Use of Theory in Behavior Change Interventions

Area of Science:

• Behavioral science
• Public health
• Cancer survivorship

Background:

• Theory-based behavioral interventions are crucial for enhancing physical activity in breast cancer survivors.
• However, the extent to which theory is applied in these interventions and its impact on effectiveness remain under-examined.

Purpose of the Study:

• To evaluate the intensity of theory application in physical activity interventions for breast cancer survivors.
• To determine if the extensiveness of theory use is associated with intervention effectiveness.

Main Methods:

• A systematic search identified randomized controlled trials (2005-2013) focusing on physical activity behavior change in breast cancer survivors within 5 years post-treatment.
• Theory application intensity was calculated using eight items from Michie and Prestwich's coding framework.
• Studies were categorized into sparse, moderate, and extensive theory use levels.

Main Results:

• Fourteen trials met the inclusion criteria, with the Transtheoretical Model and Social Cognitive Theory being most frequently applied.
• Five studies were classified as Level 1 (sparse), four as Level 2 (moderate), and five as Level 3 (extensive) in theory use.
• The extensive theory use group (Level 3) demonstrated the largest overall effect size (g = 0.76), compared to Level 1 (g = 0.28) and Level 2 (g = 0.36).

Conclusions:

• While theory application in behavioral interventions varies, this study provides evidence that more extensive use of theory may enhance intervention effectiveness for breast cancer survivors.
• Further investigation is warranted to fully understand and optimize the role of theory in improving physical activity interventions for this population.