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.
Tramadol (as the racemic, cis-hydrochloride salt), is available as a generic in the U.S. from any number of different manufacturers, including Amneal, Caraco, Mylan, Cor Pharma, Mallinckrodt, Pur-Pak, APO, Teva, and many more. Typically, the generic tablets are sold in 50 mg tablets.