Survey Solutions Survey
Solutions Documentation and knowledge base

Date and Time formats

June 27, 2018

This document uses the following notation to describe the date and time formats:

  • Y - year
  • M - month
  • D - day
  • h - hour
  • m - minute
  • s - second
  • T - exactly letter T
  • {AM|PM} - one of the two time specifications AM or PM.
  • Mon - month abbreviated to 3 letters
  • Month - full month name.
  • DOW - day of week (such as Monday, Tuesday, etc).
  • TZ - timezone

Exported data

Survey Solutions writes date and time as strings in exported data files. Here is how:

In the main data file:

  • Date questions: YYYY-MM-DD
  • Timestamp (date question with the current time option): YYYY-MM-DDThh:mm:ss in the device timezone.
  • Timestamp in GPS location question: YYYY-MM-DDThh:mm:ss in UTC timezone.
  • Calculated variable of type DateTime: YYYY-MM-DDThh:mm:ss without timezone adjustment.

In the interview_actions file:

  • Date: YYYY-MM-DD
  • Time: hh:mm:ss in UTC time zone

In the interview_comments file:

  • Date: MM/DD/YYYY
  • Time: hh:mm:ss in UTC time zone

In the survey paradata file:

  • Event timestamp: YYYY-MM-DDThh:mm:ss based on the server or tablet clock (as applicable*), adjusted for UTC time zone
  • Answer to the date question: YYYY-MM-DD
  • Answer to the date question with the current time option: YYYY-MM-DD hh:mm:ss based on the server or tablet clock (as applicable*) no adjustment for time zone.
  • Variable of DateTime type recalculated: M/D/YYYY h:m:s{AM|PM}, no adjustment for time zone.

In export__readme.txt file

  • DOW, Month DD, YYYY

In interviews.tab file (web links for assignments):

  • Date questions: YYYY-MM-DDT00:00:00
  • Timestamp (date question with the current time option): YYYY-MM-DDThh:mm:ss

Tablet clock is used for events registered on the tablet, such as answering an interviewer’s question in CAPI mode interviews. Server clock is used for events registered on the server, such as rejection of interview by a supervisor.

Interface

Survey Solutions displays date and time information in various places in the interface. Here is how:

  • In the Questionnaires list (imported on, modified on, and created on fields) and Assignments list (updated on and created on fields): Mon DD, YYYY hh:mm in the current user timezone.
  • In the Interview status history dialog accessed from interview details: Mon DD, YYYY hh:mm in the UTC timezone.
  • In the Interview status history dialog accessed from interview context menu: Mon DD, YYYY hh:mm in the current user timezone.
  • Timestamp in identifying questions: YYYY-MM-DD hh:mm:ss recorded in the current user timezone; displayed without further timezone adjustment for users in other timezones.
  • Timestamp in interviewer’s questions: YYYY-MM-DD hh:mm:ss recorded and displayed in the current user’s timezone. Other users will see it adjusted for their timezones.
  • On completion of web interviews: M/D/YYYY h:m:s{AM|PM}
  • In audit log: YYYY-MM-DD hh:mm:ss -TZ timestamp of the server event using server clock in server time zone with explicit specification of time difference vs UTC time.