Glossary of Research Terms

Adverse events

An adverse even is any type of unexpected ill health a patient experiences while taking part in a research study. These are usually everyday problems such as headaches or maybe a rash. Very occasionally someone suffers a more serious episodes of ill health while taking part in a research study which may involve hospital admission. An adverse event is not necessarily caused by the treatment involved in the research study. It is quite possible that the same health problem would have happened anyway even if the person wasn't taking part in the research. However, researchers do need to know about all health problems so they can decide whether it may be linked to a study treatment or medication. They will make a record of the problem and if it is serious they will share the information with other researchers and the research ethics committee (the committee which decides whether research studies are safe to carry out). A decision will then be made about whether it is safe to continue with the study.



This means making sure that you can't be identified from information which you give during a research study. Information that could identify you, includes your name, address, post code, date of birth, hospital or NHS number. Sometimes an ID number will be used instead of your name. This means that it is possible to link the medical information back to you if necessary (if you are taken ill during the study for example). For some other studies your name and any other information which could identify you is permanently removed from your medical information. This means that there is no way that the information could ever be linked back to you.


Baseline information

This is medical information which researchers will collect about you before a clinical trial begins. This will vary from study to study, it might be blood tests or it could be a questionnaire completed by you about how your medical condition affects your everyday life. This information is necessary so that at the end of the study researchers can measure any good or bad effects which the study treatment has had on you.


Blind study

For certain studies, patients are divided into groups receiving different treatments. A blind study is one where patients do not know which of the study treatments they are receiving. (see also double blind)


Clinical trial

Research studies which test new medical treatments on human beings, are known as clinical trials. See clinical trials section for more information on this type of study.



Researchers are required to keep all your personal details confidential. This means not sharing information about you with anyone who is not involved in the study. The researchers should be able to tell you how they plan to do this.


Controlled trial

A control group is a group of people who are involved in a research study but who do not receive the new study treatment. They might receive the existing treatment for their condition, a placebo (a dummy pill) or no treatment at all. The group receiving the study treatment will be compared to the control group to find out how successful the treatment is.



Any information researchers collect from you is known as data.


Double blind study

A study where neither the patient nor the doctor know which treatment the patient is receiving. In this case only the person organising the study will know who is receiving what treatment and in an emergency they would be able to let doctors know this quickly.


Eligibility criteria

These are rules used by researchers to decide which patients to include or exclude from a study. For example a researcher may want to study only patients in a particular age range. You might also be unable to take part in a study because of another medical condition which you have or because you are taking other medication.


Genetic research

Research looking at genes and how characteristics including ill health and disease are passed on from generation to generation. See section on tissue donation and genetic research for more information.


Informed consent

This is the consent you give, in writing, once a study has been fully explained to you. Your consent is only valid if you have had satisfactory answers to any questions you may have about the research and have been given all the information you require.


Laboratory study

This is an experimental study carried out in a laboratory. It may be the early stages of research into a new treatment, which needs to be tested thoroughly before it can be used on people. You may be asked to donate tissue for this kind of study.


Observational study

A study where researchers monitor your health while you are receiving a particular treatment or medication. This is different from a clinical trial because you are not being asked to use a new treatment, you are simply being monitored as you continue on your normal course of treatment.


Outcome measures

Outcome measures are ways of measuring the success of a new treatment. For example an outcome measure could be to find out whether a new medicine reduces blood pressure. In this case researchers would take measurements of your blood pressure before and after treatment to see if this had happened.


Peer review

This means that before the study starts the researcher gives all the details to a chosen expert who is asked to give their independent opinion of the study. They will look particularly at whether the study is set up in a way which will produce useful results.



A placebo is a 'dummy' inactive pill or medicine which is made to look the same as the study drug. This means that researchers can compare the effects of the real drug against the effects of taking the dummy drug.


Principal investigator

This is the title given to the researcher with overall responsibility for a study. This might not be the same person that you have spoken to most about the study.



This is a detailed plan of exactly what will happen during the research study and who can take part. The protocol is important because other doctors must be able to understand exactly how the research was carried out so they can know whether to trust the findings before using the treatment on other patients.


Prevention studies

These are long term studies which look at ways of preventing ill health, possibly through vaccines, lifestyle changes or medicine.



This is another name for a research study. There are many different types of research project ranging from questionnaires to clinical trials.


Quality of life study

This is a study looking at the effect of a condition or a treatment on a patient's general well being and day-to-day life.



This is the process of dividing research subjects into different treatment groups. This will often be done randomly, possibly using a computer so that neither you nor the researcher know which group you have been put in.


Research ethics committee

Research involving human participants must be approved by an independent research ethics committee before going ahead. Four ethics committees review research at WAHT. They will consider whether the rights of the research subjects are protected and make sure that the study will not knowingly harm their health or interests. They can ask for changes to be made to the study protocol before the research can go ahead.


Research subject

The term used to describe a person who is taking part in a research study.


Sample of tissue

This means anything taken from you as part of a medical investigation or procedure. This could be blood from a blood test, a urine sample, biopsy or even a whole organ (eg spleen, bile duct or kidney) which has been removed during an operation.


Side effects

This means any effect which a treatment can have on a patient other than the one it is prescribed for. For example a hayfever tablet may get rid of hayfever symptoms but may also cause unwanted drowsiness.


Standard treatment

This is the term for whatever treatment is currently in common use for a particular disease or condition. Research studies will often involve testing a new treatment against the standard treatment, to see which is most effective.


Study arm

In some clinical trials, patients will be split into two or more groups each receiving a different treatment. These groups are known as study arms and these groups will then be compared to find out which treatment works best.



Treatment is the term used for any medical procedure carried out during research. This could be in the form of pills, medicine, injections, scans or physiotherapy among others.