Search scientific, clinical-trial and regulatory terms used across WhichPeps. Each definition explains what the term means and why misreading it could distort the evidence.
This glossary is generated from /glossary-data.json so the same definitions can later power search results, inline explanations and tooltips without manually duplicating wording across the site.
· Also: AE
Plain English: An unwanted medical occurrence after exposure to a medicine or intervention; it does not by itself prove the intervention caused it.
Technical: A medical occurrence temporally associated with use/exposure, whether or not considered causally related.
Why it matters on WhichPeps: Prevents “reported after treatment” being misread as “caused by treatment”.
Plain English: A substance that activates a receptor or biological target.
Technical: A ligand that binds a receptor and produces a biological response.
Why it matters on WhichPeps: A mechanism can be real without proving a useful clinical benefit.
· Also: Alternate name, Synonym
Plain English: An alternate name or search term that refers to the same canonical entity in WhichPeps.
Technical: A non-canonical identifier mapped to the same canonical entity record. An alias does not create a second scientific record.
Why it matters on WhichPeps: Brand names, development codes, common shorthand and spelling variants can all lead to one evidence page without duplicating the evidence.
Plain English: A building block used to make peptides and proteins.
Technical: Organic compounds containing amino and carboxyl functional groups; amino-acid residues join through peptide bonds in peptides/proteins.
Why it matters on WhichPeps: Helps explain what a peptide chain is made from.
· Also: Analog
Plain English: A molecule made to resemble another molecule while changing one or more structural features.
Technical: A compound with structural similarity to a reference compound; biological properties can still differ.
Why it matters on WhichPeps: Evidence for one analogue cannot automatically be transferred to another.
Plain English: A substance that reduces or blocks a receptor response.
Technical: A ligand/substance that blocks or reduces an agonist-induced receptor effect.
Why it matters on WhichPeps: Mechanism labels do not tell you whether a clinical outcome is beneficial.
Plain English: A specific use that a regulator has authorised for a particular medicine/product.
Technical: The disease, population and use conditions included in a marketing authorisation or product label.
Why it matters on WhichPeps: Approval for one use does not automatically mean approval for other uses.
Plain English: A medicine authorised by a named regulator for one or more specific uses.
Technical: A medicinal product with a current marketing authorisation/licence in the jurisdiction being discussed.
Why it matters on WhichPeps: WhichPeps always states the regulator, product/formulation and indication where relevant.
· Also: BA
Plain English: How much and how quickly an active ingredient becomes available at the site of action after administration.
Technical: The rate and extent to which an active ingredient or active moiety is absorbed and becomes available at the site of drug action.
Why it matters on WhichPeps: Formulation and route can materially change exposure even when the active ingredient has the same name.
Plain English: A measurable biological characteristic used as an indicator of a process, condition or response.
Technical: A defined characteristic measured as an indicator of normal biological processes, pathogenic processes or responses to an exposure/intervention.
Why it matters on WhichPeps: A biomarker change is not automatically the same as feeling better, living longer or avoiding disease.
· Also: Masking
Plain English: A study method that keeps one or more groups unaware of treatment assignment.
Technical: A design feature intended to reduce expectation and assessment bias by concealing allocation from participants, investigators and/or assessors.
Why it matters on WhichPeps: Lack of blinding can make subjective outcomes more vulnerable to bias.
Plain English: The commercial name of a specific medicinal product.
Technical: A proprietary name attached to a product/formulation; it is not automatically a separate scientific molecule.
Why it matters on WhichPeps: A brand search should resolve to the canonical active compound while preserving formulation and indication differences.
Plain English: The main name WhichPeps uses for one scientific entity.
Technical: The stable preferred entity label attached to one canonical record and ID.
Why it matters on WhichPeps: It prevents duplicate evidence pages when users search by brand, code, nickname or spelling variant.
Plain English: A record of material evidence or editorial changes over time.
Technical: A provenance log describing changed fields/wording, reason, source and date where material.
Why it matters on WhichPeps: It makes evidence updates auditable instead of silently rewriting the past.
Plain English: Whether a result is large or meaningful enough to matter in real-world health or function.
Technical: The practical or patient-important importance of an observed effect, distinct from whether a statistical test crosses a threshold.
Why it matters on WhichPeps: A statistically significant result can still be too small or indirect to matter clinically.
Plain English: A research study in people that prospectively evaluates a health-related intervention or question.
Technical: A prospective human study in which participants are assigned or exposed according to a protocol to evaluate biomedical or health-related outcomes.
Why it matters on WhichPeps: Human evidence varies greatly by phase, design, sample size, comparator and endpoint.
Plain English: What an intervention is compared against in a study.
Technical: A control condition such as placebo, standard care, active treatment or another dose/formulation.
Why it matters on WhichPeps: Without knowing the comparator, “better” or “changed” can be misleading.
· Also: CI
Plain English: A range around an estimate that expresses statistical uncertainty.
Technical: An interval calculated from sample data that, under the chosen statistical procedure, reflects uncertainty around an estimated effect.
Why it matters on WhichPeps: Wide intervals often signal imprecision even when the headline estimate looks large.
Plain English: The amount used in a specific study or authorised label; it is not a WhichPeps recommendation.
Technical: The protocol-defined or label-defined quantity, frequency and schedule for a particular population, route and formulation.
Why it matters on WhichPeps: Prevents descriptive research doses being converted into personal instructions.
Plain English: How well an intervention produces a defined outcome under the conditions of a study.
Technical: The extent to which an intervention achieves a specified outcome in a defined study context.
Why it matters on WhichPeps: Efficacy in a trial does not automatically generalise to every population, product or real-world use.
· Also: European Medicines Agency
Plain English: The EU agency that supports scientific evaluation and monitoring of medicines in the European Union.
Technical: The European Medicines Agency coordinates scientific assessment for centrally authorised medicines and pharmacovigilance functions in the EU.
Why it matters on WhichPeps: EU authorisation must be kept separate from UK and US status.
Plain English: The outcome a study is designed to measure.
Technical: A prespecified measurable event or outcome used to assess an intervention.
Why it matters on WhichPeps: A surrogate or biomarker endpoint can be very different from a patient-important outcome.
Plain English: WhichPeps’ structured judgement about how strong and applicable the available evidence is.
Technical: A transparent site classification based on evidence type, design, directness, replication and limitations; not simply study count or development phase.
Why it matters on WhichPeps: It prevents “many studies” or “Phase III” being treated as automatic proof.
· Also: U.S. Food and Drug Administration
Plain English: The US federal regulator responsible for medicines and other regulated medical products.
Technical: The U.S. Food and Drug Administration evaluates and regulates drug/biologic products under US law.
Why it matters on WhichPeps: FDA status is US-specific and should not be presented as UK or EU status.
Plain English: The specific physical product or preparation used to deliver an active ingredient.
Technical: The composition and dosage form in which an active substance is presented, including excipients and delivery characteristics.
Why it matters on WhichPeps: Different formulations can have different absorption, stability, evidence and regulatory status.
Plain English: The time it takes for the amount or concentration of a substance in the body to fall by roughly half.
Technical: A pharmacokinetic parameter describing decline in drug amount/concentration under defined conditions.
Why it matters on WhichPeps: It helps interpret exposure and study schedules but does not itself tell someone what dose to take.
Plain English: Evidence collected from people rather than laboratory systems or animal models.
Technical: Clinical, observational, pharmacology or other human-participant evidence, classified further by design and question.
Why it matters on WhichPeps: “Human” does not automatically mean strong; a two-person pilot and a large randomised trial carry very different weight.
Plain English: Research performed outside a living organism, often in cells or laboratory systems.
Technical: Experiments performed in an artificial laboratory environment rather than within an intact organism.
Why it matters on WhichPeps: A laboratory effect does not prove the same outcome occurs safely or meaningfully in people.
Plain English: Research performed in a living organism.
Technical: Experiments conducted within a living organism; on WhichPeps the species/population must still be stated.
Why it matters on WhichPeps: Animal in-vivo evidence must remain separate from human evidence.
· Also: IM
Plain English: Delivery by injection into muscle tissue.
Technical: A parenteral route in which a medicinal product is injected into muscle.
Why it matters on WhichPeps: Evidence and formulation requirements for IM use do not automatically transfer to SC or IV use.
· Also: IV
Plain English: Delivery directly into a vein.
Technical: A parenteral route delivering a product into the venous circulation.
Why it matters on WhichPeps: IV exposure, sterility requirements and safety context differ from other routes.
Plain English: Still under study and not the same as approved for clinical use.
Technical: A drug, biologic or use being studied in research/development without a current authorisation for that use in the jurisdiction discussed.
Why it matters on WhichPeps: Prevents active research from being mistaken for established clinical availability.
· Also: µg, microgram
Plain English: A unit of mass equal to one millionth of a gram.
Technical: 1 microgram (µg or mcg) = 0.001 mg.
Why it matters on WhichPeps: Confusing mg and micrograms creates a 1,000-fold unit error; WhichPeps treats units as descriptive data, not dosing instructions.
· Also: Mechanism
Plain English: How a substance is thought or shown to interact with biological targets or processes.
Technical: The biochemical/physiological interaction by which an intervention produces downstream effects.
Why it matters on WhichPeps: A plausible mechanism is not the same as a demonstrated clinical benefit.
Plain English: A statistical analysis that combines results from multiple studies when they are sufficiently comparable.
Technical: A quantitative evidence-synthesis method that pools study-level or participant-level estimates under specified assumptions.
Why it matters on WhichPeps: A pooled result can still inherit bias, heterogeneity and limitations from the underlying studies.
· Also: milligram
Plain English: A unit of mass equal to one thousandth of a gram.
Technical: 1 mg = 0.001 g = 1000 micrograms (mcg/µg).
Why it matters on WhichPeps: A unit is only a quantity; it does not make a studied dose appropriate for an individual.
· Also: Medicines and Healthcare products Regulatory Agency
Plain English: The UK regulator for medicines and medical devices.
Technical: The Medicines and Healthcare products Regulatory Agency regulates medicines and medical devices in the United Kingdom within its legal remit.
Why it matters on WhichPeps: WhichPeps is UK-operated, so UK legal/status language must not be inferred solely from US sources.
Plain English: A human study that observes exposures and outcomes without randomly assigning the intervention.
Technical: A study in which investigators observe naturally occurring exposures/treatments and outcomes rather than prospectively randomising treatment.
Why it matters on WhichPeps: Associations can be informative but are more vulnerable to confounding and do not by themselves prove causation.
· Also: Off-label use
Plain English: Use of an approved medicine outside the specific indication or conditions in its authorisation.
Technical: Prescribing/use of an authorised medicinal product in a way that differs from the licensed indication, population, dose, route or other authorised conditions.
Why it matters on WhichPeps: Off-label does not mean the medicine itself is unapproved, and it must not be confused with an unlicensed product.
Plain English: Delivery by mouth and swallowing.
Technical: An enteral route in which a product is administered via the mouth for gastrointestinal absorption or local effect.
Why it matters on WhichPeps: Oral bioavailability and formulation can differ substantially from injectable routes.
· Also: PD
Plain English: What a medicine or compound does to the body.
Technical: The magnitude and time course of pharmacological effects and their relationship to exposure.
Why it matters on WhichPeps: A measurable biological effect may still be only a biomarker or mechanism rather than a clinical benefit.
· Also: PK
Plain English: How a medicine or compound is absorbed, distributed/modified and removed over time.
Technical: The time course of drug exposure, commonly including absorption, distribution, metabolism and elimination.
Why it matters on WhichPeps: PK helps explain route/formulation differences and why two products cannot be assumed equivalent.
· Also: Phase 1
Plain English: An early human trial phase focused mainly on safety, tolerability, pharmacology and dose-ranging questions.
Technical: First-in-human/early clinical development studies that characterise safety, side effects, PK/PD and administration under a protocol.
Why it matters on WhichPeps: Phase I is not proof that a treatment works for a disease.
· Also: Phase 2
Plain English: A clinical development phase that explores efficacy signals and continues safety evaluation in a target condition/population.
Technical: Controlled or uncontrolled studies designed to estimate activity/efficacy and refine dose/regimen while collecting safety data.
Why it matters on WhichPeps: A positive Phase II trial can still be too small or preliminary to establish broad benefit.
· Also: Phase 3
Plain English: A later clinical development phase that usually compares an intervention in larger populations to establish benefit-risk for defined uses.
Technical: Large confirmatory studies intended to provide evidence about efficacy and safety across relevant populations/conditions.
Why it matters on WhichPeps: Phase III status is a development stage, not an evidence grade or regulatory approval.
Plain English: An inactive or non-specific comparison made to look and be given like the intervention being tested.
Technical: A control intervention without the active treatment component, used to help distinguish treatment effects from expectation/context.
Why it matters on WhichPeps: Placebo control can improve causal interpretation, especially for subjective outcomes.
Plain English: Research conducted before or outside therapeutic human testing, commonly in laboratory or animal models.
Technical: Nonclinical evidence from in vitro, ex vivo and/or animal studies used to explore biology, toxicology and candidate effects.
Why it matters on WhichPeps: Preclinical findings cannot establish human efficacy or human dose.
· Also: POM
Plain English: A UK legal supply classification requiring a prescription from an authorised prescriber.
Technical: One of the UK medicine legal classifications under the Human Medicines Regulations; POMs require prescription and controlled supply.
Why it matters on WhichPeps: WhichPeps must not turn public evidence pages into advertisements for POMs.
· Also: Primary endpoint
Plain English: The main prespecified outcome a study is designed to evaluate.
Technical: The principal outcome measure used to answer the primary research question and often underpin sample-size planning.
Why it matters on WhichPeps: Secondary or exploratory findings should not be presented as if they were the study’s main test.
· Also: Randomization
Plain English: Assignment of study participants to groups by chance.
Technical: A method that uses a chance process to allocate participants, aiming to reduce systematic differences between groups.
Why it matters on WhichPeps: Randomisation strengthens causal comparisons but does not fix poor measurement, attrition or underpowered design.
· Also: RCT, Randomized controlled trial
Plain English: A study where participants are assigned to groups by chance to compare an intervention with a control.
Technical: A controlled interventional design using random allocation; blinding and comparator choice vary by protocol.
Why it matters on WhichPeps: Often stronger for causal questions, but quality, size and applicability still matter.
Plain English: A biological molecule that can bind a signalling substance or drug and trigger or alter cellular responses.
Technical: A molecular target, commonly a protein, whose ligand binding changes signalling or function.
Why it matters on WhichPeps: Receptor activation or blockade is mechanism evidence, not automatic proof of a patient benefit.
Plain English: The formal legal/authorisation state of a product or use in a specific jurisdiction.
Technical: A jurisdiction-, product-, formulation- and indication-specific status determined by the relevant regulator/legislation.
Why it matters on WhichPeps: “Approved in the US” cannot be silently turned into “approved everywhere”.
· Also: Development code
Plain English: A sponsor/developer identifier used for a compound during research and development.
Technical: An alphanumeric development identifier that may precede or coexist with an INN/generic name.
Why it matters on WhichPeps: Search should resolve the code to the same canonical evidence record rather than create a duplicate page.
· Also: Evidence reviewed date
Plain English: The date the scientific evidence behind a page was last reviewed.
Technical: An editorial provenance field distinct from the date a webpage template or layout was updated.
Why it matters on WhichPeps: Readers need to know how current the evidence review is.
· Also: Route
Plain English: How a substance is delivered, such as oral, subcutaneous, intravenous or intramuscular.
Technical: The pathway by which a drug/product enters the body; route can materially change exposure, formulation requirements and safety.
Why it matters on WhichPeps: Evidence from one route should not automatically be transferred to another.
Plain English: Information that raises a new or changed concern about a possible adverse effect.
Technical: A signal is information suggesting a potentially causal association or new aspect of a known association that warrants further evaluation.
Why it matters on WhichPeps: A signal is not automatically proof of causation, but it should not be hidden.
· Also: n
Plain English: The number of participants, animals, samples or observations included in an analysis.
Technical: The number of analysable experimental units contributing to an estimate or comparison.
Why it matters on WhichPeps: Very small samples can produce unstable estimates and miss uncommon harms.
Plain English: The traceable origin of a claim, data point or status statement.
Technical: The linked chain from a public summary back to a structured evidence record and primary/regulatory source.
Why it matters on WhichPeps: It lets readers verify where a statement came from and what evidence type supports it.
· Also: p-value threshold
Plain English: A statistical result indicating that observed data are relatively incompatible with a specified null model at a chosen threshold.
Technical: A property of a statistical test/estimate, often summarised using p-values or confidence intervals; it does not measure clinical importance.
Why it matters on WhichPeps: A statistically significant result can still be small, biased, indirect or clinically unimportant.
· Also: SC, SubQ
Plain English: Delivery into the tissue layer beneath the skin.
Technical: A parenteral route in which a product is injected into subcutaneous tissue.
Why it matters on WhichPeps: Route-specific trial or label evidence should not be silently applied to oral, IV, IM or other formulations.
Plain English: A measurement used instead of directly measuring how a person feels, functions or survives.
Technical: A biomarker or intermediate endpoint intended to predict clinical benefit or harm.
Why it matters on WhichPeps: Surrogate improvement does not automatically prove meaningful clinical benefit.
Plain English: A structured review that uses predefined methods to find, assess and synthesise relevant studies.
Technical: An evidence synthesis following explicit eligibility, search, appraisal and synthesis methods.
Why it matters on WhichPeps: The review cannot be stronger than the quality, directness and completeness of the included studies.
· Also: Unlicensed medicine
Plain English: A medicinal product that does not hold the relevant marketing authorisation for the jurisdiction/product being discussed.
Technical: A medicine supplied without a marketing authorisation for that product/use under specific legal/professional arrangements; rules are jurisdiction-specific.
Why it matters on WhichPeps: It must not be described as “approved” or promoted like an authorised medicine.
Plain English: A planned period between treatments or study phases that allows effects/exposure from the earlier intervention to diminish.
Technical: A protocol-defined interval intended to reduce carry-over from a previous treatment/exposure.
Why it matters on WhichPeps: In crossover studies, an inadequate washout can distort the comparison.
The definitions above explain research terminology. WhichPeps evidence-strength labels describe the current evidence for a particular entity/outcome and should not be confused with trial phase or regulatory approval.
Read the evidence methodology