We would like to thank the readers for showing interest in our article. It is true that digital images of fingers to assess clubbing by measuring hyponychial angle can be analyzed directly by the use of appropriate softwares. The two softwares we have come across, which are useful for this purpose, are the Quartz PCI Scientific Image Management System, as used by Husarik and co- workers and CAD (Computer-Aided Design). Of these two software, Quartz PCI system was not available to us and we found CAD difficult to handle in the absence of specialized training. We are not aware of other better or easier ones for measuring such small angles.
On the other hand, the shadowgram technique, although a little more complicated compared to taking a digital photograph from a mobile phone camera, requires basic computer skills and measurement with a standard protractor. It is not costly and easy to set up in any typical clinic setting. Most physicians and technicians, we believe, would be able to easily adopt this technique without specialized knowledge of complicated software. Hence, we used the same in our work. Of course, the use of statistical software to directly measure the angles on digital photographs would be a much easier way provided availability of the required software as well as training is ensured.
It has been correctly pointed out that references to Table 1 have been omitted. We are sorry for the inadvertent omissions.
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