Single-Incision Versus Conventional Three-Incision Laparoscopic Appendectomy: A Single-Center Experience

Dear Editor:

We read with great interest the article by Amos et al. ¹ in which the authors compared the short-term outcomes of single-incision and conventional three-incision laparoscopic appendectomy at a single surgical unit. The article indicated that the time to resume oral intake was slightly less in the single-incision group than that in the three-incision group (P=.0419) and that the blood loss and length of hospital stay were comparable between the two groups (P>.05). We agree with their conclusion that the single-incision laparoscopic appendectomy has benefit in cosmetic outcomes, due to the well-concealed scar, ¹ and their viewpoints have been confirmed by other studies,^2–6 especially for nonobese patients. ²

However, we found a statistical error in the article that may affect the final conclusion. The authors stated that the time to oral intake was shorter in the single-incision group than that in the three-incision group (P=.0419), ¹ although comparable length of time to oral intake was reported in another randomized controlled trial. ³ However, according to the data they provided, we detected unequal variances of the data (F=3.3481, P=.0061); thus the t’ test should be applied for the statistical analysis. When this is applied, the result is that there was no significant difference in the time to oral intake between the two groups (t’=1.8474, P>.05), which will raise a question about their calculation of faster recovery in the single-incision group, and, accordingly, the conclusion of the article will be changed. Moreover, the wrong data may mislead our meta-analysis of single-incision versus conventional three-incision laparoscopic appendectomy. We would like to share this information with the authors.