Mann-Whitney test

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Mann-Whitney test

[¦man ′wit·nē ‚test]
(statistics)
A procedure used in nonparametric statistics to determine whether the means of two populations are equal.
References in periodicals archive ?
After calculating the total number of half-entries, we used the Mann-Whitney U test to determine whether differences existed over time and between trap types.
Kruskal-Wallis and Mann-Whitney U tests were used to assess pattern of injury and type of teeth involved.
The Mann-Whitney U test was calculated for the scores of CBCL in withdrawn tendency aspect of children with unintentional poisoning and without poisoning.
Comparison of all the latest thresholds yielded a significant difference (p<0.05, Mann-Whitney U test) between the 12th hour group (20 dB nHL) and the other two groups (10 dB nHL in the 24th hour group and 10 dB nHL in the 28th day group) and between the 24th hour (10 dB nHL) and the 28th day (10 dB nHL) groups (Figure 1).
For the Mann-Whitney U test to be applied, the following assumptions were met: (a) a coincidence of the sample; and (b) independence of the observations.
Post-hoc Bonferroni-corrected Mann-Whitney U tests of baseline characteristics for the abortion subgroups revealed no significant differences between subgroups for mean age, gestational age, number of pregnancies, and number of previous abortions (p>0.05), although the number of births was significantly higher in the incomplete abortion group than in the complete abortion group (p<0.05).
Using a Cell Counting Kit-8 assay, viability of cells derived from the knee synovium was significantly higher than that of cells derived from the hip synovium (knee versus hip, 100% versus 88.4%, P < 0.01, Mann-Whitney U test) (Figure 4(b)).
fT3 and fT4 concentrations did not significantly differ between children who did or did not show catch-up growth (mean hormone concentration (SD); fT3: 6.9 (0.7) versus 6.7 (0.7)pmol/l, p = 0.277; fT4: 16.0 (2.1) versus 16.3 (1.5) pmol/l, p = 0.628; Mann-Whitney U Test with Bonferroni correction, adjusted significance level [alpha] = 0.007).
The Student t-test was used to compare the mean age while the Mann-Whitney U test was used to compare the medians of CD4 cells, interleukin-6, and interleukin-10.
Table 3 shows the test statistics for significance (p <.05) utilizing the Mann-Whitney U test.
Mann-Whitney U test is used to compare the difference between two independent groups when the dependent variable is either ordinal or continuous but not normally distributed.