The results of the first statewide random sample study in the United States to measure the spread of COVID-19 indicated a general population prevalence of about 2.8 percent in Indiana. The results of ...

Survey researchers increasingly recognize that a single survey of the general public can rarely represent the views of small groups of Americans. Such surveys frequently have too few interviews with ...

Pew Research Center designed this study to assess the current state of online survey sampling methods – both probability-based and opt-in – and determine their accuracy on general population estimates ...

The study is based on a random sample that included people with asymptomatic infections. Vaccines protect well against severe disease.