The research used both single and multipollutant models and controlled for spatial trends and a comprehensive set of potential confounders, including state-level test positive rate, county-level healthcare capacity, phase-of-epidemic, population mobility, population density, sociodemographics, socioeconomic status, race and ethnicity, behavioral risk factors, and meteorology. County-level average NO2 concentrations were positively associated with both COVID-19 case-fatality rate and mortality rate in single-, bi-, and tri-pollutant models.
Hi Song, this is very interesting. Thanks for sharing! I’m curious about co-morbidities of COVID-19 deaths in the sample, and how that is reflected in the observed fatality rate of 3.8. I think picking that as a correlate makes a lot of sense - as opposed to positive cases - but my understanding is that ‘cause of death’ methodologies can be different from county to county. As such, if that’s true, I wonder to what extent that could be controlled for as a confounder. Would love to hear your thoughts.
@todd_hendricks Thanks! This is a very good point! The co-morbidities of COVID-19 deaths required the details from each county even each hospital but there is no such data available. In addition, since our model is a mix-effect model, the county-specific fixed effects should have been controlled in the longitudinal analysis. In other words, day-by-day variation of such effects within a county is small.
Thanks, Song. Well done. As an aside, this article clarifies where I was a little off base on standardization and co-morbidity. COVID-19 Deaths Are Mostly Caused By Coronavirus | by Gideon M-K; Health Nerd | Medium