Statistical analysis
Categorical variables were expressed as numbers and percentages, whereas
continuous variables were summarized as mean and standard deviation.
Chi-square test was used to compare categorical variables between the
groups. The normality of distribution for continuous variables was
confirmed with the Shapiro Wilk test. For comparison of continuous
variables between groups, the Student’s t-test or Mann-Whitney U test
was used depending on whether the statistical hypotheses were fulfilled
or not. To evaluate the correlations between measurements, Pearson
Correlation Coefficient or Spearman Rank Correlation Coefficient was
used depending on whether the statistical hypotheses were fulfilled or
not. All analyses were performed using IBM SPSS Statistics Version 20.0
statistical software package. The statistical level of significance for
all tests was considered to be 0.05.
SPSS referansı : IBM Corp. Released 2011. IBM SPSS Statistics for
Windows, Version 20.0. Armonk, NY: IBM Corp.