Review for 10.1186/s12876-023-02929-7 (2023)

Title: Efficacy of washed microbiota transplantation for therapeutic targets of refractory
functional constipation and the influencing factors: A single-center, retrospective, 24-week
follow-up study
Version: 1 Date: 10 Apr 2023
Reviewer's report:
In the manuscript, to analyze the efficacy of WMT and the potential factors that might affect the
efficacy, the authors performed a retrospective analysis of 24-week follow-up data of 63 patients
with refractory constipation who received 112 WMT courses. The primary outcomes of this
study were improvement rates for individual treatment targets, and secondary outcomes were
clinical response rates, clinical improvement rates, stool frequency, Wexner constipation score,
Bristol Stool Form Scale scores, and adverse events. Based on observation and comparison
of the primary and secondary outcomes before WMT and 4,8,24 weeks after WMT, it turned
out that WMT treatment significantly improved FC-related treatment goals, especially the
reduction of straining, hard stools, and stool frequency at weeks 4, 8, and 24 after treatment,
and the improvement rate and overall remission rate were the highest at week 8. In addition,
the univariate and multivariate analyses revealed that the history of using defecation drugs and
the course of WMT were significantly associated with improving one of the therapeutic targets,
and the overall response at weeks 4, 8, and 24. This study contains some interesting findings
and is valuable for insight into a novel treatment for refractory constipation and the potential
influencing factors for WMT’s efficacy. However, some problems need to be addressed.
Comments#
1 There are some mistakes in English grammar and expressions. The language of the whole
manuscript needs to be carefully checked and polished.
2. Why did you choose 4, 8, and 24 weeks as observation points? Are there any supporting
references?
3. Could you explain the lack of statistical correlation between Wexner's constipation score and
therapeutic targets in Table 2?
4. The Introduction Part is a little tedious and it should be more concise.
5. The exclusion criteria: were the patients with constipation secondary to some drugs, abuse
history, endocrine, or autoimmune diseases excluded? It should be clarified.
6. Statistical analysis
(1) “To compare differences in continuous variables between groups, a t-test was performed”.
Were all the continuous data normally distributed? If continuous variables are non-normally
distributed, a rank-sum test was recommended.
(2) “Parameters with a P<0.1 were included in multivariate logistic regression analysis using a
logistic regression method to identify independent factors”. Some parameters with Ps>0.1 could
be associated with WMT efficacy in terms of clinical significance or previous findings. It is
suggested to include these parameters in your logistic regression analysis.
7. Figure 1A: The proportions of patients concerning five therapeutic targets all decreased at
week 4, 8, and 24 compared to week 0. Did all these decreases have statistical significance and
which indicators improved most? Is there any significant difference in the rates among different
follow-up time points? These issues should be addressed in detail in your manuscript.
8. Why did you define the clinical remission rate and the clinical improvement rate by SCBMs?
Are there any related references?
9. “The proportions of patients with BSFS score 1 and 2, indicating constipation, significantly
decreased from 52.4% vs 39.7% pre-WMT to 6.3% and 36.5%, respectively, at week 4 post-
WMT”. Is there any significant difference between week 0 and week 4? What are the P values?
10. Secondary outcomes were presented in logistic regression but in the univariate analysis, we
found no associations were performed between secondary outcomes and baseline characteristics.
Could you explain it?