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There are seven instruments that collect physical activity data by self reports.

ACT24

The ACT24 is a web-based data collection instrument that allows participants to self-report their activity in the past 24 hours. Participants completed the ACT24 six times during the study with two months between tasks (administrations). At each assigned interval, the study center contacted participants and asked them to complete the ACT24 within 24 hours. Participants received email and telephone reminders from the study center to complete the ACT24. If the participant did not complete the ACT24 in the specified timeframe, it was reassigned three to five days after the missed completion date. An ACT24 administration was reassigned up to two times within the month before it was considered incomplete. In summary: each participant was allowed three attempts, assigned on different days, to complete the assigned ACT24 task for each interval. A few participants provided more than one complete ACT24 within a specified timeframe.

ACT24 data are provided in multiple files and formats:

  • 5-minute epoch files (contain multiple activities occurring within a 5 minute block and related MET information)
    • First complete ACT24 within scheduled timeframe (act24_5min.sas7bdat)
    • Additional complete ACT24s within scheduled timeframe (act24_5min_secondary_complete.sas7bdat)
    • Incomplete ACT24s (act24_5min_not_complete.sas7bdat)
  • Per Activity files (contain additional detailed information about each activity)
    • First complete ACT24 within scheduled timeframe (act24_activity.sas7bdat)
    • Additional complete ACT24s within scheduled timeframe (act24_activity_secondary_complete.sas7bdat)
    • Incomplete ACT24s (act24_activity_not_complete.sas7bdat)
  • Respondent files (contain information about participant interface with web-based system)

All free-text responses provided by participants have been removed from these data files. Activities with free-text responses were reviewed and either placed into existing activities defined by the ACT24, or in newly created activity levels if no appropriate predefined activity existed.

The ACT24 web tool provides MET levels according to the 2000 Compendium of Physical Activities. An up-converted set of MET levels using the 2011 Compendium of Physical Activities is also provided in these datasets.

Click here for data dictionaries and formats for the ACT24 files. Datasets can be obtained by submitting a request.

Summary
  • Self-reported activity data
  • 6 24-hour recalls approximately 2 months apart
  • ~935 participants with 1st completed recalls
Available Data
  • 5-Minute Files
    • Primary activity
    • Additional activities
    • MET Level, posture, intensity
    • Time/sequence
  • Activity Files
    • MET Level, posture, intensity
    • Time/sequence
    • Additional non-MET-related activity details (with whom, for what purpose, other specifics)
  • ACT24 Respondent: Person
    • Number of tasks attempted, total number of attempts, and total number of sessions
    • Time spent and number of sessions for each task and overall, for each of three measures:
      • The first complete attempt, if any, for each task
      • All attempts at each task until a complete attempt, or until the last attempt if none were complete
      • Total time spent for each task, including incomplete, first complete, and additional complete attempts
    • Arrays of tasks, summarizing data from the ACT 24 Respondent Task file
  • ACT24 Respondent: Task
    • Number of attempts
    • Time spent, number of sessions, and completion status for each attempt
    • Summary of time spent and number of sessions for the task, for each of three measures:
      • The first complete attempt, if any, for the task
      • All attempts at the task until a complete attempt, or until the last attempt if none were complete
      • All attempts for the task, including incomplete, first complete, and additional complete attempts
    • Link to the 5 Minute file for the related activity data
  • ACT24 Accounting
    • One record per person in the study
    • ACT24 compliance and timing