Table 2

Segmented regression analysis of primary and secondary outcomes

Level before implementationMonthly slope before implementation*Level change after implementationChange in slope after implementation†
Estimate95% CIP valueEstimate95% CIP valueEstimate95% CIP valueEstimate95% CIP value
Inappropriate omissions
Medical18.0812.31 to 23.85<0.001−0.07−0.69 to 0.560.83−13.38−17.73 to −9.02<0.0010.37−0.35 to 1.080.30
Surgical11.924.47 to 19.360.003−0.24−1.18 to 0.690.60−5.50−13.89 to 2.890.190.72−0.48 to 1.930.23
Surgical non-linear‡−8.28−15.73 to −0.830.031
Total omissions
Medical28.0021.42 to 34.60<0.0010.11−0.62 to 0.840.77−11.07−19.56 to −2.570.0130.05−0.88 to 0.980.91
Surgical24.8317.58 to 32.07<0.001−0.60−1.49 to 0.280.17−2.71−9.76 to 4.340.431.280.12 to 2.450.03
Surgical non-linear‡−5.54−12.77 to 1.690.13
  • *The monthly slope before implementation determines the baseline trend.

  • †The change in slope after implementation compares the difference between the pre-implementation and post-implementation slopes.

  • ‡The level change after implementation after accounting for the non-linear shape of the pre-implementation period.