A regression with two or more predictor variables is called a multiple. regression. (When we need to note the difference, a regression on a single predic-. tor is called a simple regression.) Weâd never try to find a regression by hand, and. even calculators arenât really up to the task.
Different jurisdictions have different definitions of what constitutes a prescription drug. Rx is often used as a short form for prescription drug in North America-a contraction of the Latin word  recipe  (an imperative form of recipere) meaning take.
Answer: Yes, Limbrel does require a prescription. It is sold only as an Rx product, and the FDA regulatory product class of medical foods requires that it be used under the supervision of a physician. It is distributed through retail pharmacies behind the pharmacy counters. Return to Top â.