Data, variables and measurement scales
Keywords:
Data, variables, measurement scalesAbstract
Biostatistics is part and parcel of biomedical research. The data from biomedical studiesrequire statistical treatment for its effective presentation and correct interpretation. Thechoice of appropriate statistical methods to be applied depends upon the kind of data andvariables. Different types of variables (characteristics) generate different types of data.Variables can be classified in many ways; qualitative and quantitative, nominal and ordinal ordiscrete and continuous. Different measurement scales are used to measure different types ofvariables; nominal & ordinal scales for qualitative and interval & ratio scale for quantitativevariables. Different statistical methods/tests are employed for presentation and analysis ofdifferent types of data. For qualitative data; percentage, proportions, rate, ratios, standarderror of proportions, chi-square test etc. are applied. While mean, range, standard deviation,coefficient of variation, correlation coefficient, etc. are employed in case of quantitative data.This article, second of the series, describes various types of data, variables and measurementscales.Learning objective At the completion of this article, the reader should have a clearunderstanding of different types of data, variables and their measurement scales, and be ableto utilize these concepts in organizing the research of his own and for interpreting the resultsof other studies.References
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