TABLE 4

Hospital-Based Usage by Study Group and Study Period: Difference-of-Differences Analysis

OutcomeMonthControlInterventionDifference in Change From Baseline
Baseline150181
12150176
18a149176
Estimated Usage, Mean (95% CI)Pq valueb
ED visits per child-yearcBaseline0.28 (0.20–0.40)0.32 (0.24–0.43)
120.20 (0.14–0.29)0.29 (0.21–0.40).33.17
180.19 (0.13–0.27)0.25 (0.18–0.34).51.23
Inpatient admissions per child-yearcBaseline0.57 (0.43–0.74)0.70 (0.56–0.88)
120.38 (0.28–0.51)0.51 (0.40–0.65).67.27
180.28 (0.21–0.39)0.31 (0.23–0.41).53.23
Hospital d per child-yearcBaseline1.21 (0.86–1.71)1.34 (0.98–1.81)
120.49 (0.34–0.70)0.84 (0.61–1.14)<.0001.003
180.33 (0.23–0.47)0.50 (0.37–0.69).0006.009
LOS, d per child-yeard Baseline1.93 (1.74–2.14)1.98 (1.80–2.18)
121.67 (1.50–1.86)1.90 (1.72–2.09).25.17
181.45 (1.30–1.61)1.50 (1.36–1.65).89.33
LOS > 7 d per child-yeard Baseline0.14 (0.09–0.22)0.11 (0.07–0.17)
120.02 (0.01–0.05)0.07 (0.04–0.11).008.06
180.02 (0.01–0.05)0.04 (0.02–0.08).11.15
ICU visits per child-yearc Baseline0.08 (0.05–0.14)0.11 (0.07–0.17)
120.04 (0.02–0.09)0.07 (0.04–0.12).70.28
180.04 (0.02–0.08)0.04 (0.02–0.08).79.31
Death over the study, n (%)1 (0.7%)3 (1.7%).63.26
  • a At 12 mo, the intervention group lost 5 children (2 moves and 3 deaths); at 18 mo, the control group lost 1 child (because of death).

  • b Adjusted for multiple comparisons by using the false discovery rate, significant when ≤0.10.

  • c Winsorized at the 99th percentile and analyzed by using Poisson regression.

  • d Winsorized at the 99th percentile and log-transformed before analysis. The marginal mean estimates and CIs were back-transformed by using the Duan smearing factor and are presented in the original units (d per admission).