The Collaborative Psychiatric Epidemiology Surveys (CPES), with support from the National Institute of Mental Health (NIMH), were initiated in recognition of the need for contemporary, comprehensive epidemiological data regarding the distributions, correlates, and risk factors of mental disorders among the general population with special emphasis on minority groups. The primary objective of the CPES was to collect data about the prevalence of mental disorders, impairments associated with these disorders, and their treatment patterns from representative samples of majority and minority adult populations in the United States. Secondary goals were to obtain information about language use and ethnic disparities, support systems, discrimination, and assimilation, in order to examine whether and how closely various mental health disorders are linked to social and cultural issues. To this end, CPES joins together three nationally representative surveys: the National Comorbidity Survey Replication (NCS-R), the National Survey of American Life (NSAL), and the National Latino and Asian American Study (NLAAS). These studies collectively provide the first national data with sufficient power to investigate cultural and ethnic influences on mental disorders. In this manner, CPES permits analysts to approach analysis of the combined dataset as though it were a single, nationally representative study. Each of the CPES studies has been documented in a comprehensive and flexible manner that promotes cross-survey linking of key data and scientific constructs. Each study represents an important exploration of the mental health status of specific populations. The following provides a brief description of each of the studies.
National Comorbidity Survey Replication (NCS-R)
The National Comorbidity Survey Replication (NCS-R) is a probability sample of the United States carried out a decade after the original 1992 NCS (NCS-1) was conducted. The NCS-R repeats many of the questions from the NCS-1 and also expands the questioning to include assessments based on the diagnostic criteria of the American Psychiatric Association as reported in the Diagnostic and Statistical Manual - IV (DSM-IV), 1994. The two major aims of the NCS-R were first, to investigate time trends and their correlates over the decade of the 1990s, and second, to expand the assessment in the baseline NCS-1 in order to address a number of important substantive and methodological issues that were raised by the NCS-1.
National Survey of American Life (NSAL)
The National Survey of American Life (NSAL) is a study designed to explore racial and ethnic differences in mental disorders, psychological distress, and informal and formal service use from within the context of a variety of presumed risk and protective factors in the African American and Afro-Caribbean populations of the United States as compared with white respondents living in the same communities.
National Latino and Asian American Study (NLAAS)
The National Latino and Asian American Study (NLAAS) is a nationally representative community household survey that estimates the prevalence of mental disorders and rates of mental health service utilization by Latinos and Asian Americans in the United States. The central aims of the NLAAS were three-fold. First, to describe the lifetime and 12-month prevalence of psychiatric disorders and the rates of mental health services use for Latino and Asian American populations using nationwide representative samples of these groups; second, to assess the associations among social position, environmental context, and psychosocial factors with the prevalence of psychiatric disorders and utilization rates of mental health services; and third, to compare the lifetime and 12-month prevalence of psychiatric disorders, and utilization of mental health services of Latinos and Asian Americans with national representative samples of non-Latino whites (drawn from the National Comorbidity Study-Replication (NCS-R) and African Americans (drawn from the National Survey of American Life (NSAL).
Although each of the three studies was managed by a separate staff, the data collection model was the same. Project managers and support staff were located at the Survey Research Center (SRC), part of the Institute for Social Research at the University of Michigan in Ann Arbor, Michigan. Teams of interviewers were located throughout the United States, supervised by team leaders and regional field managers. The staff of the three projects worked closely together and whenever possible used similar procedures and materials.
The core CPES questionnaire was based largely on the World Health Organization's (WHO) expanded version of the Composite International Diagnostic Interview (CIDI) developed for the World Mental Health (WMH) Survey initiative, the WMH-CIDI. All three projects used a modified version of the WMH-CIDI, which had been developed over the course of more than a year by an international group of collaborators. The design of the WMH-CIDI involved modifications and additions to the existing WHO-CIDI. The CIDI was an expansion of the Diagnostic Interview Schedule (DIS), the first standardized psychiatric diagnostic interview developed for administration by lay interviewers. The CIDI was designed to produce diagnoses based on WHO International Classification of Disease (ICD) criteria, while diagnoses from the DIS could only be made based on American Psychiatric Association (APA) Diagnostic and Statistical Manual (DSM) of Mental Disorders criteria.
The CPES facilitates accurate comparative work among the three studies, moving beyond the typical components of documentation (for example, static questionnaires and codebooks with frequencies, and descriptions of datasets), to dynamic and cross-linked Interactive Codebook using Web-based displays. The cross-linking features are designed to facilitate meaningful comparisons of mental health diagnoses, raw variable results, and questionnaire text. Researchers visiting the CPES website are able to search for items or variables related to a particular concept of condition (e.g., "depression"); review and compare variables discovered by the search, as well as linked related information (for example universe or imputation code) and related variables, and select variables for online analysis. For more information on CPES design and implementation, please consult the Web site User's Guide, Data Processing note and other supplementary documentations in the Using CPES.
Two issues of the International Journal of Methods in Psychiatric Research were devoted to the CPES project. You can read the articles in those issues:
For more in-depth information on the three studies that are part of the CPES, see also Publications for additional information. CPES investigators regularly hold instructional classes to expand use of these data. These training programs educate researchers about the background and goals of the three studies comprising CPES, the complexities of the instrumentation and datasets, the diagnostic algorithms and other constructed variables, the sample design and weights, appropriate techniques for the analysis of complex sample survey data, and concrete examples of analytic strategies. See Training Resources for further reference.
In addition, to see more specific information about CPES, the following sections provide detailed description about CPES design: