Appendix Table 1.

The Multivariate Analysis of Factors Affecting Hospitalization Among Veterans at VHA Primary Care Clinics Across the United States and in King County, WA in 2015

VariablesOdds Ratio; P-Value (95% CI)
United StatesKing County, WA
Model 1Model 2Model 3Model 4Model 1Model 2Model 3Model 4
Age, Years1.003; <.001 (1.003 to 1.0031)1.003; <.001 (1.002 to 1.0034)1.003; <.001 (1.003 to 1.0034)1.003; <.001 (1.003 to 1.0034)1.02; <.001 (1.01 to 1.028)1.02; <.001 (1.01 to 1.026)1.02; <.001 (1.01 to 1.029)1.05; <.001 (1.01 to 1.02)
Sex, female as reference1.17; <.001 (1.15 to 1.18)1.16; <.001 (1.14 to 1.18)1.16; <.001 (1.15 to 1.18)1.17; <.001 (1.15 to 1.18)1.18;.13 (0.95 to 1.47)1.18; .13 (0.95 to 1.47)1.17; .14 (0.95 to 1.46)1.18; .13 (0.95 to 1.46)
Reported race, non-white as reference0.85; <.001 (0.84 to 0.853)0.85; <.001 (0.84 to 0.86)0.85; <.001 (0.84 to 0.854)0.84; <.001 (0.83 to 0.85)0.91; .13 (0.81 to 1.03)0.91; .13 (0.81 to 1.03)0.91; .12 (0.81 to 1.03)0.92; .18 (0.82 to 1.04)
Gagne Comorbidity Score*, 0/ below 0 as Reference3.33; <.001 (3.30 to 3.35)3.33; <.001 (3.30 to 3.35)3.33; <.001 (3.30 to 3.35)3.33; <.001 (3.30 to 3.35)3.71; <.001 (3.33 to 4.14)3.72; <.001 (3.33 to 4.15)3.71; <.001 (3.20 to 4.14)3.69; <.001 (3.30 to 4.12)
NSES Index
    1st quartile as reference
    2nd Quartile0.82; <.001 (0.81 to 0.83)0.81; <.001 (0.80 to 0.82)0.80; <.001 (0.79 to 0.81)0.80; <.001 (0.79 to 0.81)0.99; .95 (0.84 to 1.18)0.96; .67 (0.81 to 1.14)1.005; .94 (0.85 to 1.20)1.04; .64 (0.87 to 1.24)
    3rd Quartile0.74; <.001 (0.73 to 0.75)0.73; <.001 (0.72 to 0.735)0.71; <.001 (0.70 to 0.72)0.71; <.001 (0.70 to 0.72)0.89; .29 (0.74 to 1.06)0.84; <.05 (0.71 to 1.10)0.85; .84 (0.72 to 1.02)0.89; .21 (0.75 to 1.07)
    4th Quartile0.67; <.001 (0.66 to 0.68)0.66; <.001 (0.65 to 0.664)0.63; <.001 (0.631 to 0.64)0.63; <.001 (0.629 to 0.64)0.71; <.001 (0.59 to 0.85)0.65; <.001 (0.55 to 0.77)0.68; <.001 (0.58 to 0.81)0.70; <.001 (0.59 to 0.82)
Housing issues
    Housing instability1.01; <.001 (1.00 to 1.012)1.01; <.001 (1.00 to 1.03)
    Home vacancy rate§1.07; <.001 (1.01 to 1.017)0.99; .73 (0.97 to 1.02)
    Characteristics of the house
    Percentage of houses with no plumbing1.00; <.01 (1.001 to 1.008)1.07; <.05 (1.02 to 1.11)
    Percentage of houses with no heating0.99; <.001 (0.98 to 0.992)1.10; <.05 (1.05 to 1.15)
QIC24642332464261246453324639869956.7179960.1489951.1539943.414
  • * Gagne comorbidity score was presented as a binary variable (above 0 vs. 0 and below 0) in the GEE model.

  • The NSES index was a summary measure of six geographic-level census-based variables linked to the census tract of a participant's residence. The higher values corresponded to higher socioeconomic status.

  • Percentage of households that moved across census tracts in the past year and had an income below 100% poverty line.

  • § Percentage of vacant houses in each census tract.

  • The QIC (Quasi likelihood under the Independence model Criterion) statistic is analogous to the AIC (Akaike's Information Criterion) statistic used for comparing models fit with likelihood-based methods. Since the GEE method is not a likelihood-based method, the AIC statistic is not available. Smaller QIC value presents a better model.

  • Model 1. GEE Model—Patient-level characteristics, NSES index, housing instability.

  • Model 2. GEE Model—Patient-level characteristics, NSES index, home vacancy rate.

  • Model 3. GEE Model—Patient-level characteristics, NSES index, percentage of of houses with no plumbing.

  • Model 3. GEE Model—Patient-level characteristics, NSES index, percentage of of houses with no heating.

  • GEE, Generalized Estimating Equation; NSES, neighborhood socioeconomic status; VHA, Veterans Health Administration.