Title: Molecular diagnosis of Trichomonas vaginalis in liquid-based Papanicolaou samples in
Shiraz, southern Iran
Version: 1 Date: 14 Aug 2022
Reviewer's report:
Manuscript ID: f128d217-a69c-47e1-851d-e44de35d58ce
Manuscript title: Molecular diagnosis of Trichomonas vaginalis in liquid based Papanicolaou
samples in Shiraz, southern Iran
This is an original research study that investigates investigate the molecular diagnosis of
Trichomonas vaginalis infection in liquid based Papanicolaou samples in Shiraz, southern Iran.
The study further investigates the potential sociodemographic and clinical factors associated
with T. vaginalis infection in the studied population. The authors clearly outline the aim of
the study, study design and methodology. However, the results and discussion sections would
benefit from some revision. Therefore, if this research paper meets the requirements of the
journal after revision, it can be recommended for publication.
Please see comments below.
MAJOR ISSUES:
Background:
• Line 49-51: “Trichomoniasis is caused by the protozoan Trichomonas vaginalis, is one of the
most common sexually transmitted diseases (STD), with an estimated annual incidence of 276.4
million cases globally [1-3].”
• The authors cite references 1-3 for this statement. However, it is not possible for these
references to have this information “with an estimated annual incidence of 276.4 million cases
globally” as they were published before these estimates were available. The annual incidence
of 276.4 million cases was published in 2012 by “World Health Organization (2012) Global
Incidence and Prevalence of Selected Curable Sexually Transmitted Infections - 2008. WHO,
Geneva”.
• Please correct this issue.
• Line 53-54: please include complications in women. Since the article is conducted in female
subjects, I believe it is appropriate to include complications of TV infection in women as well.
• Line 56-57: “The prevalence of T. vaginalis infection have been reported differently in various
regions and populations of Iran [7].”
• What do the authors mean by “differently”? Does this mean the differences in diagnostic
techniques and study populations among these studies? Or it means varying TV infection
prevalence rates?
Materials and Methods:
• Line 84: please elaborate on “burning”. Is it burning during urination (dysuria)?
• Line 89: please add in the marketing name of the kit used.
• Line 91: please add in the marketing name of the “2 × red PCR premix”.
Results:
• Line 108-109: “Out of 534 participants, 494 (92.5%) were married, 7 (1.33%) were single and
33 (6.17%) were divorced.”
• please be consistent with the use of decimal points. This should be checked and corrected
throughout the manuscript.
• Line 110-111: “The highest frequency (197/534; 36.9%) belonged to people with bachelor's
degrees.”
• Please rephase this statement. Suggestion: The majority of the women (197/534; 36.9%) had
a bachelor’s degree as their highest level of education.
• Line 113: “The manifestations which can be related to trichomoniasis including the history of
abortion, preterm birth delivery, …”
• Please rephrase this line, history of abortion and preterm delivery are not manifestations.
• Line 114: please be consistent with the use of words or terms. The authors used itching in the
data collection section and in this section, they use “pruritus”. Please correct this.
• Line 114: “pruritus, burning, urinary frequency”. Please list these as they are in Table 1.
• Line 119-121: Please include the percentages of the women who had and did not have foamy
and foul-smelling discharge.
Table 1:
• Please arrange the characteristics in the order they are stated in the text of the results section
for easy following. Alternatively, the authors can group the characteristics as sociodemographic
(age, marital status, education level, residential area), behavioral (number of sexual partners)
and clinical (history of abortion, premature birth, foamy and foul-smelling discharge, itching,
burning and frequent urination, pain during intercourse).
• Can the authors caption column 2 (Frequency No (%)) as “overall n (%)” or any way that will
reflect that those are the stats for the entire study population?
Discussion:
Overall, the discussion section requires some revision in terms of structuring the sentences and
paragraphs. A short introduction at the beginning of the discussion would be nice. The authors
need to also compare their findings with other studies that used liquid-based Pap samples for
TV infection diagnosis. In addition, the authors can discuss whether liquid-based Pap smear
specimens have been shown to be best for TV infection diagnosis during routine screening. Age
was shown to be associated with TV infection; however, the authors did not discuss this finding.
• Line 125-126: “The overall prevalence of T. vaginalis infection in the Iranian population was
0.4% to 42%”.
• In which year?
• Please rephrase this statement to show that these prevalence rates are reported by previous
studies.
• Line 126-129: how do the findings of Haghighi et al., (2019) differ from your findings? Which
factors maybe be causing these differences?
• Line 131-134: this information was copied and pasted directly from the abstract section of the
referenced article. Please write this information in your own words.
•  Line 136-137: “…could be due to the target populations”. This is not the only factor
responsible for the different prevalence rates. I believe, type of specimen collected, and
diagnostic techniques are also contributing factors.
• Line 148-150: “Consistent with our results in studies that used Pap smears of to detect T.
vaginalis, the prevalence was usually less than 5% and 21 to 30 years of age as high-risk years
[22].”
• The referenced study did not use Pap smear samples to detect TV infection. The authors from
the referenced study used or collected vaginal swabs.
• Line 154: ‘(95% CI, 2. 0.08)”. Please correct the confidence interval.
• Line 156-159: this statement is out of place. The authors introduced this paragraph as a
discussion on the association between abnormal vaginal discharge and TV infection. However,
this statement does not discuss this.
MINOR ISSUES:
Minor issues have been highlighted in the manuscript document using track changes mode.
Abstract:
• Line 36: please rephase “26 samples (26/534; 4.86%)” to 4.86% (26/534).