The primary goal of the Life Histories and Health in Midlife Study was to conduct detailed analyses of the life histories and mental health statuses of a highly selected subsample of the Wisconsin Longitudinal Study (WLS), and subsequently link these data to new physical health data on general health, immune function, and neurophysiology. This study was conducted in 1997, under the leadership of Carol Ryff, Burton Singer, Richard Davidson, Daniel Muller, and colleagues.

A total of 354 individuals were invited to participate in the study; 202 completed the survey components (home interview and mail questionnaire). The mail questionnaire was sent to the respondent's home approximately 2 weeks prior to the interview and picked up by the interviewer. Among this group 122 completed at least one of the biological components of the study. Participation in three of the four clinical assessments required the respondent to spend the night at the General Clinical Research Center (GCRC) at the University of Wisconsin Hospital. During this visit, subjects provided blood and urine samples for analysis, received a complete, non-invasive physical examination, and participated in the laboratory study of emotions. For the immune assessment, the project nurse traveled to the respondent's home to administer the influenza vaccination and collect blood samples. Subjects could chose to participate in just the immune assessment (n=16), just the GCRC visit (n=21) or both (n=85).

There are 4 separate modules:

1. Interview Data: information about the respondent's spouse, work, siblings, children, religion, caregiving and receiving (202 cases).
   
   
2. Mail Questionnaire Data: information about relationships, attitudes and values, health, spirituality, and right/left handedness (202 cases).
   
   
3. Life Event Data: information about life events experienced across the respondents lifetime as reported in both the mail questionnaire and the home interview (202 cases).
   
   
4. Biological Data: information about physical characteristics as well as data from a complete physical, immune function assessment and a neurophysiology assessment (106 cases).