Method

Estimated policy effect on absolute health inequality^{a}(reduced rate difference in % points, [95% CI])

Estimated policy effect on relative health inequality^{b} (reduced rate ratio, in %, [95% CI])


1. Regression adjustment

1.97 [1.19, 2.76]

12.20 [4.49, 19.90]

2. Matching

1.89 [1.77, 2.02]

11.60 [8.99, 14.20]

3. Differenceindifferences

1.85 [0.88, 2.82]

11.33 [1.37, 21.29]

4. Fixed effects

1.82 [1.28, 2.36]

12.26 [5.45, 19.08]

5. Instrumental variable

2.02 [1.34, 2.69]

12.62 [6.07, 19.17]

6. Regression discontinuity

not comparable

not comparable

7. Interrupted timeseries

1.85 [1.45, 2.26]

11.53 [6.05, 17.00]

Real policy effect

1.86

11.25

Simple beforeandafter comparison

0.86

−22.03


^{a}We calculated the prevalence of people having poor health in each educational group following the real policy implementation and the predicted prevalence if leaving out the term for the policy effect (when there was no policy). The reported numbers represent the absolute reduction of the rate difference that can be attributed to the policy

^{b}The reported numbers represent the relative reduction of the rate ratio (RR) calculated as follows: (RR_{without policy} – RR_{with policy})/(RR_{without policy} ‐ 1) * 100