Key definitions for the REACT study
Whether people consider something (such as a coronavirus testing kit) to be appropriate for the purpose that it is to be used for. This can be measured by counting how many people would be willing to perform a test, and whether they would do it again if asked in future.
How close a test result is to the actual value.
Substances in the blood that the body’s immune system produces to fight an infection, such as the virus that causes COVID-19. Antibody tests are performed to understand if someone has already had COVID-19 and recovered.
Any substance, for example the virus that causes COVID-19, that could cause harm to the body and that the immune system recognises as a potential threat. Antigen tests are performed to understand if someone is currently infected with the virus that causes COVID-19.
A group of individuals who are taking part in a research study.
This is where COVID-19 is spreading within a particular part of a population.
“Enzyme-Linked Immunosorbent Assay” is a type of lab-based test. Scientists are using this method to check whether coronavirus antibodies are present in a blood sample.
A test result that wrongly identifies a person as not having COVID-19, or not having antibodies to the virus that causes this infection, when they do.
A test result that wrongly identifies a person as having COVID-19, or having antibodies to the virus that causes this infection, when they do not.
An analysis of how practical or easy it is to achieve a desired outcome.
Immunoglobulin G (IgG) is a type of antibody (see Antibody definition) detected by COVID-19 antibody tests. It’s the most common type of antibody found in the blood. They are typically long-lasting to provide prolonged immunity (see Immunity definition) against a disease. However, research is still being carried out to understand if antibodies can protect people from getting COVID-19 again and, if so, how long they last.
Immunoglobulin M (IgM) is a type of antibody (see Antibody definition) detected by COVID-19 antibody tests. It’s the first type of antibody that the body produces when launching an attack against an infection to provide short-term protection, but levels typically decline once the infection has gone.
The immune system’s ability to prevent or protect against a particular infection.
A device to prick your finger and create a drop of blood for a test.
Lateral Flow Test (LFT) / Lateral Flow Immunoassays (LFIA)
These are small testing devices that are used to find out whether someone has antibodies to the virus that causes COVID-19 in their blood. They have an absorbent pad at one end where a blood drop is placed, and the result of the test is shown at the other end.
For COVID-19, this means the proportion of people in a particular area or population who are currently infected at a specific time.
The R number, or reproduction rate is the average number of people that a person infected with the coronavirus will pass the infection on to.
RT-PCR (or PCR)
Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a lab test that looks for the presence of coronavirus genetic material.
Severe acute respiratory syndrome coronavirus 2 is the virus that causes the disease COVID-19.
How well a test can correctly identify people who have the coronavirus or coronavirus antibodies. These are called ‘true positives’.
The number of people in a population who have a specific marker in their blood, in this case antibodies for SARS-CoV-2.
The part of your blood that is not involved in clotting. It is where antibodies are found, among other things such as hormones, but there are no white or red blood cells.
How well a test can correctly identify people who don’t have the coronavirus or coronavirus antibodies. These are called ‘true negatives’.
A type of immune cell (white blood cell) that plays a role in fighting infection.
The cut-off point used when analysing test results. Below this level, tests are interpreted as a negative result, and above this level, tests are interpreted as a positive result.
How easy it is for people to perform a task, such as an antibody test, correctly.
Validity (or Validation)
How reliable something is, such as an antibody test.