Methods

This section of the Web site contains information to help secondary analysts understand the methods used to gather and analyze this complex data collection.

ICPSR staff will continue to add content to this section, as it becomes available. We currently provide information on the following topics:

• Site Selection
  Rationale for selecting the city of Chicago

• Sampling
  Sampling strategies for all components of the PHDCN data collection

• Response Rates
  Response rates for the Longitudinal Cohort Study

• Units of Analysis
  Explanation of units of analysis for all data components

• Instruments and Measures
  Detailed information about the numerous instruments and measures used in all components of the PHDCN data collection

• Scales
  Information about scales created by PHDCN's Scientific Directors

• Imputations
  Information about imputations for Primary Caregiver variables in the Longitudinal Cohort Study

• Statistical Modeling
  "The Role of Statistical Modeling in the Project"
  Winter 1998 PHDCN Newsletter article by Stephen Raudenbush

• Spanish and Polish Translation of Instruments
  "The Translation Process: Expanding the Utility and Validity of the Project Protocol"
  Spring 1996 PHDCN newsletter article by Lorrie Stone and Chris Payne

• PHDCN Glossary
  Definitions of terms as used in the PHDCN data collection