Authors describe the methodologic approach to rapidly launching a population-based surveillance study in spring 2020 to examine the lasting physical, mental, and economic effect of COVID-19 among adults in Michigan. Authors randomly selected adults with polymerase chain reaction–confirmed SARS-CoV-2 infection in the Michigan Disease Surveillance System. From 2020 through 2022, respondents completed detailed surveys on the lasting effect of their COVID-19 illness online in English or by telephone in English, Spanish, or Arabic, reflecting the diverse population in Michigan.  

Findings: Of all sampled people (n = 17 584), 5521 completed our baseline survey a median of 4.5 months after their COVID-19 onset, for a response rate of 32.1%. Most respondents completed the survey online in every region except Detroit, where 67.1% completed the survey by telephone, highlighting the importance of multimode surveys to increase accessibility and generalizability. Our findings suggest minimal nonresponse bias in the weighted baseline sample.