Project on Human Development in Chicago Neighborhoods

The city of Chicago was selected as the research site for the PHDCN because of its extensive racial, ethnic, and social-class diversity. The project collapsed 847 census tracts in the city of Chicago into 343 neighborhood clusters (NCs) based upon seven groupings of racial/ethnic composition and three levels of socioeconomic status. The NCs were designed to be ecologically meaningful. They were composed of geographically contiguous census tracts, and geographic boundaries, and knowledge of Chicago's neighborhoods were considered in the definition of the NCs. Each NC was comprised of approximately 8,000 people.

Longitudinal Cohort Study

For the Longitudinal Cohort Study, a stratified probability sample of 80 neighborhoods was selected. The 80 NCs were sampled from the 21 strata (seven racial/ethnic groups by three socioeconomic levels) with the goal of representing the 21 cells as equally as possible to eliminate the confounding between racial/ethnic mix and socioeconomic status. Once the 80 NCs were chosen, then block groups were selected at random within each of the sample neighborhoods. A complete listing of dwelling units was collected for all sampled block groups. Pregnant women, children, and young adults in seven age cohorts (birth, 3, 6, 9, 12, 15, and 18 years) were identified through in-person screening of approximately 40,000 dwelling units within the 80 NCs. The screening response rate was 80 percent. Children within six months of the birthday that qualified them for the sample were selected for inclusion in the Longitudinal Cohort Study. A total of 8,347 participants were identified through the screening. Of the eligible study participants, 6,228 were interviewed in the Wave 1 data collection and 5,338 were interviewed in the Wave 2 data collection.

Data collection for Wave 2 began in 1997 and ended in 2000. It included a letter sent to study participants notifying them that they would be contacted to schedule an interview. This letter explained the study, reimbursements, and offered a monthly drawing prize of $1,000 for those participants who kept their first scheduled appointment. A toll free number was also included in the letter, so participants could call and schedule their own interviews or ask questions.

For all cohorts except 0 and 18, primary caregivers as well as the child were interviewed. The primary caregiver was the person found to spend the most time taking care of the child. Separate research assistants administered the primary caregiver interviews and the child interviews. The primary method of data collection was face-to-face interviewing, although participants who refused to complete the personal interview were administered a phone interview. An abbreviated telephone interview was conducted for the primary caregivers in Cohorts 0-15 and Cohort 18 study participants in Wave 2 who lived outside the nine-county metropolitan area to which research assistants were able to travel for interviews. A total of 221 telephone interviews were conducted during Wave 2, representing 3.55 percent of the sample.

Proxy interviews were conducted with study participants who were emancipated minors (under 18 but married or living independently). The study participants answered questions from the primary caregiver's interview on the primary caregiver's behalf. In Wave 2, four primary caregivers and two study participants were interviewed in jail. Study participants in foster care could not be interviewed. The Department of Children and Family Services did not allow interviews of the foster parent or the child. Permission was granted for a brief period in Wave 1, therefore there are some children in the sample who could not be followed up in Waves 2 and 3. Some children were not in foster care in Wave 1 but were placed in foster care by Wave 2 or 3. They were also not followed up. Lastly, some participants were interviewed in Wave 3 but not in Wave 2, as they were in foster care during Wave 2.

Some participants in Wave 1 spoke a language other than English, Spanish, or Polish. In Wave 2, an abbreviated version of the primary caregiver's protocol was administered, and the research assistant arranged for someone in the household to translate on the spot. In Wave 2, the complete protocol was translated into Spanish, and a subset of the primary caregiver's interview was translated into Polish.

Depending on the age and wave of data collection, participants were paid between $5 and $20 per interview. Other incentives, such as free passes to museums, the aquarium, and monthly drawing prizes were also included.

Interview protocols included a wide range of questions. For example, some questions assessed impulse control and sensation-seeking traits, cognitive and language development, leisure activities, delinquency and substance abuse, friends' activities, and self-perception, attitudes, and values. Caregivers were also interviewed about family structure, parent characteristics, parent-child relationships, parent discipline styles, family mental health, and family history of criminal behavior and drug use.

Family Suicide Interview

The Family Suicide Interview was administered to subjects' caregivers for Cohorts 0 to 15. The instrument was adapted from a section of the Major Depression Disorder module of the Diagnostic Interview Schedule for Children (DISC 4) and obtained information regarding any members of the subject's family who had committed suicide.