Background/objectives: The coronavirus disease 2019 (COVID-19) pandemic has taken a disproportionate toll on long-term care facility residents and staff. Our objective was to review the empirical evidence on facility characteristics associated with COVID-19 cases and deaths.

Design: Systematic review.

Setting: Long-term care facilities (nursing homes and assisted living communities).

Participants: Thirty-six empirical studies of factors associated with COVID-19 cases and deaths in long-term care facilities published between January 1, 2020 and June 15, 2021.

Measurements: Outcomes included the probability of at least one case or death (or other defined threshold); numbers of cases and deaths, measured variably.

Results: Larger, more rigorous studies were fairly consistent in their assessment of risk factors for COVID-19 outcomes in long-term care facilities. Larger bed size and location in an area with high COVID-19 prevalence were the strongest and most consistent predictors of facilities having more COVID-19 cases and deaths. Outcomes varied by facility racial composition, differences that were partially explained by facility size and community COVID-19 prevalence. More staff members were associated with a higher probability of any outbreak; however, in facilities with known cases, higher staffing was associated with fewer deaths. Other characteristics, such as Nursing Home Compare 5-star ratings, ownership, and prior infection control citations, did not have consistent associations with COVID-19 outcomes.

Conclusion: Given the importance of community COVID-19 prevalence and facility size, studies that failed to control for these factors were likely confounded. Better control of community COVID-19 spread would have been critical for mitigating much of the morbidity and mortality long-term care residents and staff experienced during the pandemic. Traditional quality measures such as Nursing Home Compare 5-Star ratings and past deficiencies were not consistent indicators of pandemic preparedness, likely because COVID-19 presented a novel problem requiring extensive adaptation by both long-term care providers and policymakers.