Limitations of Randomized Control Designs in Psychotherapy Research

Glenn Shean

doi:10.1155/2014/561452

Abstract

Despite the growing influence of lists of empirically supported therapies (ESTs) there are concerns about the design and conduct of this body of research. These concerns include limitations inherent in the requirements of randomized control trials (RCTs) that favor those psychotherapies that define problems and outcome in terms of uncomplicated symptoms. Additional concerns have to do with criteria for patient selection, lack of integration with research on psychotherapy process and effectiveness studies, limited outcome criteria, and lack of controls for experimenter bias. RCT designs have an important place in outcome research; however it is important to recognize that these designs also place restrictions on what and how psychotherapy can be studied. There is a need for large scale psychotherapy outcome research based on designs that allow for inclusion of process variables and the study of the effects of those idiographic approaches to therapy that do not lend themselves to RCT designs. Interpretative phenomenological analysis may provide a useful method for the evaluation of the effectiveness of idiographic approaches to psychotherapy where outcome is not understood solely in terms of symptom reduction.

Highlights

There are several issues related to the external validity of lists of empirically supported psychotherapies (ESTs) that should be considered before broad policy changes are instituted based on this body of research
The design requirements of randomized control trial (RCT) studies do not allow for adequate understanding of the multifaceted nature of many mental health problems or the complex interplay of individual differences, interpersonal processes, and range of potential outcomes that are inherent in psychotherapy practice
A white paper issued by a Task Force of the American Psychological Association in 1995 stated that “in order to remain competitive in the mental health services marketplace psychologists must provide evidence of therapeutic efficacy in the form of lists of empirically supported psychotherapies (ESTs) for specific disorders” [4]

Summary

Introduction

There are several issues related to the external validity of lists of empirically supported psychotherapies (ESTs) that should be considered before broad policy changes are instituted based on this body of research. The design requirements of randomized control trial (RCT) studies do not allow for adequate understanding of the multifaceted nature of many mental health problems or the complex interplay of individual differences, interpersonal processes, and range of potential outcomes that are inherent in psychotherapy practice. The EST literature is based on studies characterized by unacknowledged sampling issues, methodological constraints, researcher bias, and limited outcome criteria [1,2,3]

Background

Issues Related to ESTs

Findings

Conclusion