Similarities and differences between study designs in short- and long-term outcomes of laparoscopic versus open low anterior resection for rectal cancer: A systematic review and meta-analysis of randomized, case-matched, and cohort studies.

Findings from case-matched studies were similar to those from RCT in laparoscopic low anterior resection for rectal cancer. However, findings from case-matched studies were sometimes intermediate between those of RCT and unadjusted cohort studies, and case-matched studies and cohort studies have a potential to overestimate the treatment effect compared with RCT.