Informed consent and communication of risk from radiological and nuclear medicine examinations: how to escape from a communication inferno
http://www.100md.com
《英国医生杂志》
1 Institute of Clinical Physiology, National Research Council, Via Moruzzi, 1 56 100, Pisa, Italy picano@ifc.cnr.it
Radiological and nuclear medicine examinations confer a definite (albeit low) long term risk of cancer, but patients undergoing such examinations often receive no or inaccurate information about these risks. Picano argues that this disregard of patient autonomy is no longer acceptable and suggests a practicable way of communicating risk
Introduction
The language of radiation protection is not readily understood by non-specialists, and it is easy to get lost in a lexicon that expresses radiation doses in megabecquerels, millicuries, millirems, milliamperes, microsieverts, and "source-related dose constraints," and risks as nominal probability coefficients for stochastic effects. The hapless prescribing (and practising) physician who wants to know about radiation risk enters a Tower of Babel, where essential information is "hidden beneath the veil of verses so obscure."
As the best selling author Michael Crichton wrote when he was a young graduate from Harvard Medical School, "Medical writing is a highly skilled, calculated attempt to confuse the reader."12 Unfortunately, a side effect of this confusion is that physicians become disoriented and eventually ignore the risks of what they are doing. The real issue is not that physicians do not communicate risks to patients, but rather that physicians do not communicate with other physicians, not even with themselves. They do not communicate radiological risks for the good reason that they are ignorant of risks.13 This may help to explain why 30% of tests involving ionising radiation are inappropriate—that is, patients take a long term risk without a commensurate acute benefit.5
How to wake up from this communication nightmare? One suggestion is that doctors should communicate risk through equivalents of ordinary life activities such as driving a car on the highway or smoking cigarettes.14 For example, a chest computed tomogram corresponds to about 400 chest x rays, implying a risk similar to that of having a car crash during 4000 km of highway driving or of smoking 700 cigarettes. Here, we have a paradox: in Europe, when you buy a cigarette pack you are faced with a large, bold, and funereal black notice stating that "Smoking severely damages your health" or "You can die from smoking"; then you have a thallium scan, and no one minds telling you that the risk corresponds to smoking 1400 cigarettes.14
Expressing a radiological dose as multiples of a chest x ray might be an even simpler means of communicating risk. This method has been suggested by the UK college of radiologists and has been endorsed in the European Commission's guidelines on imaging.15 The "dose unit" is familiar to both doctors and to patients, and it helps to express, in a straightforward fashion, the concept that the higher the radiation dose, the higher the long term risk of cancer.
A graphical presentation of radiological risk
Medical professionalism in the new millennium: a physician charter. JAMA 2002;136: 243-6.
European Parliament. The charter of fundamental rights of the European Union. www.europarl.eu.int/charter/default_en.htm (accessed 21 May 2004).
World Medical Association. Declaration of Helsinki. www.wma.net/e/policy/b3.htm (accessed 21 May 2004).
Meara J. Getting the message across: is communicating risk to the public worth it? J Radiol Prot 2002;22: 79-85.
Hall EJ. Lessons we have learned from our children: cancer risks from diagnostic radiology. Pediatr Radiol 2002;32: 700-6.
Overbeek FJ, Pauwels EK, Bloem JL, Camps JA, Geleijns J, Broerse JJ. Somatic effects in nuclear medicine and radiology. Appl Radiat Isot 1999;50: 63-72.
Lawton MP. Legal aspects of iatrogenic disorders: discussion paper. J R Soc Med 1983;76: 289-91.
Lewars M. Sustainability of medical imaging. To obtain informed consent from everyone is impossible . BMJ 2004;328: 1201.
SFBMN. Societé Fran?aise de Biophysique et Médecine Nucléaire. Informations du public. www.sfbmn.org/pub/index.htm (accessed 4 Sep 2004).
United Nations Scientific Committee on the Sources and Effects of Ionising Radiation. Report on the effects of atomic radiation to the General Assembly, 2000. Medical radiation exposures. New York, NY: United Nations, 2001.
Office for Protection from Research Risks, Department of Health and Human Services. Code of federal regulations. Title 45: public welfare. Part 46—protection of human subjects. Bethesda, MD: National Institutes of Health, 1991. www.hhs.gov/ohrp/humansubjects/guidance/45cfr46.htm (accessed 30 Sep 2004).
Crichton M. Sounding board: Medical obfuscation: structure and function. N Engl J Med 1975;293: 1257-9.
Shiralkar S, Rennie A, Snow M, Galland RB, Lewis MH, Gower-Thomas K. Doctors' knowledge of radiation exposure: questionnaire study. BMJ 2003;327: 371-2.
Zamenhof R. Risk list. JPNM Physics, 1997. www.med.harvard.edu/JPNM/physics/safety/risks/risklist.html (accessed 1 Sep 2004).
European Commission. Radiation protection 118: referral guidelines for imaging. Luxembourg: Office for Official Publications of the European Communities, 2001. http://europa.eu.int/comm/environment/radprot/118/rp-118-en.pdf (acessed 30 Sep 2004).
International Commission on Radiological Protection. Radiation and your patient: a guide for medical practitioners. 2001. www.icrp.org/docs/Rad_for_GP_for_web.pdf (accessed 4 Sep 2004).
Gofman JW. Radiation-induced cancer from low-dose exposure: an independent analysis. San Francisco, CA: Committee for Nuclear Responsibility, 1990.
Berrington de Gonzalez A, Darby S. Risk of cancer from diagnostic x-rays: estimates for the UK and 14 other countries. Lancet 2004;363: 345-51.
Picano E. Risk of cancer from diagnostic x-rays . Lancet 2004;363: 1909-10.
Picano E. Sustainability of medical imaging. BMJ 2004;328: 578-80.(Eugenio Picano, clinical )
Radiological and nuclear medicine examinations confer a definite (albeit low) long term risk of cancer, but patients undergoing such examinations often receive no or inaccurate information about these risks. Picano argues that this disregard of patient autonomy is no longer acceptable and suggests a practicable way of communicating risk
Introduction
The language of radiation protection is not readily understood by non-specialists, and it is easy to get lost in a lexicon that expresses radiation doses in megabecquerels, millicuries, millirems, milliamperes, microsieverts, and "source-related dose constraints," and risks as nominal probability coefficients for stochastic effects. The hapless prescribing (and practising) physician who wants to know about radiation risk enters a Tower of Babel, where essential information is "hidden beneath the veil of verses so obscure."
As the best selling author Michael Crichton wrote when he was a young graduate from Harvard Medical School, "Medical writing is a highly skilled, calculated attempt to confuse the reader."12 Unfortunately, a side effect of this confusion is that physicians become disoriented and eventually ignore the risks of what they are doing. The real issue is not that physicians do not communicate risks to patients, but rather that physicians do not communicate with other physicians, not even with themselves. They do not communicate radiological risks for the good reason that they are ignorant of risks.13 This may help to explain why 30% of tests involving ionising radiation are inappropriate—that is, patients take a long term risk without a commensurate acute benefit.5
How to wake up from this communication nightmare? One suggestion is that doctors should communicate risk through equivalents of ordinary life activities such as driving a car on the highway or smoking cigarettes.14 For example, a chest computed tomogram corresponds to about 400 chest x rays, implying a risk similar to that of having a car crash during 4000 km of highway driving or of smoking 700 cigarettes. Here, we have a paradox: in Europe, when you buy a cigarette pack you are faced with a large, bold, and funereal black notice stating that "Smoking severely damages your health" or "You can die from smoking"; then you have a thallium scan, and no one minds telling you that the risk corresponds to smoking 1400 cigarettes.14
Expressing a radiological dose as multiples of a chest x ray might be an even simpler means of communicating risk. This method has been suggested by the UK college of radiologists and has been endorsed in the European Commission's guidelines on imaging.15 The "dose unit" is familiar to both doctors and to patients, and it helps to express, in a straightforward fashion, the concept that the higher the radiation dose, the higher the long term risk of cancer.
A graphical presentation of radiological risk
Medical professionalism in the new millennium: a physician charter. JAMA 2002;136: 243-6.
European Parliament. The charter of fundamental rights of the European Union. www.europarl.eu.int/charter/default_en.htm (accessed 21 May 2004).
World Medical Association. Declaration of Helsinki. www.wma.net/e/policy/b3.htm (accessed 21 May 2004).
Meara J. Getting the message across: is communicating risk to the public worth it? J Radiol Prot 2002;22: 79-85.
Hall EJ. Lessons we have learned from our children: cancer risks from diagnostic radiology. Pediatr Radiol 2002;32: 700-6.
Overbeek FJ, Pauwels EK, Bloem JL, Camps JA, Geleijns J, Broerse JJ. Somatic effects in nuclear medicine and radiology. Appl Radiat Isot 1999;50: 63-72.
Lawton MP. Legal aspects of iatrogenic disorders: discussion paper. J R Soc Med 1983;76: 289-91.
Lewars M. Sustainability of medical imaging. To obtain informed consent from everyone is impossible . BMJ 2004;328: 1201.
SFBMN. Societé Fran?aise de Biophysique et Médecine Nucléaire. Informations du public. www.sfbmn.org/pub/index.htm (accessed 4 Sep 2004).
United Nations Scientific Committee on the Sources and Effects of Ionising Radiation. Report on the effects of atomic radiation to the General Assembly, 2000. Medical radiation exposures. New York, NY: United Nations, 2001.
Office for Protection from Research Risks, Department of Health and Human Services. Code of federal regulations. Title 45: public welfare. Part 46—protection of human subjects. Bethesda, MD: National Institutes of Health, 1991. www.hhs.gov/ohrp/humansubjects/guidance/45cfr46.htm (accessed 30 Sep 2004).
Crichton M. Sounding board: Medical obfuscation: structure and function. N Engl J Med 1975;293: 1257-9.
Shiralkar S, Rennie A, Snow M, Galland RB, Lewis MH, Gower-Thomas K. Doctors' knowledge of radiation exposure: questionnaire study. BMJ 2003;327: 371-2.
Zamenhof R. Risk list. JPNM Physics, 1997. www.med.harvard.edu/JPNM/physics/safety/risks/risklist.html (accessed 1 Sep 2004).
European Commission. Radiation protection 118: referral guidelines for imaging. Luxembourg: Office for Official Publications of the European Communities, 2001. http://europa.eu.int/comm/environment/radprot/118/rp-118-en.pdf (acessed 30 Sep 2004).
International Commission on Radiological Protection. Radiation and your patient: a guide for medical practitioners. 2001. www.icrp.org/docs/Rad_for_GP_for_web.pdf (accessed 4 Sep 2004).
Gofman JW. Radiation-induced cancer from low-dose exposure: an independent analysis. San Francisco, CA: Committee for Nuclear Responsibility, 1990.
Berrington de Gonzalez A, Darby S. Risk of cancer from diagnostic x-rays: estimates for the UK and 14 other countries. Lancet 2004;363: 345-51.
Picano E. Risk of cancer from diagnostic x-rays . Lancet 2004;363: 1909-10.
Picano E. Sustainability of medical imaging. BMJ 2004;328: 578-80.(Eugenio Picano, clinical )