Reviewer's report
Title:Independent external validation of cardiovascular disease mortality in
women utilising Framingham and SCORE risk models: a mortality follow-up study
Version:1Date:31 July 2014
Reviewer: Ivanny Marchant
Reviewer's report:
Summary
In the article “Independent external validation of cardiovascular disease mortality
in women utilising Framingham and SCORE risk models: a mortality follow-up
study” by Goh et al., the authors report the findings of an external validation
study designed to evaluate the applicability of three different risk estimation
systems: Framingham, SCORE for low risk regions and SCORE for high risk
regions in a cohort of 4487 Australian adult women (age range 20 – 69 years) by
comparing the risks predicted and the risks observed over ten years of follow up.
The manuscript is well written and adheres to relevant standards. It contains,
however, some shortcomings that merit to be revised.
Major Compulsory Revisions
(which the author must respond to before a decision on publication can be
reached)
- Methods:
Why did the authors choose the Framingham and SCORE models? As the
authors have stated, there is a number of published risk predictors that could be
used in cardiovascular primary prevention. They should introduce why they
chose the Framingham and SCORE risk equations to evaluate their applicability
in the study population.
- Discussion
1. It appears difficult to know whether this paper represent a useful contribution
to the field given the shortage of arguments in the discussion. Focused on
calibration aspects, the present results are compared with the results obtained
from an important number of validation studies in many different populations. In
contrast with the big number of references, the discussion seems rather
superficial; with no explanations on the possible causes of calibration defaults; or
the eventual similarities/ differences between the cohort study population and the
populations they refer to.
2. Regarding discrimination thresholds, their implications on the size of treatment
target populations and expected benefit from treatment should be discussed as
well as its economic consequences.
3. The authors made the assumption that no one presented with left ventricular
hypertrophy in their cohort because the data was not available. Such an
assumption may have introduced some bias in the risk estimates leading to
underestimation of CVD risk by the Framingham risk predictor. Ideally, the
magnitude of this potential gap could have been estimated or at least be
considered as one of the limitations of the study. It is likely that the prediction by
Framingham will be improved by taking into account the presence of left
ventricular hypertrophy in Australian populations.
4. It would be desirable/useful to have a comparison between the performance
-and implications of use - of the two risk scores retained (Framingham and
SCORE-low). This would add value to the article since more interesting research
questions would be addressed.
- Conclusion
1. The authors indicate that Framingham and SCORE-low model are
recommended for use in the Australian population. Since the study population
consisted of Australian women aged 20 to 69 years, conclusions could only be
extended to the adult women Australian population.
Minor Essential Revisions
(such as missing labels on figures, or the wrong use of a term, which the author
can be trusted to correct)
Discretionary Revisions
(which are recommendations for improvement but which the author can choose
to ignore)
Figures:
- Error bars for the risk estimates should be included in order to judge for the
accuracy of the estimates within each category.
- Why did the authors use lines to join the predicted risks points? As these are
point estimates, there is no need to connect them.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare that I have no competing interests