A Systematic Review of the Effectiveness of Play Therapy

Background/Rationale:  This paper details a systematic review (SR) of the effectiveness of individual play therapy for school age children.  Social workers are key providers of play therapy (Webb, 2011).  Play therapy can be a means to improve interpersonal functioning and to reduce dysregulation and violence.  The few available play therapy SRs have been written by scholars who are also the authors or instructors of many of the included studies, raising concerns of attribution bias and conflicts of interest (Bratton, & Swan, 2017; Ray, Armstrong, Balkin, & Jayne, 2015).  Some prior reviews also mix different modalities and models of play therapy.  This SR seeks to add rigor and detail to knowledge about the effectiveness of individual play therapy and to point out how this knowledge may be applied to social work research, education and practice.

Methods:   A systematic review of individual play therapy effectiveness was completed, guided by Cochrane Collaboration guidelines (Higgins & Greene, 2011).  The team searched for the terms “play therapy,” “play psychotherapy,” and “experiment*,” “RCT*,” “child*,” “effectiveness,” “outcomes,” and “efficacy”– both separately and in combination.  The CINAHL Plus data base yielded 914 citations, PubMed yielded 2,257 citations, PsychInfo yielded 2,209 citations, and Social Work Abstracts yielded 105 citations.  From these 5,485 publications the team reviewed abstracts to determine irrelevant or redundant publications.  In addition, a ‘pearl growing’ technique was applied to identify additional literature using citations from relevant articles and books of play therapy from the past 10 years.  Ninety-six publications were reviewed by at least two team members.  A total of 32 publications proved relevant and met quality and inclusion standards (an RCT using a clearly defined play therapy and providing pre- and post- means and standard deviations). (A quorum chart will be provided.)

Results:  A meta-analysis was completed using Cohen’s d for samples of 50 or greater and Hedges g for smaller samples. Play therapy generally demonstrated small to moderate effect sizes overall (from d = .21 to d = .80), indicating it is generally an effective intervention under current SR and meta-analytic standards.  These effect sizes are somewhat smaller than those reported in prior reviews.  In addition, the types of problems addressed using play therapy were identified, along with populations and settings in which rigorous research is limited. Effect sizes varied for different client problems and sometimes as measured by different standardized measures. Overall, several models of play therapy had empirically demonstrated effectiveness.

Conclusion/Implications:   Play therapy is a research supported therapy warranting inclusion in social work practice and educational curricula.  Play fits well with a range of child service needs and developmental considerations, but has not been studied with several diagnoses.  Several models of play therapy are found in the literature; many could benefit from greater detail or treatment manuals.  Outcome measures employed varied widely; a combination of symptom specific and omnibus measures would provide a more compete assessment of outcomes.  Additional outcome research on play therapy should be undertaken, including larger samples and including more diverse clients.