Statistical Analysis: Data Presentation and Statistical Tests

  • Mahalakshmy Thulasingam
  • Kariyarath Cheriyath Premarajan


  • Data analysis should be planned in line with objectives of the study. Quality assured data entry, data cleaning and construction of dummy tables are essential steps before data analysis.

  • Descriptive statistics summarize the data obtained from the study subjects. The measures could be rate, proportion, odds ratio, relative risk, mean, median, mean difference, etc.

  • Inferential statistics make inference about the population using the data from the study sample. In inferential statistics, 95% confidence interval and p-value are calculated.

  • In comparison with p-value, 95% confidence interval gives information on the magnitude of effect in addition to statistical significance. Clinical significance is important than statistical significance.

  • Choice of statistical test of significance depends on the type of data (numerical, categorical) and its distribution (normal or non-normal).



The authors thank Dr Tanveer Rehman, Junior Resident and Dr Gunjan Kumar, Senior Resident, Department of PSM for critically reviewing the manuscript


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Mahalakshmy Thulasingam
    • 1
  • Kariyarath Cheriyath Premarajan
    • 1
  1. 1.Department of Preventive and Social MedicineJawaharlal Institute of Postgraduate Medical Education and ResearchPondicherryIndia

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