Pearls of meta-analyses and systematic review in scientific evidence.

Scientific evidence develops bit by bit from case reports, case series; to larger case-control, case-cohort; and further escalate to randomized controlled trials. This echoed the importance of continue publishing , where novel and advancing discoveries start from a single case. In contrast, at the other end of the realm of evidence synthesis, systematic review and meta-analysis represent distinct yet interconnected processes. Butorphanol in epidural labor analgesia has long been studied since 1989, and with 70 publications from MEDLINE searches. However, there was no meta-analysis, nor any systematic review published so far. The latest in-press article published by Tang on the protocol for the systematic review and meta-analysis on the safety and effectiveness of butorphanol in epidural labor analgesia is encouraging. We believe the findings of this study will be valuable for clinical practice as well as for future research.