Non-Parametric Test for Ordered Medians: The Jonckheere Terpstra Test

Authors

  • Arif Ali Department of Research, Dow University of Health Sciences, Karachi, Pakistan
  • Abdur Rasheed Department of Research, Dow University of Health Sciences, Karachi, Pakistan
  • Afaq Ahmed Siddiqui Department of Pharmacy, University of Karachi, Karachi, Pakistan
  • Maliha Naseer Department of Community Health Sciences, Aga University, Karachi, Pakistan
  • Saba Wasim Department of Community Health Sciences, Aga University, Karachi, Pakistan
  • Waseem Akhtar Department of Radiology, Aga Khan University, Karachi, Pakistan

DOI:

https://doi.org/10.6000/1929-6029.2015.04.02.6

Keywords:

Jonckheere Terpstra test, non parametric test, comparison of medians.

Abstract

In clinical trials, sample size is usually lesser as compared to other epidemiological studies to make it more feasible and cost effective. Small sizes of such trials discourage the use of parametric test due to violation of the assumption under which they are applicable. Therefore, the use of nonparametric test is substantial in clinical trials to test two or more independent samples. The Kruskal-Wallis h test is an alternative to one-way ANOVA and can be used to identify significant differences among different populations. When we have several independent samples and assumed to be arranged orderly, Jonckheere Terpstra test is a best choice to compare population medians instead of means. For the application of Jonckheere Terpstra test the data from the study of cleaning methods for ultrasound probes are used. The Jonckheere Terpstra test is recommended over Kruskal-Wallis h test as it compares and provides significant difference between more than two population medians when they arranged in order. Therefore, the aim of this research paper was to explore the use and significance of Jonckheere-Terpstra test with the use of practical example.

Author Biographies

Arif Ali, Department of Research, Dow University of Health Sciences, Karachi, Pakistan

Research

Abdur Rasheed, Department of Research, Dow University of Health Sciences, Karachi, Pakistan

Research

Afaq Ahmed Siddiqui, Department of Pharmacy, University of Karachi, Karachi, Pakistan

Pharmacy

Maliha Naseer, Department of Community Health Sciences, Aga University, Karachi, Pakistan

Community Health Sciences

Saba Wasim, Department of Community Health Sciences, Aga University, Karachi, Pakistan

Health Sciences

Waseem Akhtar, Department of Radiology, Aga Khan University, Karachi, Pakistan

Radiology

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Published

2015-05-21

How to Cite

Ali, A., Rasheed, A., Siddiqui, A. A., Naseer, M., Wasim, S., & Akhtar, W. (2015). Non-Parametric Test for Ordered Medians: The Jonckheere Terpstra Test. International Journal of Statistics in Medical Research, 4(2), 203–207. https://doi.org/10.6000/1929-6029.2015.04.02.6

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Section

General Articles