→First author, publication year, country of origin, reason for exclusion, and type of study were extracted for each study, and the following data for each arm: Goligher grade, route of administration of sclerotherapy (i.e., anoscopic or endoscopic), type of sclerosing agent, type of needle, method of formation of the injected product, site(s) of injection, injected volume (total and per pile), patient position, anesthesia, study length (months), number of patients, number of male patients, mean or median age, mean injection time, intra- and postoperative complications, pain, success rate (overall and after the first injection), recurrence rate, follow-up (months), and scoring system(s).