Table 1.

Summary data from 14 comparative studies of set shifting ability in people with disorders and healthy controls (Roberts et al., 2007) with a classical meta-analysis using an inverse variance weighted average with random effects based on estimated standardized mean differences and a moment estimate of between-study variance (Whitehead and Whitehead, 1991)^†

Study	Effect size (standardized difference in means)	Standard error of effect size
Steinglass	0.38	0.40
Holliday	0.07	0.21
Tchanturia	0.52	0.29
Tchanturia, study 1	0.85	0.25
Tchanturia, study 2	0.45	0.29
Murphy, study 1	0.01	0.35
Murphy, study 2	−0.58	0.36
Mathias and Kent	0.44	0.25
Kingston	0.46	0.22
Thompson	0.93	0.47
Jones, study 1	0.28	0.24
Jones, study 2	0.20	0.28
Jones, study 3	0.46	0.23
Witt	0.59	0.36

^†Test for heterogeneity (equation (7)): Q =16.73, 13 degrees of freedom (P =0.02); I²=22%. Random-effects meta-analysis: standardized mean difference (95% credible interval 0.19–0.53); U^*=4.23 (P =2×10⁻⁵); .