Characteristics of States, CHCs, and Encounter Rates Before and After Medicaid Expansion
| Expansion States8 | Nonexpansion States8 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Characteristic | CA | MN | OH | OR | WA | Total | AK | IN | MT | NC | Total |
| State-level factors | |||||||||||
| Adult Medicaid eligibility,a pre-22/post-8 expansion period, % of FPL | 106/138 | 215/205 | 96/138 | 39/138 | 71/138 | – | 78/128 | 24/24 | 54/54 | 47/45 | – |
| Minimum wage, 2014,19 $/hr | 8.00 | 7.25 | 7.95 | 9.10 | 9.32 | – | 7.50 | 7.25 | 7.90 | 7.25 | – |
| Unemployment rate, 2014,20 % | 7.6 | 4.6 | 5.5 | 6.9 | 6.1 | – | 6.4 | 5.7 | 4.6 | 6.4 | – |
| Adult uninsured rate, 2013,21 % | 21.6 | 9.5 | 13.9 | 19.4 | 16.8 | – | 18.9 | 15.3 | 20.7 | 20.4 | – |
| Insurance marketplace23 | State | State | Federal | Stateb | State | – | Federal | Federal | Federal | Federal | – |
| OCHIN CHC characteristics | |||||||||||
| Primary care CHCs, No. | 29 | 4 | 14 | 85 | 5 | 137 | 1 | 9 | 5 | 4 | 19 |
| Total patients, 2013–June 2014, No. | 91,282 | 7,912 | 30,422 | 156,440 | 14,571 | 300,356c | 2,198 | 10,244 | 9,014 | 11,861 | 33,315c |
| Female sex, No. (%) | 54,890(60.1) | 4,477 (56.6) | 18,045 (59.3) | 93,620 (59.8) | 8,819 (60.5) | 179,675 (59.8)d | 1,221 (55.6) | 6,700 (65.4) | 5,265 (58.4) | 7,004 (59.1) | 20,188 (60.6) |
| Age-group, as of last visit, No. (%) | |||||||||||
| 19 to 25 y | 12,356 (13.5) | 1,318 (16.7) | 5,466 (18.0) | 23,078 (14.8) | 2,202 (15.1) | 44,386 (14.8)d | 347 (15.8) | 1,469 (14.3) | 1,876 (20.8) | 1,269 (10.7) | 4,961 (14.9) |
| 26 to 39 y | 29,037 (31.8) | 2,920 (36.9) | 10,052 (33.0) | 52,389 (33.5) | 4,696 (32.2) | 99,000 (33.0) | 760 (34.6) | 3,091 (30.2) | 2,569 (28.5) | 2,683 (22.6) | 9,102 (27.3) |
| 40 to 64 y | 49,889 (54.7) | 3,674 (46.4) | 14,904 (49.0) | 80,973 (51.8) | 7,673 (52.7) | 156,970 (52.3) | 1,091 (49.6) | 5,684 (55.5) | 4,569 (50.7) | 7,909 (66.7) | 19,252 (57.8) |
| Household income, No. (%) | |||||||||||
| ≤138 % of FPL | 60,107 (65.8) | 5,415 (68.4) | 24,214 (79.6) | 114,117 (72.9) | 11,338 (77.8) | 214,958 (71.6)d | 718 (32.7) | 7,507 (73.3) | 5,431 (60.3) | 5,410 (45.6) | 19,066 (57.2) |
| >138 % of FPL | 11,416 (12.5) | 523 (6.6) | 2,962 (9.7) | 24,645 (15.8) | 3,118 (21.4) | 42,628 (14.2) | 1,016 (46.2) | 1,038 (10.1) | 2,181 (24.2) | 2,822 (23.8) | 7,055 (21.2) |
| Missing/unknown | 19,759 (21.6) | 1,974 (24.9) | 3,246 (10.7) | 17,678 (11.3) | 115 (0.8) | 42,770 (14.2) | 464 (21.1) | 1,699 (16.6) | 1,402 (15.6) | 3,629 (30.6) | 7,194 (21.6) |
| Nonwhite race, No. (%) | 7,914 (8.7) | 6,191 (78.2) | 15,365 (50.5) | 14,709 (9.4) | 1,033 (7.1) | 45,192 (15.0)d | 647 (29.4) | 5,704 (55.7) | 332 (3.7) | 6,783 (57.2) | 13,466 (40.4) |
| Hispanic ethnicity, No. (%) | 41,999 (46.0) | 125 (1.6) | 4,331 (14.2) | 38,243 (24.4) | 1,472 (10.1) | 86,145 (28.7)d | 227 (10.3) | 1,041 (10.2) | 336 (3.7) | 491 (4.1) | 2,095 (6.3) |
| Urban residence, No. (%) | 88,368 (96.8) | 7,841 (99.1) | 30,410(100.0) | 147,320(94.2) | 13,518 (92.8) | 287,204 (95.6)d | 2,172 (98.8) | 10,195 (99.5) | 8,083 (89.7) | 8,886 (74.9) | 29,335 (88.1) |
| Adjustede visit RRs, postexpansion period vs preexpansion periodf | |||||||||||
| Total visits, RR (95% CI) | 0.99 (0.93–1.05) | 1.05 (1.03–1.08)g | 1.02 (0.94–1.10) | 1.07 (1.03–1.11)g | 1.34 (1.00–1.79) | 1.05 (1.01–1.08)g | 0.94h | 0.99 (0.76–1.28) | 0.94 (0.85–1.05) | 0.93 (0.80–1.08) | 0.95 (0.87–1.04) |
| Uninsured visits, RR (95% CI) | 0.92 (0.78–1.09) | 0.75 (0.65–0.87)g | 0.82 (0.71–0.94)g | 0.51 (0.45–0.59)g | 0.64 (0.54–0.75)g | 0.60 (0.54–0.67)g | 0.84h | 0.88 (0.68–1.14) | 0.83 (0.78–0.88)g | 0.78 (0.57–1.07) | 0.84 (0.74–0.95)g |
| Medicaid visits, RR (95% CI) | 1.03 (0.94–1.12) | 1.11 (1.03–1.19)g | 1.17 (1.07–1.29)g | 1.78 (1.60–1.98)g | 2.04 (1.39–2.99)g | 1.36 (1.24–1.49)g | 1.07h | 1.18 (0.86–1.62) | 1.03 (1.00–1.07) | 0.96 (0.81–1.12) | 1.05 (0.94–1.18) |
| Commercially insured visits, RR (95% CI) | 1.08 (0.92–1.27) | 0.99 (0.90–1.09) | 1.22 (1.09–1.37)g | 0.96 (0.89–1.05) | 1.03 (0.84–1.27) | 1.02 (0.94–1.09) | 0.96h | 1.20 (0.89–1.61) | 1.01 (0.82–1.24) | 1.03 (0.99–1.06) | 1.03 (0.96–1.11) |
AK= Alaska; CA = California; CHC = community health center; FPL = federal poverty level; GEE = generalized estimating equation; IN = Indiana; MN = Minnesota; MT= Montana; NC = North Carolina; OCHIN = formerly the Oregon Community Health Information Network; OH = Ohio; OR= Oregon; RR = rate ratio; WA = Washington.
↵a Eligibility FPL levels may differ between adults with children and without, or those who are working and those who are jobless. The number reported indicates the highest FPL limit for open full Medicaid coverage in a given state among these categories.
↵b Because of problems with its state exchange rollout, Oregon opted to switch to the federal exchange in mid-2014.
↵c Expansion group numbers may not sum because an individual patient can have visits in more than 1 state.
↵d Overall percentage differs significantly between expansion states and nonexpansion states by χ2 test (P < .001).
↵e Rates by state: Poisson GEE model adjusted for CHC-level factors (percent female, percent younger than age 40 years, percent nonwhite, percent Hispanic, percent ≤138% FPL, percent with unknown FPL, percent urban). Rates by expansion status: Poisson GEE model adjusted for all CHC-level factors plus state-level factors (2014 minimum wage, 2014 unemployment rate, 2013 adult uninsurance rate). All GEE models accounted for temporal correlation over time within CHCs.
↵f Preexpansion period: January 1, 2013, to December 31, 2013; postexpansion period: January 1, 2014, to June 30, 2014.
↵g RR is significantly different from 1.0.
↵h CI cannot be computed because Alaska had only 1 CHC in the sample.