UCLA survey reveals extent of at-home COVID-19 testing, and attitudes toward vaccination and masks in California 

Data from the California Health Interview Survey finds one third of California adults will not get additional COVID-19 vaccine doses if recommended by health guidelines

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UCLA CHPR Communications Team

Although the Centers for Disease Control and Prevention has advised people to get fully vaccinated against COVID-19, findings from the 2023 California Health Interview Survey Preliminary COVID-19 Estimates Dashboard show that 32% of California adults said they would decline any additional COVID-19 doses.

The survey found that California adults who have not completed the primary vaccine series against COVID-19 did not do so for several reasons: 48% think a vaccine for COVID-19 is unnecessary, 45% worried about side effects, and 44% think the vaccine was developed too quickly. Additionally, 22% said they don’t know enough about the vaccine to make the decision to get it, and 20% don’t believe in vaccines in general. 

The dashboard, published today by the UCLA Center for Health Policy Research (CHPR), uses data collected from 5,088 California adults, children, and teenagers who completed the survey in March and April 2023. The findings include information about Californians’ experiences with personal and financial impacts of the pandemic, COVID-19 testing, access to masks, and experiences with long-lasting COVID-19 symptoms.

Among other findings, more than half (55%) of California adults have ever received a positive test for COVID-19, and among those who received a positive test, 47% received the result from a self-test kit only, 25% from a clinic, lab, or other testing site only, and 28% from both a testing site and a self-test kit. 

“Early on in the pandemic, COVID-19 testing was predominantly at testing sites, doctor’s offices, hospitals, and labs, which reported positive tests to local and statewide health departments. What this survey tells us is that nearly half of Californians received their positive result only from a self-test kit, which is not reported to health departments unless the individual reports it themselves. This may indicate COVID-19 positivity rates are higher than what has been reported,” said Todd Hughes, director of the California Health Interview Survey. “This research has been critical in helping us better understand how behaviors and perspectives have developed throughout the pandemic.”

Other highlights include:

Long COVID

  • 28% of California adults who tested positive for COVID-19 have experienced COVID-19 symptoms for two months or longer. 
  • Latinx adults were significantly more likely to experience COVID-19 symptoms for two months or longer (40%), compared to white adults (20%) and Asian adults (14%).
  • 41% of adults with the lowest incomes (0–99% of the federal poverty level) experienced COVID-19 symptoms for two months or longer compared to 23% of adults with the highest incomes (300% of the federal poverty level and above).

Access to highly protective masks

  • 1 in 3 — or 33% of — California adults said they do not have an N95, KN95, or KF94 mask.
  • Among California adults who did not have an N95, KN95, or KF94 mask, 16% said they would not wear a N95, KN95, or KF94 mask if public health recommended it as a COVID-19 protection.
  • 61% of California adults who do say they would not be able to get an N95, KN95, or KF94 mask said they are too expensive.
  • Nearly half — or 48% of — California adults with the lowest incomes (0–99% of the federal poverty level) said they did not have an N95, KN95, or KF94 mask, nearly double the 25% of adults with the highest incomes (300% of the federal poverty level and above) who did not have one.

Personal impacts of the pandemic

  • 1 in 9 — or 11% of — California adults said they have financial difficulties with paying their rent or mortgage.17% of Latinx adults experienced financial difficulties with paying their rent or mortgage, more than two times higher than 6% of white adults.
  • 22% of California adults who reported that they had not completed the primary COVID-19 vaccine series had financial difficulties with paying rent or mortgage compared to 10% who had completed the vaccine series.

COVID-19 vaccination status and testing

  • Among California adults who have completed the primary vaccine series for COVID-19, 22% have not received additional doses or boosters after the primary vaccine series for COVID-19.
  • 2 in 3 — or 66% of — California adults who lived in households with five or more people received a positive COVID-19 test, significantly higher than 37% of adults with one person in the household.

“The dashboard offers critical insights into attitudes surrounding COVID-19 in California,” said Ninez A. Ponce, PhD, MPP, director of the center and principal investigator of the California Health Interview Survey. “By collecting data on Californians’ views on vaccines, access to masks, long COVID symptoms, and other COVID experiences, this dashboard allows us to dig deeper into some of the ongoing patterns and inequities among Californians. It provides valuable insights to guide evidence-based policy decisions as we continue to recover from the COVID-19 pandemic.” 

Some of the dashboard findings are highlighted in an infographic.


About the UCLA Center for Health Policy Research
The UCLA Center for Health Policy Research (CHPR) is one of the nation’s leading health policy research centers and the premier source of health policy information for California. UCLA CHPR improves the public’s health through high quality, objective, and evidence-based research and data that informs effective policymaking. UCLA CHPR is the home of the California Health Interview Survey (CHIS) and is part of the UCLA Fielding School of Public Health​.