COVID-19 Follow-up Update #1

Purpose of the study

In light of the impact of the COVID-19 pandemic and the corresponding social restrictions to society, we followed up with a sample of our participants to see how they are impacted by the recent events. We would like to thank the WSTR twins for their participation and continued support of the WSTR.


The first wave of the follow-up survey was collected between April 20 2020 and May 3 2020 via an online platform. Individual response rate was 76.8% (3066 out of 3993), and pair-wise response rate (i.e., both twins completed survey) was 72.8% (760 out of 1044 pairs).

Changes in mental health

In both surveys, participants were asked to respond to a series of questions designed to assess depression, stress, and anxiety. There was no substantial difference in depression (Mbaseline = 1.02, Mfollowup = 0.98) between the two time points. Compared to baseline, participants showed slightly lower levels of stress (Mbaseline = 12.3, Mfollowup = 11.18) and anxiety (Mbaseline = 3.59, Mfollowup = 2.99) in the follow-up survey.

These preliminary results showed slight decrease in stress and anxiety in the month since our initial baseline survey. As social restriction measures are slowly easing in many countries, we will continue to track whether individuals’ levels of stress and anxiety change over time.