Sample size and statistical analysis
According to the study by Lacroix et al.11, at least
63 elderly people in each group will be needed to meet a statistical
level of 80% in detecting a difference of 2 points adopting an alpha
error of 5%, considering a standard deviation of 4 points. The
principle of intention-to-treat analysis was considered, and the
sensitivity analysis was performed through simple imputation using the
mean of the variables. To test the data normality, the histogram, mean
and median, standard deviation, skewness and kurtosis were analyzed, and
the Shapiro-Wilk normality test was used for confirmation. Due to the
normal distribution of the variables, parametric statistics were used,
and the intragroup comparisons were made through the Student test for
paired samples. The analysis of subgroups of age groups, which was
pre-specified in the study protocol, as it was done with more than two
groups that presented parametric distribution, one-way ANOVA was used,
followed by the one-way ANOVA Tukey’s multiple comparison test. The
significance level established for all analyzes was p <0.05
and statistical procedures were analyzed and processed in the
Statistical Package of the Social Sciences - SPSS version 21.0 (IBM,
Armonk, NY, USA).