AbstractVariation is a law of nature that makes this universe beautiful. In healthcare, two human beings, though genetically similar, may not respond equally to the same drug. The same drug may also have a varying response and become ineffective in an individual over a period of time. When we look at a population of individuals, variations are so prominent that no two individuals are ever exactly alike. There may be several factors for these variations among individuals which include those

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... are due to biological, genetic, environmental, or ecological effects [1]. Variations also occur when we sample these individuals. Moreover, variability in the observers themselves may also contribute to variations in assessment. These variations are bound to occur whatever may be the reasons and consequently lead to uncertainties in clinical practice, identification of risk factors, and policy planning.