Keywords
Correlación de datos
Medicina Clínica
Investigación Statistics, Nonparametric
Correlation of Data
Clinical Medicine
Research
How to Cite
Abstract
Correlation is a statistical measure that allows knowing the degree of linear association between two quantitative or ordinal variables (x, y). It also determines the strength of the association and the direction that this relationship takes by calculating the correlation coefficient, the result of which can vary in the interval [-1, +1]. The closer the correlation coefficient is to 1, the stronger the association. When a relationship is random or does not exist, the coefficient tends to be zero. Correlation coefficients only measure linear relationships of continuous variables with normal (Pearson) or monotone distribution with ordinal variables organized in ranks or hierarchies (Spearman), which tend to change at the same time, but not necessarily at a constant rate. Correlation tests are widely used in biomedical research to determine the tendency of two variables to go together, which is also called covariance; This does not necessarily mean that when a correlation (+/-) is reported, it represents a cause and effect relationship.
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