Title: Predictive Model for Identification of Gangrenous or Perforated Appendicitis in Adults:
A Multicenter Retrospective Study
Version: 7 Date: 26 Aug 2024
Reviewer's report:
The authors developed model for predicting complicated appendicitis, which showed acceptable
performance in the external validation set, as well as in the development dataset.
It would be ideal to compare the model's performance with radiologists' assessments made
without the use of clinical variables. Or, it would be ideal if it could compared with previous
models such as that by Avansov's or Kim's (https://pubmed.ncbi.nlm.nih.gov/32914350/).
Could CT reports be retrospectively analyzed to evaluate how well radiologists differentiate
between complicated and uncomplicated appendicitis? Or at least add in discussion, the reported
performance in the literature.
One limitation of this model is the inclusion of D-dimer, which is not always routinely measured
in the emergency department.
For this model to have clinical utility, it must serve a specific purpose—in this
case, sensitively identifying patients with complicated appendicitis so they can receive
appendectomy rather than conservative treatment. For example,  a previous study (https://
pubmed.ncbi.nlm.nih.gov/32914350/) has shown a model with high sensitivity of over 90%.
In discussion "External validation using patient data from the Fifth Affiliated Hospital of Sun
Yat-sen University showed no significant variations in baseline characteristics between the
training and testing sets, confirming their suitability as training and validation sets. " why should
there be no significant variations between the training and the testing sets? what's the point of
external validation if the patient characteristics are the same between the two datasets? The point
of external validation is to test the model in another patient sample and see if the results from
the development dataset can be generalized to other patient samples.
Title: Predictive Model for Identification of Gangrenous or Perforated Appendicitis in Adults:
A Multicenter Retrospective Study
Version: 7 Date: 26 Aug 2024
Reviewer's report:
The authors developed model for predicting complicated appendicitis, which showed acceptable
performance in the external validation set, as well as in the development dataset.
It would be ideal to compare the model's performance with radiologists' assessments made
without the use of clinical variables. Or, it would be ideal if it could compared with previous
models such as that by Avansov's or Kim's (https://pubmed.ncbi.nlm.nih.gov/32914350/).
Could CT reports be retrospectively analyzed to evaluate how well radiologists differentiate
between complicated and uncomplicated appendicitis? Or at least add in discussion, the reported
performance in the literature.
One limitation of this model is the inclusion of D-dimer, which is not always routinely measured
in the emergency department.
For this model to have clinical utility, it must serve a specific purpose—in this
case, sensitively identifying patients with complicated appendicitis so they can receive
appendectomy rather than conservative treatment. For example,  a previous study (https://
pubmed.ncbi.nlm.nih.gov/32914350/) has shown a model with high sensitivity of over 90%.
In discussion "External validation using patient data from the Fifth Affiliated Hospital of Sun
Yat-sen University showed no significant variations in baseline characteristics between the
training and testing sets, confirming their suitability as training and validation sets. " why should
there be no significant variations between the training and the testing sets? what's the point of
external validation if the patient characteristics are the same between the two datasets? The point
of external validation is to test the model in another patient sample and see if the results from
the development dataset can be generalized to other patient samples.
Please review this paper.
user
Title: Predictive Model for Identification of Gangrenous or Perforated Appendicitis in Adults:
A Multicenter Retrospective Study
Version: 7 Date: 26 Aug 2024
Reviewer's report:
The authors developed model for predicting complicated appendicitis, which showed acceptable
performance in the external validation set, as well as in the development dataset.
It would be ideal to compare the model's performance with radiologists' assessments made
without the use of clinical variables. Or, it would be ideal if it could compared with previous
models such as that by Avansov's or Kim's (https://pubmed.ncbi.nlm.nih.gov/32914350/).
Could CT reports be retrospectively analyzed to evaluate how well radiologists differentiate
between complicated and uncomplicated appendicitis? Or at least add in discussion, the reported
performance in the literature.
One limitation of this model is the inclusion of D-dimer, which is not always routinely measured
in the emergency department.
For this model to have clinical utility, it must serve a specific purpose—in this
case, sensitively identifying patients with complicated appendicitis so they can receive
appendectomy rather than conservative treatment. For example,  a previous study (https://
pubmed.ncbi.nlm.nih.gov/32914350/) has shown a model with high sensitivity of over 90%.
In discussion "External validation using patient data from the Fifth Affiliated Hospital of Sun
Yat-sen University showed no significant variations in baseline characteristics between the
training and testing sets, confirming their suitability as training and validation sets. " why should
there be no significant variations between the training and the testing sets? what's the point of
external validation if the patient characteristics are the same between the two datasets? The point
of external validation is to test the model in another patient sample and see if the results from
the development dataset can be generalized to other patient samples.
assistant