Impact of COVID-19 on Primary Care Practice Sites and Their Vulnerable Patients.

While COVID-19 has upended lives, it has also catalyzed innovation with potential to advance health delivery. Yet, we know little about how the delivery system, and primary care in particular, has responded and how this has impacted vulnerable patients. We aimed to understand the impact of COVID-19 on primary care practice sites and their vulnerable patients and to identify explanations for variation.