Conclusion
The results of this scoping review highlight that nonadherence to the medication among patients with MDD is a major obstacle in reducing public health challenges in both developed and developing countries. The evidence shows that patients with MDD have a high rate of medication nonadherence. However, accurate assessments of medication adherence will provide better evidence on the outcomes, risk factors, and interventions to improve medication adherence. Numerous measurements available for assessments of medication adherence, also need to prove to be valid, reliable, and sensitive. However, the selection of measurements should be based on researcher or healthcare professionals’ attributes, goals, resources of the clinical setting, or study. Although, none of the measurements can be considered as a gold standard, and the triangulation of measures is recommended. The behaviors of taking mediation are often faced multi-factorial causes, identify of it important to implement appropriate medication adherence enhancing interventions. Also, interventions require several components to focus on these factors, and health care professionals must follow a systematic process to assess possible factors.