RE: x-rays, IRB, rad-safty, consents, regs

["David Scherer" <scherer@mirlink.wustl.edu>]

Dr. Javire Villanueva-Meyer asked about RSC and IRB review of research
protocols.


One academic health center with which I have been associated required both RSC
and IRB approval for both materials and machine-produced (diagnostic and
therapeutic) radiation.  (This was imposed by the state Health Department.)  As
I recall, there were some problems associated with the double-review process.
Logistics and coordination between the committees was the worst.  First, the
IRB insisted that they be the final review authority.  RSC approval was
required _before_ the IRB would consider the request.  The PI would give the
protocol to the RSO two weeks before the RSC meeting.  This allowed time for
distribution and review by the members before the meeting.  The IRB meeting was
scheduled two weeks after the RSC, but they needed the protocol two weeks
before their meeting, too.  Thus, the RSC would act on a protocol an the day
before the IRB deadline.  If there were any substantive changes, the PI would
miss the IRB deadline and have to wait another month.  This was perceived as a
competitive disadvantage for the clinical research employing radiation and was
a recurring sore point.  I'm not sure how/if the problem has worked out.

IMHO the advisability of such dual review is a mixed bag.  The RSC included
more people expert in radiation risks, but for large multi-center
collaborations the protocols had already been reviewed to death.  Often the
situation was a take-it-or-leave-it choice, since the protocol was dictated by
RTOG, ECOG, or a pharmaceutical company and local changes to the protocol were
not allowed.  I don't recall refusing any protocols or requiring major changes
in the research design, although one protocol calling for doses of .5 - 1 Gy to
neonates did receive substantial comment/oversight.

In the matter of informed consent I continue to believe that the consent
document should be a general one with a balanced view of all the risks. 
Radiation should not be treated differently just because of the administrative
structure regulating it.  The RSC did develop a short, general description of
radaition risk that was incorportated in all diagnostic imaging protocols and
another for oncology.  Occasionally, the statements were modified for unusual
situations. The description should be in plain, nontechnical terms.  When
jargon is used in these documents the "consent" is often not viewed as being
"informed."

My current institution does not require RSC review for machine-produced
radiation, but the informed consent must address radiation risks.

By the way, your comment about the CT doses implied that the dose from several
slices were additive.  If the collimation is less than the table increment (or
pitch for spiral CT), the primary beam doses do not add, but the scatter does. 
You should use the multiple scan average dose (MSAD) to describe the absorbed
dose.

David Scherer
scherer@mirlink.wustl.edu