DOI: 10.3886/icpsr02760
title: Midlife in the United States (MIDUS 1), 1995-1996
title: Archival Version

description: The Midlife in the United States (MIDUS) is a collaborative, interdisciplinary investigation of patterns, predictors, and consequences of midlife development in the areas of physical health, psychological well-being, and social responsibility. A description of the study and findings from it are available at http://www.midus.wisc.edu. 
The first wave of the MIDUS study (MIDUS 1 or M1) collected survey data from a total of 7,108 participants. The baseline sample was comprised of individuals from four subsamples: (1) a national RDD (random digit dialing) sample (n=3,487); (2) oversamples from five metropolitan areas in the U.S. (n=757); (3) siblings of individuals from the RDD sample (n=950); and (4) a national RDD sample of twin pairs (n=1,914). All eligible participants were non-institutionalized, English-speaking adults in the coterminous United States, aged 25 to 74.
Data from the samples were collected primarily in 1995/96. The survey (Project 1) dataset contains responses from a 30-minute Phone interview and two 50-page Self-Administered Questionnaire (SAQ) instruments. Of the 7,108 respondents who completed the Phone interview, 6,325 also completed the SAQ. 
This updated version of the study is comprised of three primary datasets:
Dataset 1, Main, Siblings, and Twin Data, contains responses from the main survey of 7,108 respondents. Respondents were asked to provide extensive information on their physical and mental health throughout their adult lives, and to assess the ways in which their lifestyles, including relationships and work-related demands, contributed to the conditions experienced. Those queried were asked to describe their histories of physical ailments, including heart-related conditions and cancer, as well as the treatment and/or lifestyle changes they went through as a result. A series of questions addressed alcohol, tobacco, and illegal drug use, and focused on history of use, regularity of use, attempts to quit, and how the use of those substances affected respondents' physical and mental well-being. Additional questions addressed respondents' sense of control over their health, their awareness of changes in their medical conditions, commitment to regular exercise and a healthy diet, experience with menopause, the decision-making process used to deal with health concerns, experiences with nontraditional remedies or therapies, and history of attending support groups. Respondents were asked to compare their overall well-being with that of their peers and to describe social, physical, and emotional characteristics typical of adults in their 20's, 40's, and 60's. Information on the work histories of respondents and their significant others was also elicited, with items covering the nature of their occupations, work-related physical and emotional demands, and how their personal health had correlated to their jobs. An additional series of questions focusing on childhood queried respondents regarding the presence/absence of their parents, religion, rules/punishments, love/affection, physical/verbal abuse, and the quality of their relationships with their parents and siblings. Respondents were also asked to consider their personal feelings of accomplishment, desire to learn, sense of control over their lives, interests, and hopes for the future.
<strong>The Datasets previously numbered 2 and 3 have been removed to avoid redundancies, and all datasets have been renumbered.</strong> Please refer to the readme file.
Dataset 2, Twin Screener Data, provides the first national sample of twin pairs ascertained randomly via the telephone.
Dataset 3, Coded Text Responses, describes how open-ended textual responses in the MIDUS 1 Computer-Assisted Telephone Interview (CATI) and Self-Administered Questionnaire (SAQ) were transformed into categorical numeric codes. These codes are included in a stand-alone dataset containing only those cases (N=3,950) that contained text data in their responses.
Online Analysis Only: Datasets 1, 2, and 3 were merged together by the SU_ID variable to form "Merged Data with Weights (Online Analysis Only)" (Dataset 4) for online analysis capabilities.
 MIDUS also maintains a
Colectica portal, which allows users to interact with variables across waves and create customized subsets. Registration is required.
description: A series of sampling and post-stratification weights were created for the national Random-Digit Dialing (RDD) sample. For additional information, please refer to the weighting documentation provided for the data collection.
description: Response Rates: The response rate for the national Random-Digit Dialing (RDD) sample was 70 percent. The Self-Administered Questionnaire (SAQ) follow-up response rate was 89 percent.
description: Presence of Common Scales: 
Generalized Anxiety Disorder (GAD) Scale
Somatic Amplification Scale
The Alcohol Screening Test
The Conflict Tactics (CT) Scales
The Revised Conflict Tactics Scales (CTS2)
Loyola Generativity Scale (LGS)

Many scales were constructed for use in the Midlife in the United States (MIDUS 1), 1995-1996 Study. For additional information on scale construction and sources, please refer to the scale documentation included with the data collection.
description: Respondents were drawn from a nationally representative random-digit-dial sample of non-institutionalized, English-speaking adults, aged 25-74, selected from working telephone banks in the coterminous United States. Those queried participated in an initial telephone interview and responded to a mail questionnaire. Please see the Descriptions of Midlife in the United Sates (MIDUS) Samples documentation provided by ICPSR for more detailed information.
description: Datasets: 
DS0: Study-Level Files
DS1: Main, Siblings and Twin Data
DS2: Twin Screener Data
DS3: Coded Text Data
DS4: Merged Data with Weights (Online Analysis Only)
description: Respondents were drawn from a nationally representative random-digit-dial sample of non-institutionalized, English-speaking adults, aged 25-74, selected from working telephone banks in the coterminous United States. Those queried participated in an initial telephone interview and responded to a mail questionnaire. Smallest Geographic Unit: None
description: computer-assisted telephone interview (CATI); mail questionnaire; self-enumerated questionnaireAdditional information about the Midlife Development in the United States study can be found at the MIDUS Web site.All data files in the MIDUS study (both longitudinal and cross-sectional) can be linked using a key variable called <strong>M2ID</strong>.The DDI codebook (PDF file) and the XML file (contained in a .zip package) released by ICPSR were provided by MIDUS and were not changed in any way by ICPSR. These original files do not reflect any of the processing done by ICPSR.The title of this study was changed from National Survey of Midlife Development in the United States (MIDUS), 1995-1996, to Midlife in the United States (MIDUS 1), 1995-1996, on May 9, 2017.Removed: Dataset 2, Main Sample: Weights for Respondents Completing Both the Telephone Survey and Mail Questionnaire, and Dataset 3, Main Sample: Weights for Respondents Completing at least the Telephone Survey, contained weighting information and variables that are now incorporated in Dataset 1, Main, Siblings, and Twin Data. All datasets have been renumbered consecutively.