceding illness onset.

Stressful life events preceding the acute onset of schizophrenia: a cross-national study from the World Health Organization

We conducted a one-year follow-up of patients who had made a first contact with psychiatric services in Chandigarh, North India, and had been assigned a diagnosis of schizophrenia. The expressed emotion (EE) of the patients' relatives was assessed early on. We found the same associations between the individual components of EE and relapse of schizophrenia as in previous Anglo-American studies, but only the association between hostility and relapse was statistically significant. Applying the same criteria as in the Anglo-American studies for 'high EE', we found a significant relationship between high EE and relapse rates. We conclude that the significantly better outcome of Chandigarh first-contact patients compared with a London sample is largely due to the significantly lower proportion of high-EE relatives in the North Indian sample.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/D3332B183138980945A9C2A37B573F71/S0007125000216024a.pdf/div-class-title-expressed-emotion-and-schizophrenia-in-north-india-div.pdf

G. Ernberg

Papers

Schizophrenia: manifestations, incidence and course in different cultures. A World Health Organization ten-country study.

Early manifestations and first-contact incidence of schizophrenia in different cultures. A preliminary report on the initial evaluation phase of the WHO Collaborative Study on determinants of outcome of severe mental disorders.

The International Pilot Study of Schizophrenia: five-year follow-up findings.

Stressful life events preceding the acute onset of schizophrenia: a cross-national study from the World Health Organization

Expressed Emotion and Schizophrenia in North India: III. Influence of Relatives' Expressed Emotion on the Course of Schizophrenia in Chandigarh