Understanding Nutrition Information
Glossary
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alternative hypotheses or hypothesis - Another possible explanation for the results.

bias - Someone or something in a study that ignores a confounding variable. This introduces error into the results of a study.

blind study or double blind - A scientific study in which the subjects do not know whether they are receiving an experimental treatment or a placebo. In a double blind study, neither the researchers nor the subjects are aware of which treatment is received until after the study is completed.

case studies - Accounts of a doctor's observations and laboratory results of individual patients, which may lead to new areas of scientific study. Case studies do not seek to control confounding variables, do not take into account the variable nature of a disease, do not establish a method with control and experimental groups, and do not exhibit other characteristics of a scientific study.

clinical trial - A double blind controlled study that is characterized by its use of a large sampling of human subjects. Clinical trials are generally expensive and time-consuming due to their efforts to control confounding variables, to test alternative hypotheses, to replicate the study, and to offer evidence for the effectiveness of a claim.

confounding variable or confusing factor - A factor or variable in the subjects being studied that introduces error or skews the results of the study.

control group - In a scientific study, the group of subjects that serves as the standard to which the experimental group is compared to determine the effectiveness of a treatment. In a blind study, the control group is identical to the experimental group, except the control group would receive a placebo in place of the treatment or product being tested.

controlled observation - A scientific study that includes a large sampling of subjects, is screened for confounding variables, and is divided into control and experimental groups.

experimental group - The group of subjects in a scientific study that receives a treatment or tests the hypothesis.

peer review - A critical analysis of the scientific study by other scientists, drawing on the expertise and critical review of other professionals in the same field of study.

placebo - A procedure or product with no therapeutic value. Commonly referred to as a "sugar pill." In blind studies, it is made to look exactly like the product being tested and is given to the control group so that circumstances of the study can be controlled and evaluated for effectiveness.

reliability - Something that can be reproduced, and each time will give the same results.

replicate - To repeat.

sampling or random sampling - Sampling is the method of choosing a certain number of people from the population you want to study. Random sampling means that each person in the population has an equal chance of being selected for the study.

S.E.A.R.C.H. formula - An acronym that represents four steps of analysis and effectively applies the principles of scientific thinking. It is credited to the authors Theodore Schick, Jr. and Lewis Vaughn in their book, How To Think About Weird Things.

side effects - An adverse effect or consequence, that is not expected or does not produce the desired result of a treatment.

social or cultural practices - Characteristics of a group of subjects.

validity - Accuracy or truthfulness in regard to a study's conclusion.

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