Spss 21.0 statistical analysis software package

Statistical analyses were conducted with the SPSS 21.0 statistical analysis software package (SPSS Inc. Chicago, IL). Univariate logistic analysis was first performed, based on which variables with p < 0.10 were selected for multivariate logistic analysis with a backward unconditional method. All tests were two-tailed and a p value < 0.05 was considered statistically significant.

Descriptive statistics were calculated for all the variables and expressed as the mean and standard deviation (SD). Normality was analyzed with the Shapiro–Wilk test. To check for differences between values of the same variable in the different positions, Student’s t-test or the Wilcoxon test were used, depending on the normality of the data. Percentage increases for all the stabilometric variables were calculated between the central position (0,0) and the positions (0,3) and (3,0).
The Pearson or Spearman correlation coefficient was calculated to determine the force and direction between the variable measurements.
The intraclass correlation coefficient (ICC) with a two-way mixed model and absolute agreement type at 95% confidence interval (CI) was calculated to determine the absolute reliability [35 (link)]. The ICCs were interpreted according to Portney and Watkins [36 ] and included 0.00 between 0.25: little to no relationship, 0.25 between 0.50: fair degree of relationship, 0.50 between 0.75: moderate to good relationship, and 0.75 between 0.9: good, and values greater than 0.90 indicate excellent reliability. All the statistical tests were performed with a significance level of α = 0.05. The SPSS 21.0 statistical analysis software package was used.

Statistical analyses were performed with the SPSS 21.0 statistical analysis software package (SPSS Inc. Chicago, IL). Demographic characteristics associated with HIV-1 genotypes were first analysed with univariate logistic regression. For each HIV-1 genotype, variables marginally significant with p < 0.10 in univariate logistic analysis were further analysed with multivariate logistic regression. The trend chi-square test was performed with the linear-by-linear association method under the chi-square test of SPSS. All tests were two-tailed and statistical significance was considered when p- value < 0.05.