Glossary


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Agenţia Naţională a Medicamentului şi a Dispozitivelor Medicale


Agentur für Gesundheit und Ernährungssicherheit


Agenzia Italiana del Farmaco


Agglomerate

Cluster of independent but similar things collected or formed into a mass.

Allocation concealment

A technique used to prevent selection bias by concealing the allocation sequence from those assigning participants to intervention groups, until the moment of assignment. Allocation concealment prevents researchers from (unconsciously or otherwise) influencing which participants are assigned to a given intervention group.

Taken from Consort http://www.consort-statement.org/resources/glossary

Allogeneic cells

Allogeneic cells are cells obtained from a donor, such as bone marrow or umbilical cord blood.

Alternative hypothesis

In medicines development one might for example formulate the hypothesis that a new treatment for a disease is better than the existing standard of care treatment. If the new treatment is called B™, and the standard of care treatment is called A™ then the hypothesis states that B™ is better than A™. This hypothesis would be referred to as the alternative hypothesis. It is also known as the research hypothesis™.

The concept of the alternative or research hypothesis is a central part of formal hypothesis testing.

One might presume that scientists would set about proving the alternative or research hypothesis (B is better than A), but that is not the case. Instead this objective is approached indirectly. Rather than trying to prove the alternative or research hypothesis, scientific method assumes that in fact B does not differ from A “ that the new treatment does not offer an improvement over the standard of care treatment. This is known as the null hypothesis.

In order to understand why scientific method adopts this indirect approach in hypothesis testing it may be useful to bear in mind what Albert Einstein said: No amount of experimentation can ever prove me right a single experiment can prove me wrong.™

So, scientists use statistical tests to determine if the null hypothesis is true or false. If they can show with a certain likelihood (probability) that the null hypothesis is false, then the alternative or research hypothesis would be adopted (must be true)

Ames test

The Ames test is a biological assay that uses bacteria to analyse whether a chemical can cause mutations in the DNA. A positive test indicates that the chemical is mutagenic and therefore may act as a carcinogen.

Amorphous

Having no definite or specific shape or form. Shapeless.

Amt für Gesundheit



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