Table 3.
Subgroup analysis of effect sizes by publication type.
| Publication type | k | SMD (95% CI) | Weight, % | 95% CI | 95% CI | I2, 100% |
|---|---|---|---|---|---|---|
| Lower | Upper | |||||
| Conference paper (Ref) | 3 | 0.373 | 11.5 | 0.015 | 0.732 | 89.90% |
| Journal article | 15 | 0.338 | 57.7 | −0.027 | 0.703 | |
| Dissertation | 8 | 0.2 | 30.8 | −0.231 | 0.631 |
Test for subgroup differences (Between-group heterogeneity): χ2 = 1.03, df = 2, p = 0.596. k, number of studies; SMD, Standardized Mean Difference; CI, Confidence Interval; I2, measure of heterogeneity; Ref, Reference group.