Some problems of quantitative analysis of data in psychotherapy research

The aim of the study is to refer to some problems of quantitative analysis of data in psychotherapy research. A special attention is paid to problems of effect of psychotherapy assessment, i.e. the magnitude of effect, meta-analysis comparing different studies in measurement of effect of different psychotherapies, problems of intervening variables in effect research, clinical significance of measured findings, problems connected with using the null hypothesis and others. The author also deals with some sometimes forgotten features of this type of data evaluation. The study also aims at problems of employing the quantitative analysis of data in psychotherapeutic process research, more specifically at problems in using the rating scales and their quantitative evaluation. The study should represent a contribution to using the quantitative data processing with a broader comprehension of the context of this type of data evaluation.