Effect of “collaborative requesting” on consent rate for organ donation: randomised controlled trial (ACRE trial)BMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b3911 (Published 08 October 2009) Cite this as: BMJ 2009;339:b3911
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I congratulate the ACRE Collaborators (BMJ 17 October 2009;339: 902 –
899) for having randomized patients meeting the criteria for brain stem
death between ‘routine request to relatives’ versus ‘collaborative
requesting’ to determine if, and by how much, relatives’ consent rate was
increased by collaborative requesting.
Plausible prior assumptions are key in designing any randomized
controlled trial. There is robust evidence in the UK that a) relatives’
consent rate in the 21st century is around 60% 1 2, b) relatives’ consent
rate was 70% in 1989-90 3 4 , and c) that even sustained positive
publicity about transplantation achieved only a one quarter reduction in
relatives’ refusal rate 4. Thus, the ACRE trial should have been designed
to detect, at best, an increase in consent rate from 60% to 70%
(equivalent to odds ratio on consent by ‘collaborative requesting’ of 1.56
= 70/30 * 40/60) which required the randomization of over 700 patients
meeting the criteria for brain stem death. Instead, its group sequential
design was based on 60% versus over-optimistic target of 75% consent rate.
The ACRE triallists’ eventual 95% confidence interval for the odds
ratio on consent by ‘collaborative requesting’ was 0.80 (95% CI: 0.43 to
1.53), which clearly excludes an odds ratio of 1.56; but does not exclude
a more modest improvement in consent rate (such as from 60% to 67%, odds
ratio of 67/33 * 40/60 = 1.33) in respect of which randomization of some
1,500 patients meeting the criteria for brain stem death would have been
required ab initio, 10 times more than in ACRE’s per protocol analysis on
The ACRE trial should send a clear quantitative signal against over-
optimism about how readily reducible is the relatives’ refusal rate of 40%
that has been characteristic of the opt-in era to the National Organ Donor
Register. Names currently on the National Organ Donor Register, fewer than
20 millions, fall far short of public willingness in extremis which, even
now, is 60%.
Success is measured by increased numbers of donated organ, not by
increase in names on the National Organ Donor Register. The latter have
increased but relatives’ refusal rate has remained intransigent. The
message therein is loud for those that have ears to hear, as both Chief
Medical Officer and Prime Minister have.
Change to presumed-consent for organ donation (unless the deceased
has registered an opt-out) needs now to be revisited; and from a more
strongly-quantitative perspective than Organ Donation Taskforce achieved 5
6 7. [409 words]
Sheila M. Bird, MRC Biostatistics Unit, CAMBRIDGE CB2 0SR
Competing interest: I designed and analysed the1989-90 confidential
audit of all deaths in intensive care units.
The Corresponding Author has the right to grant, and does grant, an
exclusive licence (or non exclusive for government employees) on a
worldwide basis to the BMJ Publishing Group Ltd and its Licensees to
permit this article (if accepted) to be published in BMJ editions and any
other BMJPGL products and sublicences to exploit all subsidiary rights, as
set out in our licence (http://resources.bmj.com/bmj/authors/checklists-
1. Barber K, Falvey S, Hamilton C, Collett D, Rudge C. Potential for
organ donation in the United Kingdom: audit of intensive care records.
British Medical Journal Online First doi: 10.1136/bmj.38804.658183.55
(published 26 April 2006).
2. Murphy C, Counter C. Potential donor audit. Summary report for the
24 month period 1st April 2007-31st March 2009: UK Blood and Transplant
-2009.pdf. Accessed 18 October 2009).
3. Gore SM, Hinds CJ, Rutherford AJ. Organ donation from intensive
care units in England. British Medical Journal 1989; 299: 1193 – 1197.
4. Gore SM, Cable DJ, Holland AJ. Organ donation from intensive care
units in England and Wales: two year confidential audit of deaths in
intensive care. British Medical Journal 1992; 304: 349 – 355.
5. The Organ Donor Taskforce (chair: Elizabeth Buggins). The
Potential Impact of an Opt Out System for Organ Donation in the UK.
Department of Health, London: 17 November 2008.
re -accessed on 18 October 2009)
6. Rithalia A, McDaid C, Suekarran S, Myers L, Sowden A. Impact of
presumed consent for organ donation on donation rates: a systematic
review. British Medical journal 2009; 338: a3162.
accessed 21 July 2009).
7. English V, Sheather J, Sommerville A, Chrispin E. Ethics
briefings: Taskforce rejects presumed consent for organ donation. Journal
of Medical Ethics 2009; 35: 335 – 336.
I designed and analysed confidential audit of all deaths in intensive care units in 1989-90
Competing interests: No competing interests
Ethics of „collaborating requesting“ and the „presumptive approach“ in the organ donation process should be considered
In their randomised controlled trial, the ACRE Trial Collaborators
compared the consent rates for organ donation when using collaborative
requesting versus routine requesting by the patient’s clinician.(1)
Because no clear consensus about the definition of this alternative
strategy exists, the authors reduced it to a common demoninator, i.e. that
the patient’s clinician and a donor transplant coordinator both took part
in the interview with the relatives. The statistical analysis did not show
any increase in the consent rates when the alternative requesting was
used. The authors discussed the absent effect as a result of unstructured
training for donor transplant coordinators and raised the question, if a
structured training would make the collaborative requesting more
effective. They cited a recent BMJ editorial by Teresa Shafer about the
Organ Donation Breakthrough Collaborative of the US Department of Health
Human Services to give an example for such a structured training.(2)
At that point, conflicting ethical obligations appear: The phrase
“structured training” masks to some extent the real nature of the strategy
recommended by Teresa Shafer, that “successful requestors act as advocates
for people of the organ transplant waiting list” and “are presumptive, not
neutral”. The so called “presumptive approach”(3) is far from widley
accepted like the ACRE Trial Collaborators described the collaborative
requesting to be. In the New England Journal of Medicine, Robert Truog
discussed the presumptive approach as undermining the ethics of informed
consent, which is regarded as an axiom of clinical research.(4)
Organ donation and transplanting do save lives, but we have to
consider the ethics of different strategies to fill the gap between the
number of organs needed and the number of organs donated. Donor transplant
coordinators should not be in the role of dual advocay, they should be the
advocates of the relatives making a decision, that has to be based on
informed choice, not uninformed coercion.
1. ACRE Trial Collaborators. Effect of "collaborative requesting" on
consent rate for organ donation: randomised controlled trial (ACRE trial).
2. Shafer TJ. Improving relatives' consent to organ donation. BMJ
3. Zink S, Wertlieb S. A study of the presumptive approach to consent
for organ donation. A new solution for an old problem. Crit Care Nurse
4. Truog RD. Consent for organ donation - balancing conflicting
ethical obligations. N Engl J Med 2008;358:1209-11.
Competing interests: No competing interests