Indian Journal of Ophthalmology

: 2008  |  Volume : 56  |  Issue : 4  |  Page : 341-

Authors' reply

Rajul Parikh, Annie Mathai, Shefali Parikh, G Chandra Sekhar, Ravi Thomas 
 L.V. Prasad Eye Institute, Banjara Hills, Hyderabad, Andhra Pradesh, India

Correspondence Address:
Rajul Parikh
L.V. Prasad Eye Institute, L. V. Prasad Marg, Banjara Hills, Hyderabad - 500 034, Andhra Pradesh

How to cite this article:
Parikh R, Mathai A, Parikh S, Sekhar G C, Thomas R. Authors' reply.Indian J Ophthalmol 2008;56:341-341

How to cite this URL:
Parikh R, Mathai A, Parikh S, Sekhar G C, Thomas R. Authors' reply. Indian J Ophthalmol [serial online] 2008 [cited 2020 Apr 2 ];56:341-341
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Full Text

Dear Editor,

We are grateful for the comments by Skaik YA and before we try to explain ourselves, [1] happily agree with all of them. We hasten to clarify why we omitted most of what we did, but first out, are grateful for only partial disagreement - which implies that there is a lot of agreement too. To explicate: we wrote this article [2] from a clinical perspective and intended it for the "practice section" of the journal, not for research methodology, monitoring and other uses that tests may be put to. We had no idea it would land up in the research methodology section and evoke such legitimate concerns; although out of our control, we do apologize.

Having stated the purpose of the piece clearly in the abstract itself we went on to elaborate on our objective: basic knowledge for the clinical ophthalmologist to apply in day-to-day practice. The reason being that most clinicians that we have interacted with seem to feel that these important concepts belong to medical school public health, microbiology and perhaps research; we intended to demonstrate that these important principles are essential in everyday clinical practice. Essentially, this is part of a series of articles we have written for the journal over a period of time in order to popularize and spread the "word" of clinical epidemiology. [3],[4],[5]

We confess that we were ignorant of the origins of the terms and the seminal reference and thank the writer for this information. There are many books on the subjects and several ways of looking at concepts such as true positives and true negatives. We clearly defined what we meant by these terms when we used them in the text and feel that explicit definitions help reduce disagreement, at least to partial disagreement. We end on that note by quoting Medawar from the preface of our clinical bible: "The innocent belief that words have an essential or inward meaning can lead to appalling confusion and waste of time. It seems to us that the "essentialist" (which invokes ontology and insists that every word has a single, formally correct definition) is simply not up to the task that must be carried out in clinical and health care." [6]


1Skaik YA. Understanding and using sensitivity, specificity and predictive values. Indian J Ophthalmol 2008;56:341.
2Parikh R, Mathai A, Parikh S, Chandra Sekhar G, Thomas R. Understanding and using sensitivity, specificity and predictive values. Indian J Ophthalmol 2008;56:45-50
3Korah S, Thomas R, Muliyil J. An introduction to clinical decision analysis in ophthalmology. Indian J Ophthalmol 1999;47:41-8
4Thomas R, Braganza A, Oommen LM, Muliyil J. Confidence with confidence intervals. Indian J Ophthalmol 1997;45:119-23.
5Thomas R, Padma P, Braganza A, Muliyil J. Assessment of clinical significance: The number needed to treat. Indian J Ophthalmol 1996;44:113-5.
6Sackett DL, Haynes RB, Guyatt GH, Tugwell P. Clinical epidemiology: A basic science for clinical medicine. 2 nd ed. New York: Little, Brown and Co; 1991.