Purpose: To assess the difference in crude rates and age-adjusted rates in COVID-19 cases.
Methods: COVID-19 cases in Virginia were obtained from the publicly available dataset as of June 21, 2020. Crude rates of COVID -19 cases were calculated and estimates for the total population of Virginia were age-adjusted to the U.S. Census 2000 population using the direct method.
Results: There was a wide difference between the crude rate and the age-adjusted rate in the different age-groups. The crude rate was highest for the over 80 age group, 1063.93 per 100,000 population. However, the age-adjusted rate was highest in the 40-49 years age group, 147.72 per 100,000 followed by the 30-39 group and 20-29 group.
Conclusion: Comparing the crude rates and age-adjusted rates of COVID-19 cases takes into account the confounding effect of age due to differences in the distribution of a population. Given the risk and higher COVID-19 cases among certain age-groups, knowing the crude rates and the age-adjusted rates may help in population-based prevention and interventions and can be used for planning capabilities and targeted measures.
Pattah, Priyadarshini PhD, MPH and Anson-Dwamena, Rexford MPH
"Using Age-Adjusted and Crude Rates for Assessing COVID-19 Cases,"
Virginia Journal of Public Health: Vol. 4:
3, Article 8.
Available at: https://commons.lib.jmu.edu/vjph/vol4/iss3/8