Global Harmonization Task Force
Title: Principles of In Vitro Diagnostic (IVD) Medical Devices Classification
Authoring Group: Study Group 1 of the Global Harmonization Task Force
Date: February 9, 2007
Table of Contents
Rationale, Purpose and Scope 5
1.1 Rationale 5
1.2 Purpose 5
1.3 Scope 5
General Principles 8
Recommendations and factors influencing IVD Medical Device Classification 8
7.0 Proposed General Classification System for IVD Medical Devices 9
8.0 The Determination of Device Class 11
9.0 Classification Rules 12
This document was produced by the Global Harmonization Task Force, a voluntary consortium of representatives from medical device Regulatory Authorities and trade associations from around the world. The document is intended to provide non-binding guidance to Regulatory Authorities for use in the regulation of medical devices and has been subject to consultation throughout its development and endorsement by the current Chair.
There are no restrictions on the reproduction, distribution, translation or use of this document however, incorporation of this document, in part or in whole, into any other document does not convey or represent an endorsement of any kind by the Global Harmonization Task Force.
The objective of the Global Harmonization Task Force (GHTF) is to encourage convergence at the global level in the evolution of regulatory systems for medical devices in order to facilitate trade whilst preserving the right of participating members to address the protection of public health by regulatory means considered to be most suitable.
The primary way in which the Global Harmonization Task Force (GHTF) achieves its goals is through the production of harmonized guidance documents suitable for implementation or adoption by member Regulatory Authorities, as appropriate taking into account their existing legal framework, or by nations with developing regulatory programmes.
This guidance document is one of a series that together describe a global regulatory model for medical devices. Its purpose is to assist a manufacturer to allocate its medical device to an appropriate risk class using a set of harmonized principles. Regulatory Authorities have the responsibility of ruling upon matters of interpretation for a particular medical device. Once assigned, such classification will prescribe how the manufacturer will demonstrate that its device complies with other documents in the series and, in particular, with those entitled Essential Principles of Safety and Performance of Medical Devices and Labelling for Medical Devices should it be required or requested so to do by a Regulatory Authority, Conformity Assessment Body, user or third party.
This document should be read in conjunction with the GHTF document on Principles of Conformity Assessment for IVD Medical Devices that recommends conformity assessment requirements appropriate to each of the four risk classes proposed herein. The linked development of documents on classification and conformity assessment are important to ensure a consistent approach across all countries/regions adopting the global regulatory model recommended by the GHTF, so that premarket approval for a particular device may become acceptable globally. Regulatory Authorities who may have different classification procedures are encouraged to adopt this GHTF guidance as the opportunity permits.
This document has been developed to encourage and support global convergence of regulatory systems. It is intended for use by Regulatory Authorities, Conformity Assessment Bodies and industry, and will provide benefits in establishing, in a consistent way, an economic and effective approach to the control of medical devices in the interest of public health.
Regulatory Authorities that are developing classification schemes or amending existing ones are encouraged to consider the adoption of the system described in this document, as this will help to reduce the diversity of schemes worldwide and facilitate the process of harmonization.
The regulatory requirements of some countries do not, at this time, align fully with this guidance.
This guidance document has been prepared by Study Group 1 of the Global Harmonization Task Force (GHTF). Comments or questions about it should be directed to either the Chairman or Secretary of GHTF Study Group 1 whose contact details may be found on the GHTF web page.
Rationale, Purpose and Scope
This guidance document is one of a series that together describe a global regulatory model for medical devices. It provides guidance on the principles of classification of IVD Medical Devices.
Since the inter-relationship between device class and conformity assessment is critical in establishing a consistent approach to premarket approval across all countries/regions, it should be read in conjunction with the GHTF document on Principles of Conformity Assessment for IVD Medical Devices that recommends procedures that may be used to demonstrate that an IVD Medical Device conforms to the Essential Principles of Safety and Performance for Medical Devices The linked development of documents on classification and conformity assessment is important to ensure a consistent approach across all countries/regions adopting the global regulatory model recommended by the GHTF, so that premarket approval for a particular device may become acceptable globally.
The purpose of this document is to
assist a manufacturer to allocate its IVD Medical Device to an appropriate risk class using a set of harmonized classification principles;
base such classification principles on an IVD Medical Device’s intended use ;
allow Regulatory Authorities to rule upon matters of interpretation for a particular IVD Medical Device, when appropriate.
Subsequently, such classification will determine the conformity assessment route as described in the GHTF document on Principles of Conformity Assessment for IVD Medical Devices.
This document applies to all products that fall within the definition of an IVD Medical Device. An IVD Medical Device is defined as a device which, whether used alone or in combination, is intended by the manufacturer for the in-vitro examination of specimens derived from the human body solely or principally to provide information for diagnostic, monitoring or compatibility purposes. This includes reagents, calibrators, control materials, specimen receptacles, software, and related instruments or apparatus or other articles. Note: International reference materials (e.g WHO) and materials used for external quality assessment schemes are excluded.
GHTF final documents
SG1/N012 Role of Standards in the Assessment of Medical Devices.
SG1/N029 Information Document Concerning the Definition of the Term ‘Medical Device’.
SG1/N041 Essential Principles of Safety and Performance of Medical Devices.
SG1/N043 Labelling for Medical Devices.
[To be developed for IVD]
Accessory : An article which, is intended specifically by its manufacturer to:
be used together with a parent device to enable that device to be used in accordance with its intended use as an IVD Medical Device.
or to augment or extend the capabilities of the parent device in fulfilment of its intended use as an IVD Medical Device.
and therefore should be considered an IVD Medical Device.
IVD Medical Device for Self-testing: Any device intended by the manufacturer for use by lay persons.
Examination: Set of operations having the object of determining the value of a property.
Note: In the IVD Medical Device industry and in many laboratories that use IVD Medical Devices, examination of an analyte in a biological sample is commonly referred to as a test, assay or analysis. (Source: ISO 15198:2004)
Harm: Physical injury or damage to the health of people or damage to property or the environment. (Source – ISO/IEC Guide 51:1999 – ISO 14971:2000).
Hazard: Potential source of harm. (Source – ISO/IEC Guide 51:1999 – ISO 14971:2000).
Intended use / purpose: The objective intent of the manufacturer regarding the use of a product, process or service as reflected in the specifications, instructions and information provided by the manufacturer. (Source – 21 CFR 801.4)
Instrument: equipment or apparatus intended by the manufacturer to be used as IVD Medical Device.
IVD Medical Device: A device, whether used alone or in combination, intended by the manufacturer for the in-vitro examination of specimens derived from the human body solely or principally to provide information for diagnostic, monitoring or compatibility purposes. This includes reagents, calibrators, control materials, specimen receptacles, software, and related instruments or apparatus or other articles.
Note: In some jurisdictions, some IVD Medical Devices may be covered by separate regulations
Reagent: chemical, biological or immunological components, solutions or preparations intended by the manufacturer to be used as IVD Medical Devices.
Lay person: individual that does not have formal training in a specific field or discipline (Source - Adapted from the definition of “lay user” in EN 376:2002. (Source: ISO 15197: 2003)
Near patient (testing): Testing performed outside a laboratory environment by a professional other than a laboratory professional , generally near to, or at the side of, the patient.
Risk: Combination of the probability of occurrence of harm and the severity of that harm. (Source – ISO/IEC Guide 51:1999 – ISO 14971:2000)
Self-testing: Testing[examination to align with labelling standard] performed by lay persons.
Specimen receptacle: a device, whether vacuum-type or not, specifically intended by their manufacturers for the primary containment of specimens derived from the human body.
Transmissible agent: An agent capable of being transmitted to a person, as a communicable, infectious or contagious disease.
Transmission: The conveyance of disease to a person.
Regulatory controls are intended to safeguard the health and safety of patients, users and other persons by ensuring that manufacturers of IVD Medical Devices follow specified procedures during design, manufacture and marketing.
The risk presented by a particular device depends substantially on its intended use .
The GHTF guidance documents Essential Principles of Safety and Performance of Medical Devices and for Labelling for Medical Devices apply to all devices whatever their risk class.
Regulatory controls should be proportional to the level of risk associated with a medical device. The level of regulatory control should increase with increasing degree of risk, taking account of the benefits offered by use of the device. At the same time, the imposition of regulatory controls should not place an unnecessary burden on regulators or manufacturers.
The Classification of an IVD Medical Device is based on the following criteria:
the intended use and indications for use as specified by the manufacturer (specific disorder, condition or risk factor for which the test is intended)
the technical/scientific/medical expertise of the intended user (lay person or professional)
the importance of the information to the diagnosis (sole determinant or one of several), taking into consideration the natural history of the disease or disorder including presenting signs and symptoms which may guide a physician
the impact of the result (true or false) to the individual and/or to public health
Certain jurisdictions may lower the classification of IVD Medical Devices for which traceability is established through the use of reference measurement procedures and/or available reference materials. .
Regulatory Authorities should work towards the establishment of a global classification system specific to in IVD Medical Devices.
Such a system should be based upon common features of existing national requirements with the aim of future convergence.
This system should consist of four risk classes. Based on experience of GHTF Founding Members, this is sufficient to accommodate all IVD Medical Devices and allows an efficient and defined conformity assessment system.
The determination of classification for an IVD Medical Device should be based on a set of rules derived from those features that create risk.
The set of rules should be sufficiently clear that manufacturers may readily identify the class of their IVD Medical Devices, subject, when appropriate, to confirmation by the Regulatory Authority of compliance to the relevant rule.
The manufacturer should document its justification for placing its product into a particular risk class, including the resolution of any matters of interpretation where it has asked a Conformity Assessment Body and/or Regulatory Authority for a ruling.
The rules should be capable of accommodating future technological developments.
Decisions on final classifications, which deviate from the initial rules-based classification, should be weighed against the disadvantages of disharmonized international classification
Where more than one of the classification rules applies to the IVD Medical Device, it should be allocated to the highest class indicated.
Accessories should be classified separately using this guidance document.
Calibrators and control materials with quantitative or qualitative assigned values intended to be used with an IVD reagent should be treated in the same class as the IVD reagent.
While most software is incorporated into the IVD Medical Device itself, some is not. Provided such standalone software falls within the scope of the definition for an ‘IVD Medical Device’, it should be classified as follows:
Where it controls or influences the intended output of a separate IVD Medical Device, it will have the same class as the device itself.
Where it is independent of any other medical device, it is classified in its own right using the rules in Section 8.0 of this document.
Note 1: Performance of software or instrument that is specifically required to perform a particular test will be assessed at the same time as the test kit.
Note 2: The interdependence of the instrument and test methodology prevents the instrument from being assessed separately, even though the instrument itself is still classified as Class A.
Study Group 1 of GHTF continues to support and encourage regulatory harmonization, it recognises that some Regulatory Authorities may have to reflect different local needs when they introduce new regulations on classification. Study Group 1 hopes any such differences will disappear in the course of time.
7.0 Proposed General Classification System for IVD Medical Devices
A four class system is proposed, the use of an alphabetical system in this document is chosen as a distinctive format for GHTF.
Figure 1 indicates the four risk classes of devices. The examples given are for illustration only and the manufacturer must apply the classification rules to each IVD Medical Device according to its intended use.
Figure 1: Proposed general classification system for IVD Medical Devices
Low Individual Risk and Low Public Health Risk
Clinical Chemistry Analyser , prepared selective culture media
Moderate Individual Risk and/or Low Public Health Risk
Vitamin B12, Pregnancy self testing,
Anti-Nuclear Antibody, Urine test strips
High Individual Risk and/or Moderate Public Health Risk
Blood glucose self testing, HLA typing,
PSA screening, Rubella
High Individual Risk and High Public Health Risk
HIV Blood donor screening, HIV Blood diagnostic
Figure 2 shows a conceptual illustration of increasing levels of regulatory requirements as the device risk class increases. These may include, for example:
operation of a quality system (recommended for all devices);
documentation of clinical evidence to support the manufacturer’s specified intended use ;
product testing using in-house or independent resources;
the need for and frequency of independent external audit of the manufacturer’s quality system; and
independent external review of the manufacturer’s technical data.
The concept is expanded in the GHTF guidance document entitled Principles of Conformity Assessment for IVD Medical Devices.
Figure 2: Conceptual illustration of regulatory requirements increasing with device risk class
8.0 The Determination of Device Class
The manufacturer should:
Decide if the product concerned is an IVD Medical Device based on the intended use and the indications for use using the definition in section 4 of this document.
Take into consideration all the rules as listed in section 8 in order to establish the proper classification for the device. Where an IVD Medical Device has multiple intended uses as specified by the manufacturer, which places the device into more than one class, it will be classified in the higher class.
Determine that the device is not subject to special national rules that apply within a particular jurisdiction.
NOTE: Where special national rules are applied, resulting in a device class other than that suggested by the present rules, then a different conformity assessment procedure may be indicated. This may have an effect on the acceptability of such devices for free movement in a global context unless other, or additional, conformity assessment procedures are carried out. For example, where such special national rules result in the lower classification of a particular IVD Medical Device than that indicated in the rules indicated below, and as a consequence, a less vigorous conformity assessment procedure is carried out, this may be unacceptable to other jurisdictions.
9.0 Classification Rules
Rule 1: IVD Medical Devices intended for the following purposes are classified as Class D:
Devices intended to be used to detect the presence of, or exposure to, a transmissible agent in blood, blood components, blood derivatives, cells, tissues or organs in order to assess their suitability for transfusion or transplantation, or
Devices intended to be used to detect the presence of, or exposure to, a transmissible agent that causes a life-threatening often incurable disease with a high risk of propagation
Rationale: Devices in this Class are intended to be used to ensure the safety of blood and blood components for transfusion and/or cells, tissues and organs for transplantation. In most cases, the result of the test is the major determinant as to whether the donation/product will be used. Serious diseases are those that result in death or long-term disability, that are often incurable or require major therapeutic interventions and where an accurate diagnosis is vital to mitigate the public health impact of the condition.
Examples: Tests to detect infection by HIV, HCV, HBV, HTLV. Pyrogenicity tests (Endotoxin Activity Assay) marketed for detection of bacterial contamination of blood components. This Rule applies to all types of assays, such as first-line assays, confirmatory assays and supplemental assays.
Rule 2: IVD Medical Devices intended to be used for blood grouping , or tissue typing to ensure the immunological compatibility of blood, blood components, cells, tissue or organs that are intended for transfusion or transplantation, are classified as Class C, except for ABO, rhesus (C,c,D,E, e) and anti-Kell determination which are classified as Class D.
Rationale: A high individual risk, where an erroneous result would put the patient in an imminent life-threatening situation. The rule divides blood grouping into two subsets depending on the nature of the blood group antigen the IVD Medical Device is designed to detect, and its importance in a transfusion setting.
Examples: HLA, Anti-Duffy, Anti-Kidd
Rule 3: IVD Medical Devices are classified as Class C if they are intended for use:
in detecting the presence of, or exposure to, a serious sexually transmitted agent. Examples: Sexually transmitted diseases, such as Chlamydia trachomatis, Neisseria gonorrhoeae.
in detecting the presence in cerebrospinal fluid or blood of an infectious agent with a risk of limited propagation. Examples: Neisseria meningitidis or Cryptococcus neoformans.
in detecting the presence of an infectious agent where there is a significant risk that an erroneous result would cause death or severe disability to the individual or fetus being tested. Examples: CMV, Chlamydia pneumoniae.
in screening pre-natal women in order to determine their immune status towards transmissible agents. Examples: Rubella or Toxoplasma gondii.
in determining infective disease status or immune status, and where there is a risk that an erroneous result will lead to a patient management decision resulting in an imminent life-threatening situation for the patient. Example: Legionella pneumophila.
in screening for selection of patients for selective therapy, or in the diagnosis of, cancer,
NOTE: those IVD Medical Devices where the therapy decision would usually be made only after further investigation and those used for monitoring and cancer staging would fall into class B under rule 6.
in predictive genetic screening, when the outcome of the test would ordinarily result in a substantial impact on the life of the individual. Examples: Guthrie test for phenylketonuria, Huntington’s Disease, Cystic Fibrosis.
to monitor levels of medicines, substances or biological components, when there is a risk that an erroneous result will lead to a patient management decision resulting in an immediate life-threatening situation for the patient. Example: Cardiac markers, Cyclosporin, Prothrombin time testing .
In the management of patients suffering from a life-threatening infectious disease. Example : HIV Viral Load
Rationale: Devices in this Class present a moderate public health risk, or a high individual risk, where an erroneous result would put the patient in an imminent life-threatening situation, or would have a major negative impact on outcome. The devices provide the critical, or sole, determinant for the correct diagnosis. They may also present a high individual risk because of the stress and anxiety resulting from the information and the nature of the possible follow-up measures.
Rule 4: IVD Medical Devices intended for near-patient testing and self-testing are classified as Class C, except those devices from which the result is not determining a medically critical status, or is preliminary and requires follow-up with the appropriate laboratory test in which case they are Class B.
Rationale: In general, these devices are used by individuals with no technical expertise and thus the labelling and instructions for use are critical to the proper outcome of the test.
Examples for class C: Blood glucose monitoring, near-patient test for Streptococcus B, occult blood test, near-patient devices for blood gases.
Examples for class B: Pregnancy self test, Fertility testing, Urine test-strips.
Rule 5: The following IVD Medical Devices are classified as Class A:
Reagents which possess specific characteristics, intended by the manufacturer to make them suitable for in vitro diagnostic procedures related to a specific examination.
Instruments intended by the manufacturer specifically to be used for in vitro diagnostic procedures
Note : Any product for general laboratory use not manufactured, sold or represented for use in specified in vitro diagnostic applications are not deemed to be IVD Medical Devices . However, in certain jurisdictions products for general laboratory use are considered to be IVD Medical Devices.
Rationale: These devices present a low individual risk and no or minimal public health risk.
Examples: Selective/differential microbiological media, identification kits for cultured microorganisms, wash solutions, instruments and plain urine cup.
Note 1: In certain jurisdictions there might be differences to whether a device classified in this rule is considered an IVD Medical Device.
Note 2: Performance of software or instrument that is specifically required to perform a particular test will be assessed at the same time as the test kit.
Note 3: The interdependence of the instrument and test methodology prevents the instrument from being assessed separately, even though the instrument itself is still classified as Class A.
Rule 6: IVD Medical Devices not covered in Rules 1 through 5 are classified as Class B.
Rationale: These devices present a moderate individual risk as they are not likely to lead to an erroneous result that would cause death or severe disability, have a major negative impact on the outcome or put the individual in immediate danger. The devices are usually one of several determinants. If it is the sole determinant however other information is available, such as presenting signs and symptoms or other clinical information which may guide a physician, the risk classification may be justified. Other appropriate controls may also be in place to validate the results. This Class also includes those devices that present a low public health risk because they detect infectious agents that are not easily propagated in a population.
Examples: Blood gases, H. pylori and physiological markers such as hormones, vitamins, enzymes, metabolic markers.