In order to expand the data collected by the survey, and to collect data on life events closer to the time at which they occur, Understanding Society is testing methods to collect data on a more continual basis rather than just annually. The first round of ‘Event Triggered Data Collection’ was implemented in the IP from February 2020 until January 2021. At the beginning of each month, sample members were sent an invitation by email and/or SMS, inviting them to a web survey containing a single question about whether they had experienced any of a list of life events in the previous calendar month. If yes, they were asked a series of follow-up questions about each event reported. The data collected in these monthly surveys are deposited separately with the UK Data Service (SN: 8990, 10.5255/UKDA-SN-8990-1) and can be linked with the data from the annual IP interviews using the individual identifier “pidp”.
ff_eventeligw12 “Eligible for event trigged data collection experiment”
1 Eligible
2 Not eligible
Not all eligible sample members were invited to the Event Triggered Data Collection: individuals in a random 70% of households were invited, individuals in the remaining 30% of households were not invited and serve as the control group. This experiment is controlled by the variable ff_eventtrigw12 on record m_indsamp_ip:
ff_eventtrigw12 “Allocation to event-triggered data collection”
1 Allocated to event triggered data collection
2 Not allocated to event triggered data collection
The variable ff_eventissuw12 on record m_indsamp_ip identifies sample members who were issued to ETDC experiment. That is, they were eligible (ff_eventeligw12=1) and in the randomised treatment group invited to event-triggered data collection (ff_eventtrigw12=1):
ff_eventissuw12 “Issued to event-triggered data collection”
1 Issued
2 Not issued
The variables ff_eventeligw12, ff_eventtrigw12 and ff_eventissuw12 are set to Inapplicable (-8) for sample members who were not eligible for the annual interviews, for example because they were younger than 16, adamant refusers, or their address was unknown. In addition, there are 333 individuals who were to be issued to ETDC, but were returned from the wave 12 fieldwork as adamant refusals and were therefore dropped from the ETDC sample file.
The event triggered data collection included two experiments. The allocation variables for these are included in the sample file deposited with the event triggered data. The first is an incentive experiment (controlled by variable ff_eventincetw13): half of sample members were offered £1 for completing the monthly survey, half were offered £1 for completing the event question plus £2 if they reported any events. The second experiment concerned the timing of the two reminders that were sent after the initial invitation to the survey (controlled by variable ff_eventremindersw13): half of sample members were sent reminders daily, the other half were sent reminders every two days.
To acknowledge the event triggered data collection, the IP13 interview included some additional wording in the first question of the Annual Events History module (“calintro”) and a debrief question about the event triggered data collection (“eventdebrief”). These were routed on the variable ff_eventtrig_w12. However an error in the sample file for IP13 meant that this variable was set to missing for all sample members. Therefore this additional wording and the debrief question were erroneously not shown to any sample members.
