Title: Translation and measurement properties of the pelvic floor distress inventory-short form
(PFDI-20) in Iranian reproductive age women
Version: 0 Date: 10 Mar 2023
Reviewer's report:
Thanks for opportunity to review the paper. It was an important topic with useful evidence for
clinicians in women's health field. The overall quality is acceptable.
- I suggest authors read and add the two references below:
Arruda GT, Henrique TS, Virtuoso JF. Pelvic floor distress inventory (PFDI)—systematic
review of measurement properties. Int Urogynecol J. 2021;32(10):2657-2669. Doi: 10.1007/
s00192-021-04748-4
Mokkink LB, Prinsen CAC, Bouter LM, Vet HCW de, Terwee CB. The COnsensus-based
Standards for the selection of health Measurement INstruments (COSMIN) and how to select
an outcome measurement instrument. Brazilian J Phys Ther. 2016;20:105–13.
Title and abstract:
- I suggest authors use COSMIN terminology for measurement properties throughout the
text. Including, in the title, changing "psychometric properties" to "measurement properties".
(Mokkink LB, Prinsen CAC, Bouter LM, Vet HCW de, Terwee CB. The COnsensus-based
Standards for the selection of health Measurement INstruments (COSMIN) and how to select
an outcome measurement instrument. Brazilian J Phys Ther. 2016;20:105–13)
- The study performs test-retest reliability analysis (2 measurements). Therefore, this study
cannot be characterized as cross-sectional.
- Page 2, line 12: Please change "construct validity" to "structural validity" as per COSMIN
terminology. Apply this throughout the text.
- The correct abbreviation for the Colorectal-Anal Distress Inventory-8 subscale is CRADI-8.
Background:
- In the introduction, there are 34 studies cited. I suggest reducing the number of citations,
according to the journal's rules.
- Please review the acronyms throughout the text. Some acronyms (e.g., PFD) appear without
identification.
- Some words had their abbreviations presented previously, but were again written in full (e.g.,
urine or fecal incontinence)
Methods:
- Page 6, line 11: This study cannot be characterized as cross-sectional.
- Page 7, line 15: Please provide more information about the sample. How was the invitation
made? What was the average age? Did they have a diagnosis of PFD?
- Please define all displayed measurement properties according to COSMIN.
- Page 8, line 6: Please report more information about the sample.
- Page 8: How were the qualitative study interviews analyzed? Was it individual or focus group
interviews? Were the interviewers trained for the interviews? Were the interviews recorded and
the audio transcribed in verbatim? Was there an interview script?
- Page 8, line 11 and 18. Page 10, line 20: Acronyms CVR, CVI and BMI were not presented
in the text. Also, review EFA, CFA…
- Page 9, line 22: I suggest changing the subtitle "Construct validity" to "Population and sample".
- Page 10, line 7: Please explain why women having sex were included.
- Page 11: Please have a look at the systematic review by Arruda et al. (2021) and present the
measurement properties of the PFDI-20.
- Page 12, line 13: How was the retest sample selected?
- Page 12, reliability: Were the participants stable? Did they receive any treatment between the
test and retest? If yes, how was it evaluated? Were the assessments carried out under the same
conditions (role, same evaluator, same environment...)?
- Page 12, line 14: Please describe the type of ICC used.
Page 13, line 1-8: Please insert all statistical analysis mentioned above under the subheading
"Statistical analysis".
Results:
- I suggest adding the translated PFDI-20 as supplementary material.
- Page 13, line 11: Please report the maximum and minimum age of participants.
- Page 14, line 3: Table 3 is not required. The data has already been presented to the text.
- Table 4: Item 6 had a factor loading below the cutoff <0.3. How do the authors explain this?
Is there a need to adjust the model or delete the item?
- Page 14, line 14: Table 6 is not required. The data has already been presented to the text.
Discussion:
- Please discuss the content validity results.
- Page 15, line 7 and 22: The terms "PROM" and “COSMIN” should appear in the introduction.
- Page 16, line 1-5: Please compare your results with studies that presented other structures:
(1) Barber MD, Kuchibhatla MN, Pieper CF, Bump RC. Psychometric evaluation of 2
comprehensive condition-specific quality of life instruments for women with pelvic floor
disorders. Am J Obstet Gynecol. 2001;185(6):1388-95;
(2) Ma Y, Xu T, Zhang Y, Mao M, Kang J, Zhu L. Validation of the Chinese version of the Pelvic
Floor Distress Inventory-20 (PFDI-20) according to the COSMIN checklist. Int Urogynecol J.
2019;30(7):1127-39;
(3) Arruda GT, Andrade DF, Virtuoso JF. Internal structure and classification of pelvic floor
dysfunction distress by PFDI-20 total score. J Patient Rep Outcomes. 2022;16;6(1):51.
- Please write as if you were going to explain to a clinician what the results of factor structure,
ceiling and floor effects, internal consistency and reliability mean. What is the importance of
this study for clinical practice?
- Other limitations: measurement errors, hypothesis testing for construct validity (comparison
with another instrument or between groups) and cross-cultural validity were not evaluated. Local
sample can also be a limitation and not be extrapolated to the whole country.