There is still so far to go… Excellent overview on how often effect sizes and confidence intervals are reported (or not) in supposed high-impact factors (IF) journals – this shows again how IF sucks 🙂
“Nick Broad was an English football nutritionist and sport scientist who worked for some of the biggest football clubs including Blackburn Rovers, Birmingham City, Chelsea Football Club and Paris St-Germain. Broad was a close friend of former Chelsea manager, Carlo Ancelotti. He graduated from Aberdeen University. Aged 38, he died on 19 January, 2013 of an accidental traffic collision” (Wikipedia). Nick was an example for a lot of sport scientists working in high performance, including myself. Among many others, I will miss our discussions on the monitoring process.The section 3 of this paper is dedicated to him.
[first time I have an Editor discussing the relevance of a paper using general press/media or blog contents – this is very convincing, right?]
“The authors’ statement that HR cannot be used for fatigue monitoring and tracking is not correct. [I never said that btw, rather the converse, but my point was that it depends on how you measure HRV] In contrast, HR has long been used in practice to measure and evaluate fatigue, which has been well supported by both research and practice. As an example, I have enclosed a few links on HR and fatigue:
http://www.usacycling.org/follow-your-heart-using-heart-rate-to-gauge-fatigue.htm
http://www.transitionzone.com.au/content/physiology/Monitoring%20fatigue%20with%20HRV.pdf
Frontiers in Physiology (06/02/2014) – paper finally accepted in Frontiers, but what a fight !
Following one of our publications last year, the data from this recent study are perfect to show how much standardization is important. In the below example, the symbols represent the % differences in several variables between 2 groups of soccer players (more vs. less mature). The numbers above each symbol refer to the standardized differences (effect size), and the stars, to the chances for the differences to be substantial (i.e., clearly greater than the practically important effect, the smallest worthwhile change). Read more here about these key concepts.
What stands out is the lack of association between the % differences and their actual magnitude (i.e., standardized difference). This is particularly evident when comparing the differences in high speed activities (HSA, >45%, stdz diff +0.7) and height (5%, but stdz diff +1.6). In accordance with the standardized differences (and not the %), the chances for the differences in height are greater than for HSA ! Conclusion: don’t trust percentages. Report magnitudes and chances for the differences to be real.
This is probably one of the best applied set of examples to highlight how P values are hopless. A must read!
[posted by Matt Weston, paper just rejected from MSSE]
General. Reviewer 1 – you need to write more in the active voice. Reviewer 2 – write in the third person.
Statistical review. Our study was a clustered before and after controlled study. ANCOVA was used with the change as the dependent variable and baseline scores as the covariate. Furthermore, individual responses were quantified as a SD. Selection of reviewer comments: Why log transform if the data are normally distributed? Evaluate the effects on the difference between groups. What is the relevance of adjusted values? Why report individual responses to an intervention. I expected more of a review from this journal.
[agree, Matt. You cannot completely blame the bad reviewers, they probably did their best^^. But for such a journal, it is the editor that allowed this review to be sent to you who is to blame…]
[a nice comment reported by Grant Abt]
“I agree with the effect size statistics used in the manuscript, but I suggest additionally presenting traditional p-values. They are easier to understand and might improve citation of the manuscript.”
[ah, yes, because of course, the more important is to get your manuscript cited….the practical aspects for practitioners, which are definitely better reflected with magnitude-based statistics, don’t matter! ]
European J of Sport Science – 24/10/13
Another rejection from the Scandinavian Journal of Medicine and Science in Sports in my Inbox. I am not worried about the rejection itself, but once more time, about the very poor comments from the Editor, Stephen Harridge. Paper not even sent for review.
Here are the comments from the Section Editor [with my responses in Italics]
In this study the authors claim that training loads at certain intensities modified resting heart rate variability (HRV).
There are several studies on this issue: [Actually, there is NO study in elite athletes, and NO study on proper training load over a training program (not just a single exercise)]
and so far it seems that HRV assessment with 5-6 min recordings is rather imprecise and highly variable. A more extended recording (overnight for example) will represent much better HRV [1) this possible greater variability has still to be shown, and 2) considering the sleep stage-dependency of HRV and the direct effect on HRV of both sleep quality and physical activity the day before, I believe that standardized resting (morning) measures – less affected by prior activity the day before – will be less variables. In short, even he could be right, the editor statement is NOT based on scientific evidences.]
Unfortunately, no effort has been made to determine with other methods if parasympathetic/sympathetic balance was really modified. [Do you have many alternative methods to use on elite athletes (Olympic champions)?]
There was no control group: [fine but: 1) we used is a within-subjects modelling approach, so controls are not required. 2) how do you built a control group to compare against Elite athletes?]
The discussion is too speculative and the conclusions as well.” [NO comments]
At the bottom of the letter, you can read:
“Thank you for considering the Scandinavian Journal of Medicine and Science in Sports for the publication of your research. I hope the outcome of this specific submission will not discourage you from submitting other papers to the journal in the future.
Yours sincerely, Stephen Harridge, Editor-in-Chief. Scandinavian Journal of Medicine and Science in Sports”
[Stephen, we have a problem. And this is not new (see previous stories, where positive reviewers’ comments were disregarded and where we were criticized for not blinding a cold bath). Stephen, you can now be sure that you managed to discourage us from submitting other papers to the journal in the future.]
Martin
[Nothing much to add, this is brilliant]
Any comments? 