QIBA Concepts

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  • QIBA is an initiative sponsored by RSNA to advance quantitative imaging and the use of imaging biomarkers in clinical trials and clinical practice by engaging researchers, healthcare professionals and industry.


  • A Profile is an implementation guide. A Profile identifies a biomarker and a level of technical performance, and then defines what each person or device involved in generating that biomarker must do to achieve that level of technical conformance.


  • Groundwork are investigation projects coordinated by QIBA to do things like understand sources of variance, quantify current performance, or validate underlying assumptions and details of Profiles.


  • Actors are the people (such as radiologists or technologists) and devices (such as scanners or analysis software) for which a Profile specifies requirements (e.g. The technologist shall record the current patient weight at the time of each scan).


  • Activities represent steps in the chain of preparing for and generating biomarker values (e.g. product validation, system calibration, patient preparation, image acquisition, image analysis, etc.). Activities are a convenience to organize committee analysis of factors affecting biomarker performance and to subdivide the profile requirements by step.


  • A Claim is a statement of the technical performance of a biomarker that is expected if all the Actors generating the biomarker conform to the specifications in the Profile.


  • Conformance to a Profile involves each Actor conforming to all the requirements placed on it in the Profile.

Assessment Procedures

  • Conformance to most requirements can be assessed by direct observation. Some requirements (often performance metrics) depend on being assessed using a particular Assessment Procedure. The assessment procedure defines how a metric is measured. The original requirement defines what value constitutes a pass/fail for the metric.


  • A Checklist contains the exact same requirements described in the Activities, but groups them by Actor for convenient assessment of Actor conformance.

Conformance Statement

  • A Conformance Statement document is a formal attestation that an Actor conforms to all the requirements as specified by a Profile.


  • QIBA uses the term Conformance rather than Compliance.

Normative Text

  • Also called "shall language". It unambiguously states what Actors shall do to conform.

Informative Text

  • Text that helps understanding but does not change the requirements. Informative text in Profiles might explain the rationale behind a requirement or how it might be met in practice. Informative text is hopefully helpful for some, but a reader can completely ignore all informative text and still successfully implement the profile requirements.

Profile Stages

  • QIBA Profiles progress through a sequence of stages of maturity as they are developed. These Profile Stages represent increasing degrees of confidence and evidence supporting the biomarker performance expressed in the Claim.


  • Validation is the process of assessing a biomarker and its measurement performance characteristics, and determining the range of conditions under which the biomarker will give reproducible and accurate data (ref). QIBA does not assert that biomarkers in its Profiles are validated, however much of the QIBA profiling work, particularly at later stages, might contribute to subsequent validation.


  • Qualification is the evidentiary process of linking a biomarker with biological processes and clinical end points for a specific context of use (ref). QIBA does not qualify biomarkers. It is hoped that QIBA Profiles provide a good detailed guide for clear consistent implementation of a biomarker, that the QIBA Profile Claim (particularly after confirmed) contributes clear performance characteristics, that the QIBA Groundwork findings and data may be useful to the qualification process, and that the biomarkers selected for QIBA Profiles would be good candidates for qualification.