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Table 6 Interrupted time series (ITS) segmented regression analysis: difference-in-difference (DID) estimates, comparing treatment (dual-eligibles enrolled in D-SNP) vs. comparator (individuals 60–64 enrolled in Medicaid Managed Care) on changes in monthly utilization time trends associated with DSNP Regulations, Across Racial/ethnic Group

From: The impact of Dual Eligible Special Need Plan regulations on healthcare utilization

 

Post Period (vs. Pre Period)

Sample

Outcome

DID LevelA

P-Value

DID SlopeB

P-Value

Non-Hispanic White1

Any Hospitalization

−0.45%

0.28

−0.04%

0.22

Any ED Visit

−0.21%

0.69

−0.01%

0.89

Non-Hispanic Black22

Any Hospitalization

−0.70%

0.37

0.01%

0.87

Any ED Visit

−1.53%

0.10

−0.00%

0.99

Hispanic3

Any Hospitalization

−1.10%

0.14

−0.01%

0.84

Any ED Visit

−0.96%

0.33

0.02%

0.73

  1. Notes: Linear regression used for utilization outcomes. Sample is person-months from 2010 to 2015. Regression covariates include Group (treatment vs. comparator); a linear monthly time trend, indicators and splines for the post period (2012–2015); and the interactions between these variables. Other covariates included sex, age, indicator for SSI status, 18 comorbidity indicators, and state fixed effects. Repeated measures adjusted for using Huber-White robust standard errors, clustering at the person level. 1. N = 205,371 2. N = 90,506 3. N = 64,528
  2. A. Difference between treatment vs. comparator in the discontinuity (change in level) for the post period, measured using the interaction between Group & an indicator variable for the post period
  3. B. Difference between treatment vs. comparator in the change in slope for the post period, measured using the interaction between Group & a spline variable for the post period