The Use of Behavior Change Theories in Dietetics Practice in Primary Health Care: A Systematic Review of Randomized Controlled Trials

Background Behavior change theories frameworks provide the theoretical underpin- ning for effective health care. The extent to which they are applied in contemporary dietetics interventions has not been explored. Objective To systematically review the evidence of behavior change theory -based in- terventions delivered by credentialed nutrition and dietetics practitioners in primary health care settings. Methods Medline, the Cumulative Index to Nursing and Allied Health Literature, Psy- cINFO, Embase, and Cochrane databases were searched for English language, randomized controlled trials before August 2019. Preferred Reporting Items for Systematic Reviews and Meta -Analysis guidelines were followed. Eligible interventions included adults (aged 18 years) receiving face-to-face dietetics care underpinned by behavior change theories in primary health care settings with outcome measures targeting changes in health be- haviors or health outcomes. Screening was conducted independently in duplicate and data were extracted using prede fined categories. The quality of each study was assessed using the Cochrane Risk of Bias tool. The body of evidence was assessed using the Academy of Nutrition and Dietetics Evidence Analysis Manual Conclusion Grading Table. Results Thirty articles reporting on 19 randomized controlled trials met the eligibility criteria, representing 5,172 adults. Thirteen studies (68%) showed signi ficant improve- ments for the primary outcome measured. Social cognitive theory was the behavior change theory most commonly applied in interventions (n=15) with 11 finding sig- ni ficant intervention effects. Goal setting, problem solving, social support, and self - monitoring were the most commonly reported techniques (n=15, n=14, n=11, and n=11, respectively). Most studies had a high (n=11) or unclear (n=8) risk of bias. There was fair evidence (Grade II) supporting the use of behavior change theories to inform development of dietetics interventions. Conclusions Interventions delivered by credentialed nutrition and dietetics practi- tioners that were underpinned by behavior change theories and utilizing various behavior change techniques were found to have potential to be more effective at improving patient health outcomes than dietary interventions without theoretical un- derpinnings. Findings from this review should inform future primary health care research in the area of dietary behavior change. In addition, findings from this review highlight the need for stronger documentation of use of behavior change theory and techniques that map on to the theory within dietetics practice.