ABSTRACT
Child-centered play therapy (CCPT) research spans over 60 years, providing evidence of effectiveness across a diversity of generations, ages, ethnicities, settings, and presenting problems. Between the years of 1947 and early 2010, 63 studies were conducted on the effectiveness of CCPT. In this chapter, the author details a lengthy description categorizing 62 CCPT studies by research issue and standard of rigor. Using A. Rubin’s conceptual framework, the author applied his evidentiary hierarchy for evidence-based practice to the identification of individual research studies. Specifically, studies are categorized into three labels: experimental, quasi-experimental, and evidentiary. The experimental label describes studies meeting the most stringent criteria for research design, including random assignment of subjects, comparison to a control group or another treatment group, clear methodology and treatment descriptions, and attention to internal and external validity threats. The quasi-experimental label represents studies that used comparison or control groups with clear methodology and attention to internal and external validity threats but not random assignment.
