Hello Miriam,
You may explore the following variables in the main Study -file w_indresp
| variable |
label |
| w_istrtdathh |
Individual interview start time (hours) |
| w_istrtdatmm |
Individual interview start time (minutes) |
| w_istrtdatss |
Individual interview start time (seconds) |
| w_istrtdaty |
Interview start date (year) |
| w_istrtdatm |
Interview start date (month) |
| w_istrtdatd |
Interview start date (day) |
| w_ienddathh |
Time at end of individual interview (hours) |
| w_ienddatmm |
Time at end of individual interview (minutes) |
| w_ienddatss |
Time at end of individual interview (seconds) |
| w_ienddaty |
Date at end of individual interview (year) |
| w_ienddatm |
Date at end of individual interview (month) |
| w_ienddatd |
Date at end of individual interview (day) |
| w_intdatd_dv |
Interview date: Day, derived |
| w_intdatm_dv |
Interview date: Month, derived |
| w_intdaty_dv |
Interview date: Year, derived |
The following in the COVID-19 Survey – file cw_indresp_w
| variable |
label |
| cw_surveystart |
Date and time survey interview started |
| cw_surveyend |
Date and time survey interview ended |
| cw_ff_intd |
Date of the last monthly interview the respondent completed- day |
| cw_ff_intm |
Date of the last monthly interview the respondent completed- month |
| cw_ff_inty |
Date of the last monthly interview the respondent completed- year |
The variables cw_surveystart and cw_surveyend are not available in the April wave (ca_indresp_w) but you may use variables cw_ff_intd, cw_ff_intm and cw_ff_inty on the May wave to impute the dates to the April wave.
You may also explore the Calendar Year Dataset, 2020 if you want to join Covid-19 Survey to Main Study. The Calendar Year 2021 dataset is still in process, therefore you'll need to combine waves 11, 12, and 13 as they collectively provide information for the year 2021 to merge 2021 Covid-19 Survey waves. For further information on the Calendar year dataset, please refer to User Guide - Calendar Year Dataset 2020 at https://www.understandingsociety.ac.uk/sites/default/files/downloads/documentation/user-guides/calendar_year_dataset_2020_user_guide.pdf
I hope this information is helpful.
Best wishes,
Roberto Cavazos
Understanding Society User Support Team
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