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. 2019 Jan-Mar;22(1):67-72.
doi: 10.4103/aca.ACA_157_18.

Descriptive statistics and normality tests for statistical data

Prabhaker Mishra  1 , Chandra M Pandey  1 , Uttam Singh  1 , Anshul Gupta  2 , Chinmoy Sahu  3 , Amit Keshri  4
Affiliations

Descriptive statistics and normality tests for statistical data

Prabhaker Mishra et al. Ann Card Anaesth. 2019 Jan-Mar.

Abstract

Descriptive statistics are an important part of biomedical research which is used to describe the basic features of the data in the study. They provide simple summaries about the sample and the measures. Measures of the central tendency and dispersion are used to describe the quantitative data. For the continuous data, test of the normality is an important step for deciding the measures of central tendency and statistical methods for data analysis. When our data follow normal distribution, parametric tests otherwise nonparametric methods are used to compare the groups. There are different methods used to test the normality of data, including numerical and visual methods, and each method has its own advantages and disadvantages. In the present study, we have discussed the summary measures and methods used to test the normality of the data.

Keywords: Biomedical research; descriptive statistics; numerical and visual methods; test of normality.

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Conflict of interest statement

None

Figures

Figure 1
Figure 1
Histogram showing the distribution of the mean arterial pressure
Figure 2
Figure 2
Normal Q–Q Plot showing correlation between observed and expected values of the mean arterial pressure
Figure 3
Figure 3
Normal P–P Plot showing correlation between observed and expected cumulative probability of the mean arterial pressure
Figure 4
Figure 4
Boxplot showing distribution of the mean arterial pressure
See this image and copyright information in PMC

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