Evidence-Based Practice in Psychology: Context, Guidelines, and Action

A science-based approach to understanding health and disease emerged gradually over the past two centuries, while the modern evidence-based approach to health care emerged only about a half-century ago. The evidence-based approach to practice in health service psychology (HSP) gained significant traction after the American Psychological Association (APA) adopted it as policy in 2005, and in 2021, APA approved the first comprehensive set of guidelines for practicing HSP in an evidence-based manner. Several authors of this 2021 set of guidelines along with an additional subject matter expert wrote the current article. This article outlines the development of evidence-based practice in psychology, discusses the strengths and weaknesses of each of the three components of evidence-based practice (i.e., best available research, clinical expertise, and patient characteristics, culture, and preferences), and highlights the complexity involved in integrating related considerations during clinical decision making. The article then discusses strategies for the systematic application of this approach in HSP to improve the effectiveness of behavioral health care and strengthen population health.