Table 2.
Difference-in-differences in number of new treatments (DMFTnew) and surfaces (DMFSnew) after Philadelphia beverage tax implementation
| Pre-tax Mean (SD)a | Post-tax Mean (SD)a | ||||
|---|---|---|---|---|---|
| Outcome | Philadelphia | Control | Philadelphia | Control | Difference-in-differences (95% CI)b |
| Older children/adults | |||||
| DMFTnew | |||||
| Panel | 0.51 (1.15) | 0.49 (1.14) | 0.28 (0.79) | 0.31 (0.93) | −0.02 (−0.08, 0.03) |
| Cross-section | 0.62 (1.40) | 0.64 (1.48) | 0.46 (1.20) | 0.55 (1.45) | −0.05 (−0.11, 0.01) |
| Cross-section, ever-Medicaid | 0.87 (1.86) | 0.77 (1.71) | 0.65 (1.48) | 0.72 (1.76) | −0.18 (−0.34, −0.03) |
| Cross-section, never-Medicaid | 0.56 (1.26) | 0.62 (1.43) | 0.40 (1.08) | 0.49 (1.33) | −0.02 (−0.08, 0.03) |
| DMFSnew | |||||
| Panel | 1.35 (3.46) | 1.35 (3.29) | 0.91 (2.72) | 1.03 (3.44) | −0.06 (−0.29, 0.17) |
| Cross-section | 1.76 (4.66) | 1.91 (5.16) | 1.38 (4.13) | 1.73 (5.26) | −0.11 (−0.37, 0.14) |
| Cross-section, ever-Medicaid | 2.69 (6.86) | 2.46 (6.30) | 2.02 (5.34) | 2.36 (6.91) | −0.64 (−1.27, −0.01) |
| Cross-section, never-Medicaid | 1.54 (3.93) | 1.79 (4.90) | 1.16 (3.60) | 1.53 (4.66) | 0.00 (−0.23, 0.22) |
| Younger children | |||||
| DMFTnew | |||||
| Panel | 0.49 (1.39) | 0.52 (1.56) | 0.32 (0.94) | 0.31 (0.93) | 0.07 (−0.08, 0.23) |
| Cross-section | 0.56 (1.53) | 0.76 (1.99) | 0.41 (1.20) | 0.77 (2.21) | −0.16 (−0.33, 0.02) |
| Cross-section, ever-Medicaid | 0.66 (1.64) | 0.89 (2.15) | 0.49 (1.29) | 0.94 (2.45) | −0.22 (−0.46, 0.01) |
| Cross-section, never-Medicaid | 0.42 (1.36) | 0.63 (1.82) | 0.27 (1.01) | 0.49 (1.62) | 0.04 (−0.15, 0.22) |
| DMFSnew | |||||
| Panel | 1.48 (5.08) | 1.63 (6.02) | 0.99 (3.44) | 0.94 (3.45) | 0.43 (−0.22, 1.09) |
| Cross-section | 1.66 (5.69) | 2.57 (7.91) | 1.31 (4.55) | 2.91 (9.43) | −0.70 (−1.49, 0.09) |
| Cross-section, ever-Medicaid | 1.96 (5.99) | 3.04 (8.56) | 1.56 (4.92) | 3.66 (10.65) | −1.03 (−2.05, −0.01) |
| Cross-section, never-Medicaid | 1.23 (5.25) | 2.10 (7.16) | 0.88 (3.85) | 1.68 (6.52) | 0.30 (−0.59, 1.18) |
Note: Boldface indicates statistical significance (p<0.05).
a
Weighted by inverse probability of treatment weights.
b
Difference-in-differences models were fit with generalized estimating equations weighted by inverse probability of treatment weights with variables for group (Philadelphia=1, control=0), period (pre-tax=0, post-tax=1), and a group
*
period interaction, which estimated the difference-in-differences.