Table 3

Percentage of Ambulatory Primary and Preventive Care Visits Stratified by Insurance Group and ACA Period

Continuously Uninsureda (n = 28,834)Gained Medicaidb (n = 20,766)Gained Other Insurancec (n = 17,171)No Post-ACA Period Ambulatory Care Visitsd (n = 71,475)
Overall ambulatory care visit rates per patient per period
Pre-ACA period, rate4.644.575.472.18
Post-ACA period, rate4.006.297.59
Pre/post rate change−0.64Ref1.72e2.12e
Overall ambulatory care visits, No. (%)
Pre-ACA period
 0
 1-212,150 (42.1)9,579 (46.1)6,603 (38.5)54,450 (76.2)
 3-58,998 (31.2)6,123 (29.5)5,030 (29.3)12,462 (17.4)
 ≥67,686 (26.7)5,064 (24.4)5,538 (32.3)4,563 (6.4)
Post-ACA period
 0
 1-214,298 (49.6)7,009 (33.8)3,177 (18.5)
 3-58,195 (28.4)6,180 (29.8)5,475 (31.9)
 ≥66,341 (22.0)7,577 (36.5)8,519 (49.6)
Primary care visits, No. (%)
Pre-ACA period
 02,310 (8.0)901 (4.3)975 (5.7)12,631 (17.7)
 1-212,406 (43.0)9,681 (46.6)6,646 (38.7)45,693 (63.9)
 3-58,722 (30.2)6,153 (29.6)5,232 (30.5)10,144 (14.2)
 ≥65,396 (18.7)4,031 (19.4)4,318 (25.1)3,007 (4.2)
Post-ACA period
 02,595 (9.0)462 (2.2)364 (2.1)
 1-214,210 (49.3)7,297 (35.1)3,858 (22.5)
 3-57,758 (26.9)6,393 (30.8)5,989 (34.9)
 ≥64,271 (14.8)6,614 (31.9)6,960 (40.5)
Preventive care visits, No. (%)
Pre-ACA period
 024,228 (84.0)18,508 (89.1)14,696 (85.6)66,499 (93.0)
 1-24,590 (15.9)2,254 (10.9)2,465 (14.4)4,971 (7.0)
 3-516 (0.1)4 (0)10 (0.1)5 (0)
Post-ACA period
 024,839 (86.1)16,942 (81.6)12,883 (75.0)
 1-23,971 (13.8)3,792 (18.3)4,232 (24.6)
 3-524 (0.1)32 (0.2)56 (0.3)
  • ACA = Patient Protection and Affordable Care Act; Ref = reference group.

  • Notes: Pre-ACA = January 1, 2012 to December 31, 2013; Post-ACA = January 1, 2014 to December 31, 2015.

  • Visits refer to ambulatory care only.

  • Overall ambulatory care use includes all billable encounters. Primary care Current Procedural Terminology codes: 99201-99205, 99212-99215, 99241-99245, 99381-99387, 99391-99397. Preventive care Current Procedural Terminology codes: 99385-99387, 99395-99397.

  • Pairwise insurance-group differences between Continuously Uninsured vs Gained Medicaid, Continuously Uninsured vs Gained Other Insurance, and Continuously Uninsured vs No Post-ACA Period Ambulatory Care Visits were statistically significant for overall, primary care, and preventive care visits (P <.05).

  • a All preperiod visits were uninsured, and all postperiod visits were uninsured.

  • b All preperiod visits were uninsured, and all postperiod visits were covered by Medicaid with the following exception: to allow for time to enroll in Medicaid, the first visit post-ACA could be uninsured.

  • c All preperiod visits were uninsured, and during the post-ACA period, visits were covered by other insurance types or insurance patterns (churning).

  • d All preperiod visits were uninsured, and there were no visits during the post-ACA period.

  • e Statistically significant (P < .05) interaction terms between insurance groups by time period using a Poisson regression model.