KFF COVID-19 Vaccine Monitor: In Their Own Words, Six Months Later

This KFF COVID-19 Vaccine Monitor: In Their Own Words, Six Months Later was designed and analyzed by public opinion researchers at the Kaiser Family Foundation (KFF). The survey was conducted June 15-23, 2021 using the SSRS Opinion Panel, a nationally representative panel of U.S. adults age 18 or older recruited using probability-based sampling techniques. For the Kaiser Family Foundation, SSRS re-invited adult panelists in the U.S. who previously participated in a survey in January 14-18, 2021. The original sampling targeted panel respondents by gender, age, race, education, and region. SSRS regularly monitored data collection to check for demographic composition of the sample and data quality. Cases determined to be poor-quality, as defined by surveys with a length of interview of less than 33% of the mean length of interview and with invalid text responses were removed from the final data. In total, 1,009 panelists were invited to participate in this follow-up survey and 878 respondents completed the full questionnaire online on June 15-23, 2021 with additional follow-ups conducted on July 2,2021. 859 surveys were completed in English and 19 surveys were completed in Spanish. Panelists were compensated for their participation, with incentives distributed by the SSRS Opinion Panel through their standard procedures.

The margin of sampling error including the design effect for the full sample is plus or minus 4 percentage points. Numbers of respondents and margins of sampling error for key subgroups are shown in the table below. For results based on other subgroups, the margin of sampling error may be higher. Sample sizes and margins of sampling error for other subgroups are available by request. Note that sampling error is only one of many potential sources of error in this or any other public opinion poll. Kaiser Family Foundation public opinion and survey research is a charter member of the Transparency Initiative of the American Association for Public Opinion Research.