Not a marker of association (AIPG 2011)
Ref: Park ; 22nd ed. 793, High Yield Statistics; Pg: 32, 36 & 47
P value, OR & correlation Coefficient are all markers of association except the value of alpha which is a test criterion or level for deciding whether to accept or reject a null hypothesis, also known as type I error.
According to convention, if P is less than or equal to .05, it is regarded as statistically significant. The smaller the P value, the greater the statistical significance or probability that the association is not due to chance alone. However, the statistical association (p value) does not imply causation.
Odds Ratio is a measure of the strength of association between the risk factor and outcome.
A correlation coefficient simply expresses the strength and direction of association or relationship between two quantitative variables, signified by ‘r’. Values of r varies from -1 to +1; the strength of the relationship is indicated by the size of the coefficient, whereas its direction is indicated by the sign.
The probability level at which it is decided that the null hypothesis is incorrect constitutes a criterion or significance level known as alpha.