LAUSR

We thank Gachabayov and colleagues for their letter commenting on the article by Trenti et al. [1] published in Techniques in Coloproctology. We are sorry if some statements and results confuse the reader. We are happy to clarify all the points highlighted in the letter. Some of them may have resulted from perfunctory reading of the article. As regards the design of the study, we did not define it as prospective. As stated in the Materials and methods, it is a longitudinal study comparing two cohorts of patients. The fact that data were prospectively collected in a clinical database does not mean that the design of the study is also prospective since the question for the analysis is posed at the time of the study and not prior to the collection of data. We agree with the comment that a selection bias may exist in relation to assignment of patients to THD Doppler procedure or conventional excisional hemorrhoidectomy. This is due to the design of the study and could only be controlled in a randomized trial setting. We understand that the fact that all the THD procedures were performed by the same surgeon is a potential bias. However, it could be argued that expertise in both groups is balanced since the THD group is favored by a single surgeon performing while conventional hemorrhoidectomy benefits from experience over time with a classic technique. On the other hand, while in the THD group the operator had to deal with the difficulties of a novel operation, in the conventional group there were several experienced surgeons operating. Regarding the score designed by Giordano [2] measuring the frequency of hemorrhoid symptoms, we agree with the authors that it has not been validated yet, but we think that it is complementary tool to the Goligher classification. The score makes it possible to compare hemorrhoid symptoms and frequency before and after surgery. Moreover, contrary to what Gachabayov and colleagues state in their letter, the score has been used in at least two published papers that include patients with grade 4 hemorrhoids [3, 4]. We agree that the terms persistence and recurrence should have been better clarified. It might be helpful if both terms were used in the title of Table 5. Quite frequently, some symptoms may persist after surgery but improve with time. Sometimes, there may be recurrence. In any case, any symptoms, persistent or recurrent, were collected and reported. For the purposes of our paper, symptoms after surgery (either persistent or recurrent) help to compare efficacy of technique. In response to the criticism of Table 4, it is well known that the SD can be higher than the mean. The range of numbers has to be large for this to occur and in no way implies that the values have to be negative as the authors point out with unveiled sarcasm. As for the semantic issue regarding ‘‘differential mean,’’ perhaps Table 4 is not clear enough. We inserted ‘‘mean (SD)’’ beside both ‘‘Total score’’ and ‘‘Differential.’’ Maybe this caused confusion, since the authors thought this was a mislabeling for mean difference or difference in means. We could have put ‘‘mean (SD)’’ on a different line. However, the meaning of ‘‘Differential’’ is clearly stated in the table legend. & S. Biondo [email protected]