Categorical variables are also known as qualitative (or discrete) variables. These categorical variables can be further classified as being nominal, dichotomous or ordinal variables. Each of these types of categorical variable (i.e., nominal, dichotomous and ordinal) has what are known as categories or levels. These categories or levels are the descriptions that you give a variable that help to explain how variables should be measured, manipulated and/or controlled.
BetimolÂ® (timolol ophthalmic solution), 0.25% and 0.5%, is a non-selective beta-adrenergic antagonist for ophthalmic use. The chemical name of the active ingredient is (S)-1-[(1,1-dimethylethyl)amino]-3-[(4-(4-morpholinyl)-1,2,5-thiadiazol-3-yl]oxy]-2-propanol. Timolol hemihydrate is the levo isomer.
Arimidex is the brand name of the generic drug anastrazole, used to treat breast cancer in postmenopausal women. Arimidex belongs to class of drugs known as nonsteroidal aromatase inhibitors, which slow or stop the growth of breast cancers that are stimulated by estrogen by decreasing the amount of estrogen the body makes after menopause.