The psychopathology of everyday art: a quantitative Study - World ...

to no acceptable answers but conclude with calls for further research. This literature,
despite its heavy emphasis on qualitative reports, is an appropriate candidate for meta-
analysis.
Meta analysis is the application of statistical procedures to collections of
empirical findings from individual studies for the purpose of integrating, synthesizing and
making sense of them. A common metric aggregates diverse statistics across studies, and
standardised methods help to produce an unbiased assessment of the reliability of a
variable measured across studies. It addresses five methodological difficulties which have
been identified with traditional literature reviews 212
(1) selective inclusion of studies often based on the reviewer's impressionistic view of the
quality of the study;
(2) differential subjective weighting of studies in the interpretation of a set of findings;
(3) misleading interpretations of study findings;
(4) failure to examine characteristics of the studies as potential explanations for disparate
or consistent results across studies;
(5) failure to examine moderating variables in the relationship.
Selection of studies for Meta-analysis
The first criterion for analysis of absolute differences between groups was that terms
should be reliable. From the pool of 51 controlled studies, 35 employed no assessment
or indication of reliability, therefore any bias would be overwhelming. Because weighting
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Summarised by Frederic M. Wolf (1986), Meta Analysis: quantitative methods for research synthesis ,
Beverley Hills, CA: Sage, p.10.
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