The hidden side of clinical trials

Watch the AllTrials TEDx talk on YouTube

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Evidence matters to the public

Join us on 1st November at Parliament to make the case

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Plant Science Panel

Insecticides, biofuels, GMOs …

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'The Ugly Truth'

by Tracey Brown, director of Sense About Science

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How close a measurement of something is to its true value.


Statements offered in support of your conclusion or opinion.


The answer you can give to a question – based on data (or evidence) and argument.


A sample that has not been given the treatment you are testing, or has not been exposed to the factor your are investigating.  You can compare the control to a sample that has been given the treatment.

copy editor

Someone who checks the punctuation, grammar and style of a paper before publication.


Pieces of information about a process or object. Good data are both valid and reliable.


Rules about how to behave, based on what is right and what is wrong.  The ethics of testing on animals, for example, is often discussed in the public


Data used to support an argument, conclusion, or explanation.


A practical procedure, carried out to collect data to test a hypothesis.


A series of linked statements, or story, that accounts for something happening. An explanation can only be called ‘scientific’ if it is accepted by a group of other scientists.


A testable statement suggesting how something happens. A hypothesis is usually based on observations.


A publication that publishes the latest scientific findings.


Something you can say about the world, based on information from your senses.


All scientific research builds on previous work, but research that advances the field of knowledge are said to be original. 


The effect(s) of a change.  e.g. If you start exercising, one outcome is that your body makes more sweat.


When a piece of scientific research is written up for publication, it is called a paper.


A scientist who works in the same field.

peer review

Scientists publish their data and explanations as articles in journals. Before they are published, other scientists read the articles. They evaluate the way the scientist has done their work, the quality of their data, and how good their explanation is. This is peer review. If other scientists think the work is good, then it is more likely to be published.


When repeated measurements of the same thing are close to each other, the data is reliable. You can have more confidence in conclusions and explanations if they are based on reliable data.


Scientists use many samples to ensure accuracy.  Each sample in a group is treated the same way, so they are called 'repeats'.


Repeating something, e.g. taking two or three measurements of the same value in an experiment.


A group taken from a population.

sample size

How many there are in a sample.

scientific community

A group of scientists who work in the same field. They may share ideas, and discuss each others’ work. Also describes as 'peers'.


In the peer review process, 'significance' describes the importance of a piece of research.  Statistical significance describes a result that is not down to chance.


A study is only valid if it the appropriate controls and measurements have been used.