Association Between Sampling Method and Covid-19 Test Positivity Among Undergraduate Students: Testing Friendship Paradox in Covid-19 Network of Transmission

Kianersi, Sina; Ahn, Yong-Yeol; Rosenberg, Molly

In November 2020, we conducted a cross sectional study to implement and test the method of acquaintance sampling (randomly sampling friends of randomly sampled individuals) in detecting students with higher probability of COVID-19 positivity. Overall, 879 students were randomly sampled and participated in this study. In an online survey, the randomly sampled participants nominated a friend, and reported their own and their nominated friends COVID-19 status. Nominated friends were about 1.64 (95% CI: 1.33, 2.00) times more likely to have ever been infected with COVID-19, compared to randomly sampled students. Our study corroborates the effectiveness of acquaintance sampling for identifying members of networks with higher COVID-19 risk. These findings could be useful for university policy makers when developing mitigation testing programs and intervention strategies against COVID-19 spread.