. Author manuscript; available in PMC: 2023 Sep 11.

Published in final edited form as: Pediatrics. 2020 Dec;146(6):e20200213. doi: 10.1542/peds.2020-0213

TABLE 3.

Comparison of Participating and Control Practice Mean Asthma-Related ED Visit Rates From Baseline and Postcollaborative Years (Main Difference-in-Differences Analysis)

Main Analysis	Asthma-Related ED Visits per 100 Child-Years	P	95% Confidence Interval
Main Analysis	Asthma-Related ED Visits per 100 Child-Years	P	Lower	Upper
Control 2014	16.97	—	11.99	21.95
Participating 2014	15.29	—	11.62	18.96
Control 2017	18.80	—	12.89	24.71
Participating 2017	9.50	—	7.07	11.93
Difference in differences	−7.62	.002	−13.45	−1.78

Marginal rates are adjusted for patient (age, sex, and insurance) and practice (specialty, organizational structure, size, geographic region, and FQHC or RHC) characteristics and, also, for patients clustering within practices; SEs are estimated by using the δ method; Coefficients for relative rates are in Supplemental Table 6. —, not applicable.