Letter to Editor:
Regarding the article by Krishnamurthy et al. on 60 laryngectomized patients with prosthetic voice rehabilitation (Mar. 9 issue) [1], 82% of patients preserve successful trachea-esophageal speech. These data agree with the existing literature [2]. What’s striking about the obtained results is the excellent mean device life-time (16 months), which is much higher than the one shown in the literature in general [3], as well as in the most recent articles [4, 5] that place the cipher in 2–4 months. This is a fact that the authors themselves highlight in their own review. Perhaps this is due to the extreme values shown (1–42 months), and it may be more convenient to show the median. In any case, the fact of not explaining the statistical methodology does not allow us to check if these results are adequate.
To confirm how these results were obtained, it would be convenient to know what type of statistical analysis was carried out. The existence of a follow-up with a wide range (1–50 months) could cause an important bias if the different times were not weighted. An explanation of how the devices’ survival was valued, perhaps by Cox regression or by Kaplan Meyer curves, is necessary. Likewise, the ordinary regression models do not take into account the time, so a special type of analysis such as a binomial or a Poisson model should have been used with the objective of controlling the effect of follow-up time. Another aspect to take into account is the motive of replacement, which is an aspect not included in this work.
Compliance with Ethical Standards
The author declares that he has no conflict of interest.
References
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