1. Studies must include empirical research
2. Studies must be published in English
3. Studies must be published in a peer reviewed journal
4. Studies must report treating clinician attitudes towards CPGs for active cancer treatment or perceptions of barriers or facilitators to adherence to those CPGs.
Articles not including empirical research were excluded. Studies reporting on CPGs that focused on other aspects of cancer care (such as screening, psychosocial care, palliative care, or symptom management CPGs) were excluded.