Analysis of Two Independent Samples with Non Normality Using Non Parametric Method, Data Transformation and Bootstrapping Method

作者：Guan Ng Chong^*; Yusoff Muhamad Saiful Bahri; Zainal Nor Zuraida; Yun Low Wah

来源：International Medical Journal, 2012, 19(3): 218-220.

• non parametric
• transformation
• bootstrapping
• non normality

Objective: To compare the use of non parametric test, data transformation and bootstrapping method in the analysis of two independent samples with non normal distribution. %26lt;br%26gt;Method: 202 patients who were discharged from the psychiatric ward, University Malaya Medical Centre (UMMC) from 27th August, 2007 to 15th April, 2008 were recruited. The general psychopathology was measured with brief psychiatric rating scale (BPRS-24). On follow up, the patients who had early readmission (%26lt; 6 months) were identified. The BPRS score between the patients with and without early readmission were compared using the Mann-Whitney test, logarithm data transformation and bootstrapping method. %26lt;br%26gt;Result: All three methods rejected the null hypothesis (p %26lt; 0.05). The effect estimation of the means difference is shown in bootstrapping method (95% confidence interval: 6.62-6.98). %26lt;br%26gt;Conclusion: Non parametric method, logarithm data transformation and bootstrapping method can be used for hypothesis testing in the analysis of two independent samples with non normality. Effect estimation is only provided by bootstrapping method.

• 出版日期2012-9