TABLE 5.

Unadjusted trends and regression‐adjusted changes in the percent of patients outpatient visits, quality measures, and health care utilization events, for Primary Care Provider (PCP) switchers vs. stayers (among all plan switchers) before and after January 2015, 2014—2016 (N = 7339)

Outcomes	Percent of patients per quarter, before Jan. 2015	Percent of patients per quarter, after Jan. 2015	Adjusted percentage‐point difference‐in‐difference	95% CI
Outpatient visits
PCP stayer	74	68
PCP Switcher	70	64	0.58	−0.8, 2
Asthma outpatient visits
PCP stayer	12	8.6
PCP switcher	9.7	8.3	1.6***	0.72, 2.5
Rx adherence
PCP stayer	28	23
PCP switcher	26	21	0.57	−1.5, 2.6
Asthma Med ratio
PCP stayer	61	47
PCP switcher	57	44	0.78	1.7, 3.2
ED visits
PCP stayer	14	14
PCP switcher	16	16	0.84	−0.26, 1.9
Asthma ED visits
PCP stayer	2	1.5
PCP switcher	2.5	2.1	0.09	−0.33, 0.51
Hospitalization rate
PCP stayer	<1%	<1%
PCP switcher	<1%	<1%	0.11	−0.14, 0.37
IP asthma
PCP stayer	<1%	<1%
PCP switcher	<1%	<1%	0.07	−0.08, 0.21

The second and third columns represent the unadjusted percent of patients who ever have an outpatient visit, hospitalization, or ED visit in a given quarter, and the percent of patients who were adherent to asthma medication in a given year. The fourth column shows the adjusted difference‐in‐difference in outcomes, which is given as the percentage‐point change in the percent of patients with an outcome from the preswitch period to the postswitch period. The 95% confidence interval is the range of likely values associated with the treatment effect. Primary care provider is abbreviated as PCP. Asthma medication adherence is abbreviated as Rx adherence. The asthma medication ratio is abbreviated as Asthma Med Ratio. Hospitalizations for asthma are abbreviated as IP Asthma. Emergency department is abbreviated as ED.

^* P < .05; **P < .01; ***P < .001.