The same approach will be used for the assessment of the continuous secondary end-points where there are continual variables.
One-way ANOVA is used for continual variables, while a chi square test is used for categorical variables.
The CTs assisted in both selecting variables of greater importance in the problem of classification and determining the best cut-off points for the continual variables.
The mean was calculated for all continual variables and the frequency for discrete variables, stratifying by sex, age group and deprivation index.
We used DXA determined osteoporosis (BMD ≤ -2.5) as the dependent variable, and RA T-score and QUS BUA as independent continual variables.
Baseline characteristics and abnormal rates were compared between subgroups with/without MetS outcome within five years using the t-test and the χ2 test for categorical and continual variables as appropriate.
We evaluated the difference between the cases and controls in the distribution of categorical variables (sex, Hp antibody positivity, smoking and drinking status) and continual variables (age, pack-years and telomerase activity) using the Pearson χ2 test and the Student t-test, respectively.
If marginal distributions of continual random variable (X, Y) are F x) and G y), the relationships between Copula function C u, v) and Kendall rank correlation coefficient τ, Spearman rank correlation coefficient ρ, tail dependence λ are as follows, respectively.
We did not use continuous variables to represent income, education and occupations and perform latent profile analysis because (1) the continual measure of income and education has lower validity and efficiency compared to categorical income variable and (2) these two methods lead to quite similar results.
where p x, y) is the joint probability density function of continual random variables, and p(x) and p y) are the marginal probability density functions.
