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. 2020 Feb 10;20:100. doi: 10.1186/s12913-020-4896-1

Table 3.

Negative binomial regression model: Association between length of stay, insurance type, and other factorsa

Safety-net hospitalsb Non-safety-net hospitalsb
Coefficient Std. Error p-value 95% CI % change Coefficient Std. Error p-value 95% CI % change
Demographics
 Age (Referent: Age 70 years and over)
  0–17 − 0.59 0.15 0.000 [− 0.89, − 0.29] −44.8 −0.48 0.13 0.000 [−0.73, − 0.23] − 38.3
  18–29 − 0.13 0.08 0.121 [− 0.29, 0.03] − 12.2 0.00 0.12 0.972 [− 0.24, 0.23] − 0.4
  30–49 − 0.04 0.04 0.298 [−0.12, 0.04] −4.1 − 0.09 0.06 0.130 [−0.21, 0.03] −8.6
  50–69 0.05 0.02 0.029 [0.01, 0.1] 5.2 0.03 0.02 0.110 [−0.01, 0.06] 2.7
 Gender (Referent: Male)
  Female −0.06 0.01 0.000 [−0.08, − 0.04] −5.7 −0.06 0.01 0.000 [−0.08, − 0.04] −5.7
 Race (Referent: White)
  Black/African American 0.20 0.07 0.003 [0.07, 0.33] 22.4 0.16 0.04 0.000 [0.09, 0.23] 17.3
  Other 0.08 0.04 0.043 [0, 0.16] 8.4 0.00 0.03 0.942 [−0.05, 0.05] −0.2
 Ethnicity (Referent: Non-Spanish/Hispanic)
  Spanish/Hispanic 0.06 0.04 0.121 [−0.02, 0.13] 6.1 −0.01 0.05 0.762 [−0.11, 0.08] −1.5
  Multiple ethnicities −0.02 0.13 0.867 [−0.28, 0.24] −2.2 0.05 0.11 0.661 [−0.17, 0.27] 5.0
  Unknown −0.03 0.06 0.664 [−0.15, 0.1] −2.7 0.06 0.05 0.230 [−0.04, 0.16] 6.3
Clinical Indicators
 Type of admission (Referent: Otherc)
  Emergency, Trauma, Urgent −0.54 0.11 0.000 [−0.75, − 0.33] −41.7 −0.44 0.10 0.000 [−0.62, − 0.25] −35.3
 APR-DRG severity of Illness (Referent: Minor)
  Moderate 0.12 0.02 0.000 [0.09, 0.15] 12.4 0.09 0.01 0.000 [0.07, 0.11] 9.5
  Major 0.26 0.02 0.000 [0.22, 0.31] 30.1 0.25 0.01 0.000 [0.22, 0.28] 28.0
  Extreme 0.79 0.04 0.000 [0.71, 0.87] 120.3 0.71 0.04 0.000 [0.64, 0.78] 103.6
 APR-DRG risk of mortality (Referent: Minor)
  Moderate 0.11 0.02 0.000 [0.08, 0.14] 11.4 0.13 0.01 0.000 [0.11, 0.16] 14.2
  Major 0.28 0.02 0.000 [0.24, 0.31] 31.8 0.33 0.02 0.000 [0.29, 0.36] 38.4
  Extreme 0.46 0.04 0.000 [0.38, 0.54] 58.3 0.50 0.03 0.000 [0.44, 0.57] 65.6
Hospital Indicators
 Health insurance type (Referent: Commericald)
  Medicaid 0.24 0.04 0.000 [0.16, 0.33] 27.3 0.20 0.03 0.000 [0.14, 0.27] 22.3
  Medicare 0.04 0.03 0.136 [−0.01, 0.1] 4.4 0.00 0.02 0.952 [−0.04, 0.04] −0.1
  Dual Eligible (Medicaid/Medicare) 0.06 0.05 0.228 [−0.04, 0.15] 6.0 0.01 0.02 0.687 [−0.04, 0.06] 1.0
  Self-pay −0.04 0.06 0.543 [−0.15, 0.08] −3.5 −0.02 0.05 0.733 [−0.11, 0.08] −1.6
  Other/unknowne 0.19 0.04 0.000 [0.1, 0.28] 21.0 0.12 0.05 0.024 [0.02, 0.22] 12.3
 Disposition (Referent: Homef)
  Expired −0.29 0.06 0.000 [−0.42, − 0.17] −25.3 −0.35 0.04 0.000 [−0.43, − 0.26] −29.2
  Inpatient rehabilitation facility −0.03 0.07 0.653 [−0.17, 0.1] −3.0 −0.05 0.03 0.150 [−0.11, 0.02] −4.6
  Nursing home/long term careg 0.19 0.10 0.059 [−0.01, 0.39] 21.1 −0.03 0.05 0.499 [−0.13, 0.06] −3.3
  Skilled nursing facility −0.03 0.05 0.469 [−0.12, 0.06] −3.3 0.01 0.02 0.720 [−0.04, 0.05] 0.8
  Otherh −0.22 0.08 0.004 [−0.36, − 0.07] −19.4 −0.28 0.04 0.000 [−0.36, − 0.2] −24.6
N 16,310 32,638

Note. a. hospital type includes safety-net hospitals and non-safety-net hospitals where safety-net hospitals were defined as hospitals with a payer mix consisting of at least 30% of Medicaid and uninsured payers. b. illustrated statistics are coefficients and percent change amounts calculated through negative binomial regression models; the sample consisted of hip fracture patients from the SPARCS database with full covariate information; standard errors and 95% confidence intervals for the coefficients are also reported. c. other types of admission include: elective, newborn, and not available. d. commercial insurance includes: Blue Cross/Blue Shield; managed care, unspecific; and private health insurance. e. other insurance represents: Department of Corrections; federal/state/local/VA; other/miscellaneous; and unknown. f. patient discharged to: home or self-care; home with home health service; hospice (home); or left against medical advice. g. Medicaid Certified Nursing Home; Medicare Certified Long Term Care facility. h. patient discharged to: another facility not listed; cancer center or children’s hospital; court/law enforcement; critical access hospital; facility with custodial/supportive care; federal health care facility; hospital-based Medicare approved swing bed; hospice-medical facility; psychiatric hospital; short-term hospital