I've selected the Parent/Teacher disruptive behavior disorder (DBD) rating scale which is based on the Diagnostic and Statistical Manual of Mental Disorders as one of the assessments I would utilize in a behavior analysis setting

I've selected the Parent/Teacher disruptive behavior disorder (DBD) rating scale which is based on the Diagnostic and Statistical Manual of Mental Disorders as one of the assessments I would utilize in a behavior analysis setting. Additionally, I would also utilize the Affective Reactivity Index: The ARI scales. What are the statistical concepts, including scales of measurement, measures of central tendency, indices of variability, shapes and types of distributions,and correlations for these two assessments?