Table 3.

Most important model features associated with postacute sequelae of COVID-19 ranked by absolute Shapley value. Model created using electronic health record data from a sample of patients included in the National COVID Cohort Collaborative during the COVID-19 pandemic. For additional information regarding covariates, see Multimedia Appendix 2.

Feature	Absolute Shapley value, mean
Observation period length	0.075
Number of health care interactions during the acute COVID-19 period	0.045
Viral lower respiratory infection during the acute COVID-19 period	0.040
Age (years)	0.038
Ethnicity unknown	0.037
Total number of health care interactions associated with a diagnosis during the post–COVID-19 period	0.035
Systemic corticosteroid use before acute COVID-19	0.025
Index acute COVID-19 date	0.024
State missing	0.019
State Utah	0.016
State Ohio	0.016
Acute respiratory disease during the acute COVID-19 period	0.013
Creatinine concentration in blood	0.012
Never smoker	0.011
Total health care interactions associated with a diagnosis during the baseline period	0.011
Cough during the acute COVID-19 period	0.011
Cough during the post–COVID-19 period	0.011
State Colorado	0.010
Creatinine volume	0.010
SARS-CoV-2 RNA presence	0.010