Impact of the COVID-19 Pandemic on Health Care Utilization in the Vaccine Safety Datalink: Retrospective Cohort Study

Lei Qian   ¹ , PhD ;   Lina S Sy   ¹ , MPH ;   Vennis Hong   ¹ , MPH ;   Sungching C Glenn   ¹ , MS ;   Denison S Ryan   ¹ , MPH ;   Jennifer C Nelson   ² , PhD ;   Simon J Hambidge   ³ , MD, PhD ;   Bradley Crane   ⁴ , MS ;   Ousseny Zerbo   ⁵ , PhD ;   Malini B DeSilva   ⁶ , MD, MPH ;   Jason M Glanz   ⁷ , PhD ;   James G Donahue   ⁸ , DVM, PhD ;   Elizabeth Liles   ⁴ , MD, MCR ;   Jonathan Duffy   ⁹ , MD, MPH ;   Stanley Xu   ^{1, 10} , PhD

¹ Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA, United States

² Kaiser Permanente Washington Health Research Institute, Seattle, WA, United States

³ Denver Health Ambulatory Care Services, Denver, CO, United States

⁴ Center for Health Research, Kaiser Permanente Northwest, Portland, OR, United States

⁵ Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, CA, United States

⁶ HealthPartners Institute, Bloomington, MN, United States

⁷ Institute for Health Research, Kaiser Permanente Colorado, Aurora, CO, United States

⁸ Marshfield Clinic Research Institute, Marshfield, WI, United States

⁹ Centers for Disease Control and Prevention, Atlanta, GA, United States

¹⁰ Department of Health Systems Science, Kaiser Permanente Bernard J. Tyson School of Medicine, Pasadena, CA, United States