2011 • Volume 3, Number 3
In this issue:
What Exactly are QIBA Profiles and Why are They
By ANDREW J. BUCKLER,
ANALYSIS TOOLS AND
Informatics and Database Infrastructure for Proficiency Testing of Quantitative
By ALDEN DIMA,
RSNA 2011: QIBA Meetings and
QI / IMAGING
BIOMARKERS IN THE LITERATURE
Search on QIBA Profiles and Why They are Important
IN MY OPINION
What Exactly are QIBA
Profiles and Why are They Important?
By ANDREW J. BUCKLER, MS
Enhanced imaging techniques
have made medical imaging an essential component of healthcare. An increasing
number of quantitative analysis approaches ranging from morphological to
functional measurements have been developed to create objective and quantitative
readouts. Quantitative imaging has the potential to improve the value of
diagnostic testing and enhance clinical productivity.
While the imaging industry
is transitioning to developing devices that are optimized for quantitative
imaging, performance expectationsâ€”particularly the rigor with
which performance is statistically characterizedâ€”are higher
with quantitative than with qualitative imaging. Moreover, a standardized
interpretation of the results is necessary in order that the measurements be
understood as clinically significant. Individual companies are constrained by
their business models to pursue only activities that can be justified in the
short-term with respect to that company. Furthermore, individual manufacturers do
not commonly address the need for cross-vendor standardization.
Profile is a document that describes how to achieve a specific performance claim
when targets (inanimate or living) are imaged under specific conditions
(including, but not limited to, imaging system requirements and protocols). It
organizes and records relevant information from the published literature as well
as results of the collaborative work by QIBA participants.
A Profile consists of one or
more "Claims" and associated "Details."
- Claims tell a user what
can be accomplished by following the Profile
- Details tell a vendor
what must be implemented in their product before they can declare compliance
with the Profile, and tell a user the necessary procedures for achieving the
As such, a Profile serves as
both a documented standard as well as a basis for the cooperation of stakeholders
in assessing performance.
With such standardization in
place, it would be possible to perform multiple studies and pursue objectives
that would not be feasible for individual sponsors alone, be they
biopharmaceutical companies seeking to develop drugs or hardware/software
companies seeking to develop solutions for clinical care. Although many
stakeholders are interested in this goal, none can accomplish it alone. The goal
of QIBA is to establish processes and Profiles (standards documents) that will
lead to acceptance of quantitative imaging applications by the imaging
In the end, more consistency
can be expected in image interpretation, which should create more efficient
multicenter clinical trials and be useful as patients move among providers. It
will be increasingly possible for physicians to rely on consistent quantitative
interpretations as the standard of care. In theory, medical workflows
incorporating these stable measures should compare favorably to workflows without
them, in terms of improved patient outcomes and lower costs of care. Without this
effort, variations in measures diminish the value of imaging metrics and restrict
profiles are available for public comment. Please visit the QIBA WIKI at qibawiki.rsna.org/index.php?title=Work_Product_for_Review
*QIBA = Quantitative Imaging Biomarkers Alliance
Andrew J. Buckler, MS,
has over 25 years of experience in the device manufacturing industry. Mr. Buckler
serves as Program Director of QIBA, scientific advisor to the Foundation for the
National Institutes of Health (FNIH) in connection with the qualification of
volumetric CT and quantitative FDG-PET for regulatory decision making in clinical
trials, and as a PI for QI-Bench, a National institute of Standards and
Technology (NIST)-supported program to develop informatics services used to
assess performance of quantitative imaging biomarkers.
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ANALYSIS TOOLS & TECHNIQUES
Informatics and Database Infrastructure for Proficiency Testing of Quantitative
By ALDEN DIMA, MS
Imaging biomarkers are
intended for use in both patient care and in clinical trials of new therapies.
Although both qualitative and quantitative biomarkers are useful, the need for
quantitative biomarkers is currently emphasized by the medical community.
Quantitative imaging should allow for precise measurement of clinically relevant
features when applied and interpreted in a consistent manner. However, the use of
imaging biomarkers is hindered by a lack of a standardized interpretation. This
in turn, is exacerbated by large measurement variabilities under differing use
contexts, imaging modalities and platforms.
The purpose of the QI-Bench
project is to collect evidence
supporting the implementation of imaging biomarkers and to ensure that
sufficient, quality data are generated to enable the responsible use of these new
tools in clinical settings. The project proposes an overall architecture based on
open-source software in which needed functionality is divided among five
applications: Specify, Formulate, Execute, Analyze, and Package.
- Specify will allow users to specify context for use and
assay methods using consensus terms. It will be a
Editor application that builds the internal representation to specify
quantitative imaging biomarkers and assay methods used downstream.
- Formulate will allow for the assembly of applicable
reference data sets that include both imaging and non-imaging clinical data. It
will form a Linked Data Archive with an extension to clinical data and is the
part of the project that is most closely associated with existing caBIG
tools, comprising such
capabilities as caB2B, caIntegrator, the PODS data elements, and an NBIA
connector into Kitware's MIDAS image archiving system.
- Execute will enable the composition and iteration of
batch analyses on reference data and accumulation of quantitative readouts for
analysis. It serves as a Reference Data Set Manager and a Batch Analysis
Service and results in annotation and image mark-up across large data sets. The
Execute application will be implemented using Kitware's MIDAS and
BatchMake software, as well
as the Condor grid.
- Analyze will characterize a biomarker method relative to
its intended use by applying existing analysis tools and allowing those tools
to be extended as needed. Analyze is most closely associated with the
Measurement Variability Toolkit portion of the Algorithm Validation
Toolkit as well as the ideas
being discussed for a library of reference statistical analysis methods.
- Package will allow users to compile evidence for
regulatory filings and enable a standards-based transfer to regulatory
agencies. This portion of the project is most closely associated with the
Clinical Data Interchange Standards Consortium (CDISC) and the U.S. Food and
Drug Administration (FDA) and would generate data in the study data tabulation
model (SDTM) for biomarker qualification in CDER and test approval/clearance in
CDRH, as well as
corresponding worldwide agencies.
These applications would be
available in two forms: as web services linking to the databases on the project
server dev.bbmsc.com; and as a local
installation for more sophisticated users.
Our approach is to run two
parallel core activities. The first starts with use case analysis and proceeds to
requirements and systems engineering; the other creates demonstrators that extend
existing system capabilities. A shared activity is an inventory of current system
capabilities and a gap analysis. In the fall of 2011, we will initiate an
iterative development process to create the services. We will report our progress
via semi-annual reports that will be available in February and August.
 QI-Bench, www.qi-bench.org/wiki
QI-Bench "Specify" Scope Description, June 2011, Rev 0.1,
ProtÃ©gÃ© Ontology Editor and Knowledge Acquisition System,
Welcome to NCBO BioPortal, bioportal.bioontology.org
on Rails, rubyonrails.org
QI-Bench "Formulate" Scope Description, June 2011, Rev 0.1,
Cancer Biomedical Informatics Grid (caBIG), cabig.nci.nih.gov
QI-Bench "Execute" Scope Description, June 2011, Rev 0.1,
Condor: High Throughput Computing, www.cs.wisc.edu/condor
QI-Bench "Analyze" Scope Description, June 2011, Rev 0.1,
Algorithm Validation Toolkit, cabig.nci.nih.gov/tools/AVT
QI-Bench "Package" Scope Description, June 2011, Rev 0.1,
Medical Devices, www.fda.gov/MedicalDevices/default.htm
Alden Dima, MS, is a Computer Scientist in the Software and Systems Division
(SSD) of the National Institute of Standards and Technology (NIST) and is the
project lead for Medical Imaging within NIST/SSD.
RSNA 2011: QIBA
Meetings and Activities
YOUR CALENDAR: RSNA 2011
Quantitative Imaging/Imaging Biomarkers
Special Interest Session
â€¢ Monday, November 28, 4:30
QIBA Technical Committees Working
â€¢ Wednesday, November 30,
THE LAKESIDE LEARNING CENTER (HALL E)
The Quantitative Imaging Reading
RSNA 2011 will once again feature The
Quantitative Imaging Reading Room. This educational showcase will provide
visual and experiential exposure to quantitative imaging and biomarkers through
exhibitor products that integrate quantitative analysis into the image
interpretation process. Participants can learn through hands-on exhibits
featuring informational posters, computer-based demonstrations and Meet the
Expert presentations scheduled throughout the week.
The ongoing work of the Technical Committees is posted on the QIBA wiki page:
http:/qibawiki.rsna.org/. New participants
in QIBA Technical Committees are always welcome; please contact QIBA@rsna.org for more information.
QI/IMAGING BIOMARKERS IN THE
PubMed Search on: "What
Exactly are QIBA Profiles and Why are They Important?"
Each issue of QIBA Quarterly features a link to a dynamic search in
PubMed, the National Library of Medicine's interface to its MEDLINE database.
Link to articles on: "What Exactly are QIBA Profiles and Why are They Important?"
For more information, please visit
the QIBA WIKI:
are Profiles and Protocols?