Table 5 Factors associated with the proportion of significant effect sizes
Model 1 | Model 2 | Model 3 | ||||
|---|---|---|---|---|---|---|
Average Marginal Effect (AME) | Sample mean | Average Marginal Effect (AME) | Sample mean | Average Marginal Effect (AME) | Sample mean | |
New studies (August 2015-Feb 2018) | 0.11 (0.13) | 0.32 (0.47) | 0.06 (0.17) | 0.30 (0.46) | 0.05 (0.16) | 0.26 (0.44) |
Research design | ||||||
Difference in Differences (DID) | −0.20** (0.08) | 0.43 (0.50) | −0.20** (0.10) | 0.44 (0.50) | − 0.24** (0.10) | 0.52 (0.51) |
Interrupted Time Series (ITS) | −0.09 (0.10) | 0.12 (0.33) | −0.11 (0.11) | 0.13 (0.34) | −0.67*** (0.08) | 0.09 (0.30) |
Randomized Control Trial (RCT) | −0.19* (0.10) | 0.41 (0.49) | −0.20* (0.11) | 0.10 (0.30) | −0.34*** (0.12) | 0.14 (0.35) |
Country | ||||||
US | −0.11* (0.07) | 0.41 (0.49) | −0.13* (0.07) | 0.41 (0.49) | 0.08 (0.11) | 0.40 (0.50) |
Setting | ||||||
Hospital | 0.06 (0.06) | 0.30 (0.46) | 0.05 (0.07) | 0.32 (0.47) | −0.24** (0.09) | 0.33 (0.48) |
Incentive Schemes | ||||||
Cost and quality | 0.11* (0.06) | 0.25 (0.43) | 0.13* (0.08) | 0.25 (0.44) | −0.34*** (0.08) | 0.21 (0.41) |
Rewards for improvement | −0.12* (0.07) | 0.36 (0.48) | −0.12* (0.07) | 0.38 (0.49) | −0.09 (0.06) | 0.36 (0.49) |
Use of incentives | ||||||
Discretionary use | 0.01 (0.09) | 0.55 (0.50) | ||||
Special use | 0.08 (0.12) | 0.06 (0.25) | ||||
Size of payment to revenue ratio (%) | 0.01* (0.00) | 11.53 (9.18) | ||||
Publication year fixed effects | Yes | Yes | Yes | |||
Number of observations | 116 | 109 | 42 | |||
Number of clusters | 62 | 57 | 25 | |||
Average number of observations per cluster | 1.9 | 1.9 | 1.7 | |||
(Min-Max) | (1–15) | (1–14) | (1–4) | |||
Pseudo-Log | −59.91 | −55.66 | −16.99 | |||
AIC | 1.33 | 1.37 | 1.57 | |||
BIC | − 408.42 | −365.18 | − 84.57 | |||