Glossary

Term	Explanation
Adverse event (AE)	Any untoward medical occurrence in a person participating in a research trial who has been given a treatment, thought the occurrence is not necessarily caused by the treatment.
Aetiology/etiology	The cause(s) and/or origin of disease.
Body Mass Index (BMI)	A measure to help decide if adults are a healthy weight or underweight, overweight or obese. It is defined as weight in kilograms divided by the square of height in metres (kg/m²).
Case reports/Case studies/Case series	Detailed descriptions that explain what happened to one person (case report) or a small group of people (case series) when they were treated or observed in real clinical practice. They are used to highlight rare, unusual or new medical features or patterns that that doctors have seen to potentially help generate ideas for future research.
Childhood Acute Neuropsychiatric Syndromes (CANS)	A broad category used to describe the sudden and dramatic onset of neuropsychiatric symptoms in children. These may include obsessive-compulsive behaviours, severe eating problems and other emotional, cognitive, or movement-related symptoms. These symptoms can start quickly and follow different patterns over time. Alternative term proposed for PANS (Paediatric Acute-Onset Neuropsychiatric Syndrome).
Clinical Trial Registration	Recording key information about a health research study before it starts, in a public registry. This information typically includes the purpose of the trial, who is taking part, what will be done, and what outcomes will be measured. Registering trials helps make research more transparent and accessible to the public, healthcare professionals and researchers.
Coding	The process of labelling key features of included studies in an evidence and gap map, so that all the research can be organised and compared. It involves systematically recording characteristics which makes it possible to group studies by theme or type.
Conference Abstract	An abbreviated version of a research paper or project that is presented at an academic conference. These abstracts usually include an introduction, a methods section, the results of the research, and a conclusion. These have been subject to minimal peer review (the evaluation of scientific, academic, or professional work by others working in the same field) and so should be considered less reliable sources of information that other article types.
Cross-sectional study	Observational studies that look at data from a group of people at a single point in time. It is often used to describe how common a condition or characteristic is and to explore relationships between factors. Since it does not follow people over time, it cannot show cause and effect.
Empirical Research	Research that is based on real-world observations or data, rather than theory or opinion. It involves collecting and analysing information that can be tested or repeated by others.
Evidence and Gap Map (EGM)	An interactive tool where research on a particular topic is organised and displayed so that it is easy for researchers, policymakers, and interest-holders to see where evidence already exists and where important gaps remain.
Filter	A filter is a tool within evidence and gap maps to narrow down studies shown based on selected criteria, such as study type, population, or setting. Filters help explore specific parts of the evidence more easily.
Gastrointestinal	Related to the gastrointestinal (GI) system which includes the mouth, throat, oesophagus, stomach, small intestine, large intestine, rectum, and anus.
Glucagon like peptide 1 receptor agonists (GLP-1 RAs)	A family of medication also known as GLP-1 analogues. These drugs increase hormones called 'incretins', which help the body make more insulin, reduce the amount of sugar the liver produces and slow digestion speed. They also reduce appetite. Examples include semaglutide (aka Wegovy, Ozempic), and tirzepatide (aka Mounjaro).
Intravenous Immunoglobulin Therapy (IVIg)	A treatment made from antibodies collected from donated human blood plasma. It is commonly used to treat inflammatory and neurological conditions.
Journal Article	A written research paper published in a journal. Journals share new research findings, reviews, or discussions on specific topics and are usually written by researchers for academics and other interest holders. Articles are often reviewed by experts before publication to check their quality and accuracy.
Living network meta-analysis (NMA)	A living network meta-analysis involves continually or regularly repeating the steps of a network meta-analysis (see below) to maintain an ‘up to date’ report of the most current evidence.
Network meta-analysis (NMA)	A network meta-analysis is a way of comparing the effectiveness of multiple different treatments at the same time, even if they haven’t been tested head-to-head in a trial. A network meta-analysis can give us more information and better estimates of the effects of each treatment than a single comparison, and it can also help us rank the treatments according to how effective or safe they are.
Overweight/Obesity	Overweight means having a BMI above the healthy range. For people of White heritage, a BMI: below 18.5 is underweight between 18.5 and 24.9 is healthy between 25 and 29.9 is overweight of 30 or over is obese. Black, Asian and some other minority ethnic groups have a higher risk of developing some long-term conditions such as type 2 diabetes with a lower BMI. People from these groups with a BMI of: 23 or more are at increased risk (overweight) 27.5 or more are at high risk (obese).
Paediatric Acute-Onset Neuropsychiatric Syndrome (PANS)	A clinical condition which often presents very suddenly, with obsessive-compulsive disorder (OCD) or severe eating restrictions, with at least two other symptoms from the PANS PANDAS symptom list. These may include anxiety, mood changes, sensory sensitivity, movement disorders, worsening school performance, behavioural regression, urinary symptoms and/or sleep problems. What are PANS and PANDAS? - PANS PANDAS UK
PANS/PANDAS	A term used to refer collectively to Paediatric Acute-Onset Neuropsychiatric Syndrome (PANS) or Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS), where findings or discussions apply to one or both conditions.
Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS)	A subset of PANS with a temporary association between a Group A streptococcal infection (GAS), more commonly known as ‘strep’, and symptom onset. Major symptoms include OCD and/or tics, which may present very suddenly and very severely, often in childhood. Symptoms may follow relapsing/remitting course (where symptoms appear to get better before getting worse periodically). It is often accompanied by similar symptoms to PANS (anxiety, mood changes, sensory sensitivity, movement disorders, worsening school performance, behavioural regression, urinary symptoms and sleep problems). What are PANS and PANDAS? - PANS PANDAS UK
Paediatric Infection-Triggered Autoimmune Neuropsychiatric Disorders (PITANDS)	A condition that describes the sudden exacerbation obsessive compulsive and/or tic symptoms in response to an auto-immune infection.
Peer review	The process of evaluation of academic research by experts in the field, to access the rigour and strength of a piece of research. It is common process in the assessment of work for journal publication.
Placebo	An inactive substance or procedure given to a person participating in a research study, usually to compare its effects with those of a real drug or other treatment. Placebos are used in trials to make sure people in the trial don’t know whether they have been given the treatment being researched or not. Placebos should be indistinguishable to the patient from the active treatment.
Plasmapheresis	Therapies that involves the removal of antibodies or pathogens from the patient’s plasma. There are different types of plasmaphereses including Therapeutic Plasma Exchange (TPE), lipodoapheresis and rheopheresis.
PROGRESS-PLUS	A framework of criteria which identifies characteristics that may influence health opportunities and outcomes. ‘Progress’ refers to: place of residence; race/ethnicity/culture/language; occupation; gender/sex; religion; education; socioeconomic status; social capital. ‘Plus’ refers to: personal characteristics associated with discrimination (e.g. age, disability); features of relationships (e.g. smoking parents); time-dependent relationships (e.g. when leaving hospital or other instances where a person may be temporarily at a disadvantage). PROGRESS-Plus \| Cochrane Equity
Qualitative research	Qualitative methods of research are scientific methods which focus more on the meaning of different aspects of people’s lives, and on their accounts of how they understand their own and others’ behaviours and beliefs. They include interviews, observation and surveys. Qualitative research – UKRI
Randomised controlled trial (RCT), also written as ‘trial’	A type of experimental study where participants are randomly placed in different groups, for example a group receiving a treatment (i.e. GLP-1 RA) and a group receiving a control condition (i.e. placebo). This allows two or more groups of people to be compared in a way that reduces bias.
Retrospective study	A type of observational study design which analyses past events through the use of records and previously collected data.
Scoping review	A scoping review is a process that systematically identifies and collates research available on a specific topic, to understand the amount and type of research that exists related to that topic.
Serious adverse event (SAE)	Any untoward medical occurrence during a trial that: results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, required intervention to prevent permanent impairment or damage, results in persistent or significant disability/incapacity, or during pregnancy/prior to conception may result in adverse outcomes to the child
Systematic Review	An evidence synthesis type that involves the use rigorous and reproducible methods to identify, collect and synthesise the available data on certain topic; with the use of strict criteria and procedures to reduce bias.
Therapeutic Plasma Exchange (TPE)	A therapeutic treatment and type of plasmapheresis that involves separating the plasma from the blood, discarding it and adding back a replacement fluid containing red blood cells plasma or albumin. This is achieved by passing the patients' blood through an apheresis machine.
Type 2 Diabetes	Type 2 diabetes is a condition that happens because of a problem in the way the body regulates and uses sugar as a fuel. That sugar also is called glucose. This long-term condition results in too much sugar circulating in the blood. Eventually, high blood sugar levels can lead to disorders of the circulatory, nervous and immune systems. Type 2 diabetes - Symptoms and causes - Mayo Clinic
Usual care	A group of participants in a research study, such as a randomised controlled trial, may be given the usual care instead of the drug or a placebo. This means they access the care that is normally given for the issue or health condition being researched in the study, so that the new drug or care being researched can be compared to the existing options for care.
Patient and public involvement and engagement (PPIE)	Involvement is a process of carrying out research with, or by, members of the public. It is an active partnership between researchers and those who the research affects (such as patients, potential patients, carers, and general healthcare service users). Meanwhile engagement is a process of sharing information and knowledge about research to the patients and the public. For example, awareness of research through television media or social media. Patient & public involvement & engagement