What is the effectiveness of various invitation methods to a colonoscopy in the early detection and prevention of colorectal cancer? Protocol of a systematic review

BACKGROUND: Colorectal cancer, a prevalent malignancy worldwide, is associated with numerous modifiable and non-modifiable risk factors that play a role in the early detection and successful treatment of cancer. Despite improvements in the availability and quality of screening methods, especially colonoscopy, and the substantial survival benefits of the early detection of colorectal cancer, patient participation remains low due to clinical reasons and patient barriers. Studies around the world have used various methods of invitation in order to promote patient uptake of colonoscopies. The main objective of this systematic review is to analyze the association between certain invitation procedures, the participation in colonoscopies, and important patient outcomes in the early detection and prevention of colorectal cancer. METHOD: We will systematically search in electronic databases including Medline via PubMed and Ovid, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and the Cochrane Library. All studies will be described in a table of study characteristics with a risk of bias assessment. In addition, two authors will independently rate the overall quality of evidence for the critical outcomes using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group approach. Discrepancies regarding the inclusion of studies, data extraction, or risk of bias assessment will be resolved independently by one other reviewer. Due to the heterogeneous design of the studies that will be evaluated in this review, synthesizing data from these studies in the form of a meta-analysis may not be possible. In this instance, we can conduct a descriptive synthesis of data from these studies. DISCUSSION: The results that arise from this systematic review will reflect the influence that various invitation procedures to a colonoscopy have on patient participation in these screenings. Drawing conclusions about the efficiency of various invitation methods to a colonoscopy can provide valuable information to both clinicians and patients and may not only improve future invitation-based patient recruitment to colonoscopy screenings, but also shape guidelines regarding prevention of colorectal cancer. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019128645