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IVD classification — List A · List B · Self-test · General

Regulatory basis

IVD classification under UK MDR 2002 is governed by Part III and its Annex II (Lists A and B). Self-test device requirements are in Annex III of Part III. Part III of UK MDR 2002 is derived from the former EU IVDD 98/79/EC and is distinct from the EU IVDR 2017/746 classification system that applies in Northern Ireland.

Disclaimer

This site provides general information only and does not constitute legal or regulatory advice. Always consult the UK MDR 2002 Part III Annex II text and MHRA guidance before making IVD classification decisions.

The IVD classification system​

Unlike general medical devices — which use the Schedule 2 classification rules to assign Classes I through III — IVD medical devices under Part III of UK MDR 2002 use a different, list-based classification approach inherited from the former EU IVDD 98/79/EC.

The system has four categories:

CategoryRiskUKAB required?Basis
Annex II List AHighestYes — design dossier + production QAExplicitly listed in Annex II List A
Annex II List BSignificantYes — type-examination or QMSExplicitly listed in Annex II List B
Self-test devicesVariableYesIntended for lay person home use
General IVDsLowest (regulated)NoAll IVDs not in Lists A, B, or Self-test

The system is not purely risk-based in the analytical sense — it reflects the political and scientific consensus at the time of the original IVDD (1998) about which diagnostic tests warranted enhanced scrutiny.

Contrast with EU IVDR

The EU IVDR 2017/746, which applies in Northern Ireland, replaced this list-based system with a fully risk-based classification (Classes A, B, C, D) using seven classification rules. Many IVDs that remain "General" under UK MDR 2002 Part III have been upclassified to Class B or Class C under EU IVDR. Manufacturers serving both markets must manage both classification systems.

Annex II List A — highest-risk IVDs​

What makes a device List A?​

List A devices are those where diagnostic errors could have catastrophic consequences — typically affecting blood safety, organ/tissue compatibility, or the detection of life-threatening communicable diseases. The risk is not only to the individual patient but potentially to blood supply safety and public health.

Current List A devices​

Under UK MDR 2002 Part III, Annex II List A currently includes:

Blood-borne pathogen detection:

  • Reagents and reagent products for the detection of HIV 1 and HIV 2
  • Reagents and reagent products for HTLV I and HTLV II
  • Reagents and reagent products for Hepatitis B (HBsAg, anti-HBc, anti-HBs)
  • Reagents and reagent products for Hepatitis C (anti-HCV)
  • Reagents and reagent products for Hepatitis D (anti-HDV)

Blood group determination:

  • ABO blood grouping systems (anti-A, anti-B, anti-A+B)
  • Rh blood grouping reagents: anti-D, anti-C, anti-c, anti-E, anti-e
  • Kell blood group (anti-K) reagents
  • Kidd blood group (anti-Jka, anti-Jkb) reagents
  • Duffy blood group (anti-Fya, anti-Fyb) reagents
  • Reagents for detection of irregular anti-erythrocyte antibodies (cross-matching)

Conformity assessment for List A​

List A IVDs require the most rigorous conformity assessment under UK MDR 2002 Part III:

  1. EC Design Examination (Annex IV equivalent) — the UKAB examines the device design, including analytical and clinical performance data, and issues a Design Examination Certificate
  2. Production Quality Assurance (Annex VII equivalent) — the UKAB audits the manufacturer's production QMS to confirm consistent manufacturing
  3. Alternatively: Full Quality Assurance (Annex VI equivalent) — a single UKAB audit covering both design and production quality systems

The manufacturer then issues a UK Declaration of Conformity and affixes the UKCA mark.

Annex II List B — significant-risk IVDs​

What makes a device List B?​

List B devices are those where diagnostic errors carry significant (though generally less immediately catastrophic) clinical consequences — affecting individual patient management for important conditions, or used in screening programmes where accuracy is critical.

Current List B devices​

Under UK MDR 2002 Part III, Annex II List B currently includes:

Infectious disease screening:

  • Reagents for rubella (anti-rubella IgG/IgM)
  • Reagents for toxoplasma (anti-toxoplasma IgG/IgM)
  • Reagents for cytomegalovirus (CMV) (anti-CMV IgG/IgM)
  • Reagents for Chlamydia trachomatis (antigen detection)
  • Reagents for HTLV III (some formulations)

Neonatal and prenatal screening:

  • Reagents for phenylketonuria (PKU) — used in newborn blood spot screening
  • Reagents for congenital hypothyroidism (TSH) — newborn screening
  • Reagents for congenital adrenal hyperplasia — newborn screening

Tumour markers and endocrinology:

  • Reagents for prostate specific antigen (PSA) — for diagnosis of prostate disease
  • Reagents for human chorionic gonadotropin (hCG) — professional use pregnancy testing

Diabetes management:

  • Blood glucose testing reagents for professional healthcare use
  • Haemoglobin A1c (HbA1c) measurement systems (where specifically listed)

Haematology:

  • Reagents for haemoglobin determination in blood

Conformity assessment for List B​

List B IVDs require UKAB involvement, but through a less intensive route than List A. Options include:

  1. EC Type-Examination (Annex V equivalent) — UKAB examines a representative specimen of the device; followed by production surveillance (Annex V, VI, or VII)
  2. Full Quality Assurance (Annex VI equivalent) — UKAB audits the full QMS covering design and production

The manufacturer issues a UK Declaration of Conformity referencing the UKAB certificate.

Self-test devices​

Definition​

A self-test IVD is one that is specifically designed to be used by lay persons in a non-professional (home) setting, without the involvement of a trained healthcare professional in the testing process.

Self-test status applies regardless of which Annex II list the device's analyte would otherwise fall under. A home HIV test is both a potential List A analyte and a self-test device — the self-test requirements layer on top.

Why self-test devices have additional requirements​

Lay persons operating IVDs without professional training face specific challenges:

  • Correct sample collection (fingerprick blood, urine, saliva)
  • Correct performance of the test procedure
  • Correct interpretation of the result
  • Appropriate action following the result

Self-test devices must be validated for lay use, with usability studies demonstrating that the representative lay population can use the device correctly and interpret results accurately.

Conformity assessment for self-test devices​

Self-test devices require UKAB involvement specifically for the evaluation of their design and performance characteristics related to self-testing. The UKAB must be satisfied that:

  • The device is genuinely usable by lay persons without professional assistance
  • The IFU is written in plain, accessible language appropriate for the intended lay user
  • Sample collection is achievable by a lay person using the described technique
  • Results are clearly presented and interpretable by a lay user

Examples of self-test IVDs​

  • Home pregnancy tests (lateral flow, consumer)
  • Consumer blood glucose monitoring systems
  • Home HIV tests (e.g., OraQuick-type)
  • Home ovulation prediction kits
  • Home urine UTI tests
  • Home cholesterol tests
  • Consumer COVID-19 lateral flow antigen tests

General IVDs​

Definition​

All IVD medical devices that are not listed in Annex II (List A or List B) and not intended as self-test devices are "General IVDs." Despite being the lowest-risk category, they are still medical devices subject to UK MDR 2002 Part III requirements.

Conformity assessment for General IVDs​

General IVDs do not require UK Approved Body involvement. The manufacturer:

  • Self-declares conformity with the Essential Requirements (Schedule 1A, UK MDR 2002 Part III)
  • Prepares a technical file demonstrating conformity
  • Prepares a performance evaluation report
  • Issues a UK Declaration of Conformity
  • Affixes the UKCA mark (or relies on CE marking under transitional acceptance)
  • Registers with MHRA

Examples of General IVDs​

General IVDs constitute the large majority of all IVDs on the market:

  • Most clinical chemistry analysers and reagents (electrolytes, liver function, renal function)
  • Routine haematology analysers (full blood count instruments)
  • Most microbiology culture media
  • Urine dipstick tests for routine urinalysis (non-self-test)
  • Coagulation analysers and reagents (PT/INR, APTT)
  • Blood gas analysers
  • Most immunoassay platforms for analytes not in Lists A or B
  • Specimen collection containers (blood tubes, urine containers, swabs)
  • Calibrators and quality controls for non-List-A/B analytes
  • Laboratory centrifuges, pipettes, and ancillary equipment sold specifically for in vitro examination

Managing two IVD classification systems: GB and EU/NI​

For manufacturers placing IVDs on both the GB market and the EU/NI market, two independent classification determinations are required:

FrameworkClassification systemGoverning regulation
Great BritainList A / List B / Self-test / GeneralUK MDR 2002 Part III (IVDD-derived)
EU and Northern IrelandClass A / B / C / DEU IVDR 2017/746 (new risk-based)

Key impact of EU IVDR on GB-only manufacturers​

Even manufacturers selling only in GB should be aware of EU IVDR because:

  1. Many GB-based manufacturers also serve the EU/NI market
  2. EU IVDR upclassified many previously "General" IVDs to Class B or C, requiring EU Notified Body involvement for EU/NI
  3. MHRA's reform programme may introduce an IVDR-like classification system for GB in future

Mapping between systems​

There is no official one-to-one mapping between UK MDR 2002 Part III categories and EU IVDR classes. However, as a general guide:

UK MDR 2002 Part IIIEU IVDR 2017/746 approximate equivalent
Annex II List AClass C–D (some List A → Class D)
Annex II List BClass B–C
Self-testClass A–C (depends on analyte)
GeneralClass A–B (many formerly General IVDs are now Class B under IVDR)

This mapping is approximate. Each device must be classified independently under each framework.

Official references​

ReferenceDescription
UK MDR 2002, Part III, Annex IILists A and B of higher-risk IVDs
UK MDR 2002, Part III, Annex IIISelf-test device requirements
UK MDR 2002, Part III, Annex IV–VIIConformity assessment procedures for IVDs
UK MDR 2002, Part III, Schedule 1AEssential Requirements for IVDs
EU IVDR 2017/746, Annex VIIIEU IVDR classification rules — applies in NI
MHRA: IVD medical devices guidanceMHRA's IVD regulatory guidance
MHRA: Pre-submission meetingsFor borderline IVD classification queries