Dear Editor,

We read with great interest the article by Freeman et al. [1] and commend the authors for further investigating the efficacy of abdominal versus laparoscopic sacrocolpopexy. The study design was good and obtained important evidence of the discrepancy between two different routes. However, we feel that the text of “Patients and methods” is flawed in its description of the pelvic organ prolapse quantification (POP-Q) system [2].

The authors state: “Patients referred with symptomatic grade 2 or more post-hysterectomy vaginal vault prolapse (i.e. vaginal angles/“dimples” seen at least 1 cm above or beyond the hymeneal remnants)”. It is apparent that this statement is contradictory. It is well known that grade classification belongs to the Baden–Walker half-way system. Women with grade 2 or more vault prolapse means that their leading portions of prolapse are over the mid-plane of the vagina, while the latter sentence showing “at least 1 cm above or beyond the hymeneal remnants” should equate to stage 3 or more of the POP-Q system. Moreover, the “Inclusion criteria” showed “patients with symptomatic and bothersome vault prolapse of greater than or equal to grade 2 on the POP-Q”. I wonder about the real extent of POP in all the participants in this study.

Over the last decades, the POP-Q system has gained international recognition as the “gold standard” for classifying pelvic support and a number of reports in the literature document excellent intra- and inter-examiner reliability [3]. The Baden–Walker half-way system remains commonly employed in clinical practice because of its ease of use. However, it should not continue to replace the POP-Q system in scientific studies [3].

Although this is simple knowledge in POP, a number of clinical surgeons ignore it. We hope that this letter might remind reviewers or authors to take a look at the discrepancies between the two classification systems.