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

The studies are difficult to sum up collectively in any meaningful way as each
study examines a different selection of qualities, which makes them difficult to compare
or replicate and the final interpretation comes as a synthesis of the study. Some of the
definitions seem unclear, especially those which deal with global categories and some
studies dealing with objective qualities provide a huge unwieldy instrument where
alternative terms are difficult to differentiate 201 . Most conspicuously, there are
considerable problems as to the authors' use of statistics (which will be discussed next).
Mostly, the statistical bases on which the reliability is calculated contain serious
methodological flaws.
Measures of agreement
Agreement between categorical assessments compares the ability of different raters to
classify subjects into one of several groups. The reason studies use 2 or more raters is
usually to see if the raters agree well enough for one to replace another or for raters to be
used interchangeably. One consideration which would improve the quality of some of the
studies reported here would be the definition of what is meant by agreement, also the
degree of agreement.
Most reported measures of reliability gave an 'overall agreement' statistic, which
took the mean of the summed agreement percentages for each element. It is not possible,
of course, in many cases, to measure these quantities directly and the decision on what
constitutes good enough agreement must lie with the clinical conditions. However, 6
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W.L. Wadlington and H.J. McWhinnie (1973) The development of a rating scale for the study of formal
aesthetic qualities in the paintings of mental patients, Arts in Psychotherapy , V.1(3-4):210-20.
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