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. Author manuscript; available in PMC: 2011 Aug 23.
Published in final edited form as: Schizophr Res. 2010 Jun 25;121(1-3):1–14. doi: 10.1016/j.schres.2010.05.033

Meta Analysis Diagnostics

Reality distortion r Type of N Critical N Q statistic p Significant study characteristics Number of Studies dropped for homogeneity r P
Verbal Memory -.01 S 59101 17.35 .36
Visual Memory .01 S 59398 8.13 .62
Working Memory -.00 S 3840748 10.32 .92
Reasoning and Problem solving -.06 FD 485 32.05 .23
Speed of processing -.03 S 3033 67.59 <.01 Gender, Sample Size Bell et al., 1994 .01 .76
Attention -.12 FD 1295 5.61 .85
Combined Category r Type of N Critical N Q statistic p Significant study characteristics Number of Studies dropped for homogeneity r P
Verbal Memory -.07 FD 5493 19.17 .12
Visual Memory -.15 FD 1443 8.42 .39
Working Memory -.06 FD 1895 30.58 <.01 Education Bressi et al., 1996
Pukrop et al., 2003
-.06 .01
Reasoning and Problem solving -.03 S 898 54.44 <.01 (*) Braff et al., 1991
Bryson, Bell, Grieg, 1999
-.01 .47
Speed of processing -.02 S 8439 26.05 .19
Attention .04 FD 187 21.00 .14
Disorganization r Type of N Critical N Q statistic p Significant study characteristics Number of Studies dropped for homogeneity r P
Verbal Memory -.20 FD 22907 45.94 <.01 (*) Eckman and Shean, 2000, Mohamed et al., 1999 -.19 <.01
Visual Memory -.20 FD 9286 27.95 .01 Gender Mohamed et al.,1991 -.23 <.01
Working Memory -.20 FD 7989 20.51 .43
Reasoning and Problem solving -.24 FD 74399 77.03 <.01 Sample Size Franke et al., 1992,
Klingberg, Wittorf, Wiedemann, 2006,
Nestor et al., 1998
-.28 <.01
Speed of processing -.26 FD 101862 64.68 .01 (*) Eckman & Shean, 2000,
Mohamed et al., 1991,
Hofer et al., 2007
-.25 <.01
Attention -.25 FD 31184 40.32 <.01 (*) Mohamed et al., 1999 -.27 <.01

Note: 1) Only 2 studies were outliers in more than one of the neurocognitive domains: Eckman and Shean, 2000 (2 domains) and Mohamed et al., 1999 (4 domains) whereas all other studies showed discrepancies only in one domain. 2) for Type of N, S = number of studies with the same effect size required to get a significant result and FD = number of unpublished studies with an r of 0 required to make this result not significant (file drawer problem). 3) for Significant Study Characteristics an (*) indicates that study heterogeneity was not associated with any of the study parameters.