Comparison of dose and injection sites of botulinum toxin for chronic anal fissure: a systematic review and network meta-analysis of randomized controlled trials.

- Vitoopinyoparb, Kasidin; Insin, Putsarat; Thadanipon, Kunlawat; Rattanasiri, Sasivimol; Attia, John; McKay, Gareth; Thakkinstian, Ammarin