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The Consolidated Human Activity Database — Master Version (CHAD-Master) Technical Memorandum

This short technical memo describes the contents of the CHAD-Master database. The database consists of two files, a Questionnaire file that contains demographic and daily variables for each diary-day in CHAD. The corresponding Events file contains the minute-by-minute human activity record (activities and locations) for each diary day. The two files are both indexed by a unique CHADID for each diary-day.

This memo includes a number of tables describing the studies currently included in CHAD-Master, descriptions of all available CHAD-Master variables, an inventory of questionnaire and events variables by study, and definitions for all codes associated with these variables.

  • The Consolidated Activity Database -- Master Version (CHAD-Master) Technical Memorandum, Sept. 2014 (pdf) (590.18 KB, Sept. 2014)

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Last updated on February 21, 2025
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