Predicting Stage of Exercise Among Patients with Type 2 Diabetes: A Test of the Extended Theory of Planned Behavior

Abstract

Purpose

This study aimed to predict stage of exercise among Chinese patients with type 2 diabetes by using an extended theory of planned behavior model (TPB) incorporating descriptive norm and self-identity.

Patients and Methods

Participants (N=791) were included in a cross-sectional study. Structural equation modeling was used to explain how the extended TPB could predict the stage of exercise.

Results

The model accounted for 41% of the variance in stage of exercise and 81.1% of the variance in intention. Intention (β=0.359, P<0.01) and self-identity (β=0.236, P<0.001) had a direct effect on stage of exercise. Self-identity (β=0.261, P<0.001), descriptive norm (β=0.035, P<0.05) and PBC (β=0.683, P<0.001) were strong predicators of intention. The effects of self-identity and PBC on behavior were significantly mediated via intention. Age, BMI and stage of diet behavior were found to be significantly related to intention and behavior.

Conclusion

This study has tested the usefulness of the extended TPB for explaining exercise in Chinese diabetic patients. To promote patients to start or continue exercising, interventions should target self-identity and controllability for physical activity.

Keywords:

• theory of planned behavior
• stage of change
• exercise
• descriptive norm
• self-identity

Abbreviations

TPB, theory of planned behavior model; SOC, stage of change; PBC, perceived behavior control; χ²/df, chi-square divided by degrees of freedom; RMSEA, root mean squared error of approximation; CFI, comparative fit index; TLI, Tucker-Lewis Index; WRMR, Weighted Root mean Square Residual.

Acknowledgments

The authors would like to thank all primary physicians in our program for their supportive help and contribution.

Author Contributions

Min Gao designed the study and wrote the article. All authors contributed to data analysis, drafting or revising the article, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Funding

This research was funded by the National Natural Science Foundation of China (Project No. 71673009).

Disclosure

The authors report no conflicts of interest in this work.