541
will encourage parents and professionals to observe children carefully as they come to walk. Those skilled in surveillance will be able to assess the clinical picture in children who do walk late and offer developmental guidance or further
referral as appropriate. 1. Neligan G, Prudham D. Norms for four standard developmental milestones by sex, social class and place in family. Dev Med Child Neurol 1969; 11: 413-22. 2. Colver AF, Steiner H. Health surveillance of pre-school children. Br Med
J 1986; 293: 258-60. 3. Chaplais J de Z, MacFarlane JA. A review of four hundred and four late walkers. Arch Dis Child 1984; 59: 512-16. 4. Johnson A, Goddard O, Ashurst H. Is late walking a marker of morbidity? Arch Dis Child 1990; 65: 486-88. 5. Smith RA, Rogers M, Bradley DM, Sibert JR, Harper PS. Screening for Duchenne muscular dystrophy. Arch Dis Child 1989; 64: 1017-21. 6. Standing Medical Advisory Committee and Standing Nursing and
Midwifery Advisory Committee. Screening for detection of congenital dislocation of the hip. London: DHSS, 1986. 7. Robson P. Screening for children. Developmental Health 1978; 98: 231-37.
paediatrics. J R
Soc
TAKING RISKS IN GENERAL PRACTICE It might be thought that a good general practitioner should never take risks, but Grol and colleagues have lately argued that doctors who seek to minimise uncertainty and to avoid risks in primary care are acting irrationally. These researchers compare the reported attitudes to risk-taking of general practitioners in Belgium, Holland, and the UK and suggest that Dutch general practitioners are more willing to take risks in clinical decision making because their vocational training makes them aware of the dangers of defensive medicine. These conclusions are open to the criticisms that reported attitudes do not necessarily reflect clinical practice (the evidence presented to substantiate this link is tenuous) and that the role ascribed to educational methods is speculative. Nevertheless, the paper does raise several important issues. It is potentially misleading to label a decision to "wait and see" after careful clinical assessment as "risk taking", a phrase that suggests carelessness and irresponsibility. General practitioners face the unenviable problem of needing to assess the likelihood of serious disease in a population in which such events are rare. Not only is there a problem of maintaining vigilance but also the diagnostic value of symptoms and signs in general practice is much less than in hospital medicine. A clinical sign with 90% sensitivity and 95 % specificity has a predictive value of 95 % if the underlying prevalence of disease is 50 %, but only 15 % if the prevalence is 1%. In primary care, knowledge of the proportion of patients with a certain symptom who do not have serious disease becomes more important than knowledge of the proportion who do. If general practitioners adopt the same diagnostic and investigative thresholds as do their hospital colleagues they will generate much suffering through false alarms. So, how should general practitioners achieve the correct balance between reassurance and diagnostic intervention? The issue is the appropriate management of low-level risks, a task that has intrigued epidemiologists and environmental scientists for some years and about which there have been many reports 2 The first step in risk management is simple: quantify the risk. This means assessing the significance of symptoms and signs in the community rather than working backwards from descriptions in medical textbooks which are
based on hospital case-series. In the UK introduction of on-desk computers in general practice surgeries has made this assessment possible for the first time, and it is tragic that the Government has not provided adequate support for this development in England and Wales, preferring to leave the task to commercial organisations funded by the
pharmaceutical industry. The Dutch seem to have little doubt that if one can provide better data about disease prevalence and the diagnostic significance of symptoms and signs in the community, general practitioners could be taught to make better clinical decisions. It is certainly true that doctors are ill at ease with uncertainty and Eddy has argued cogently that clinical practice would be much improved if physicians were educated to be more numerate in the sense of "learning the language" of probability.4 Pioneering work at McMaster has shown that probability theory can be used successfully in a clinical context.5 So, although there is no firm evidence that numerate doctors are better doctors at providing immediate clinical care, and the true value of numeracy may lie in planning and evaluating practice protocols for the management of disease rather than in making instant decisions in the surgery, some progress has been made already in translating theory into practice. It is also possible that knowledge-based computer systems, which can generate diagnostic hypotheses and use probabilistic data without exposing probabilistic reasoning to the doctorsmay soon revolutionise clinical practice. The most important element in medical decision making is framing the question-selecting the salient information from the morass.7 To achieve this in general practice, as in hospital medicine, the patient must be listened to and examined carefully. It is clearly an unacceptable risk not to do this. But in taking a decision to act on the information elicited (even if the action is a diagnostic test) the general practitioner must be more aware than hospital colleagues of the danger of false-positive information. The acceptable and necessary "risk" taken is the selection of a higher threshold for action. Despite Grol’s paper, it is not established that British doctors set this threshold higher, and therefore take more risk, than do their Dutch colleagues. A comparative study from general practice 10 years ago provided no evidence for this notion,8 and Payer’s overview of medicine and culture in Europe characterised the British as "doing less of everything".9 However, it is clear that the Dutch are looking ahead and teaching primary care doctors to be numerate in the belief that it will help them to deal better with uncertainty and low-level risk in the future. R, Whitfield M, De Maesener J, Mokkink H. Attitudes to risk taking in medical decision making among British, Dutch and Belgian general practitioners. Br J Gen Pract 1990; 40: 134-36. 2. Griffiths R, ed. Dealing with risk. Manchester: Manchester University Press, 1982. 3. Editorial. The selling of patients’ data. 1989; ii: 1078. 4. Eddy DM. Variations in practice: the role of uncertainty. In: Dowie J, Elstein A, eds. Professional judgement: a reader in clinical decision making. Cambridge: Cambridge University Press, 1988: 45-59. 5. Sackett D, Haynes RB, Tugwell P. Clinical epidemiology: a basic science of clinical medicine. Boston: Little, Brown, 1985. 6. Fox J. Knowledge and judgement in decision making. In: Brooke J, Rector A, Sheldon M, eds. Decision making in general practice. London: Macmillan, 1985: 107-18. 7. Schon D. From technical rationality to reflection-in-action. In: Dowie J, Elstein A, eds. Professional judgement: a reader in clinical decision making. Cambridge: Cambridge University Press, 1988: 60-77. 8. Mesker J, Mesker P. Some difficulties in comparing morbidity between countries. J R Coll Gen Pract 1979; 29: 92-96. 9. Payer L. Medicine and culture. London: Gollancz, 1989. 1. Grol
will encourage parents and professionals to observe children carefully as they come to walk. Those skilled in surveillance will be able to assess the clinical picture in children who do walk late and offer developmental guidance or further
referral as appropriate. 1. Neligan G, Prudham D. Norms for four standard developmental milestones by sex, social class and place in family. Dev Med Child Neurol 1969; 11: 413-22. 2. Colver AF, Steiner H. Health surveillance of pre-school children. Br Med
J 1986; 293: 258-60. 3. Chaplais J de Z, MacFarlane JA. A review of four hundred and four late walkers. Arch Dis Child 1984; 59: 512-16. 4. Johnson A, Goddard O, Ashurst H. Is late walking a marker of morbidity? Arch Dis Child 1990; 65: 486-88. 5. Smith RA, Rogers M, Bradley DM, Sibert JR, Harper PS. Screening for Duchenne muscular dystrophy. Arch Dis Child 1989; 64: 1017-21. 6. Standing Medical Advisory Committee and Standing Nursing and
Midwifery Advisory Committee. Screening for detection of congenital dislocation of the hip. London: DHSS, 1986. 7. Robson P. Screening for children. Developmental Health 1978; 98: 231-37.
paediatrics. J R
Soc
TAKING RISKS IN GENERAL PRACTICE It might be thought that a good general practitioner should never take risks, but Grol and colleagues have lately argued that doctors who seek to minimise uncertainty and to avoid risks in primary care are acting irrationally. These researchers compare the reported attitudes to risk-taking of general practitioners in Belgium, Holland, and the UK and suggest that Dutch general practitioners are more willing to take risks in clinical decision making because their vocational training makes them aware of the dangers of defensive medicine. These conclusions are open to the criticisms that reported attitudes do not necessarily reflect clinical practice (the evidence presented to substantiate this link is tenuous) and that the role ascribed to educational methods is speculative. Nevertheless, the paper does raise several important issues. It is potentially misleading to label a decision to "wait and see" after careful clinical assessment as "risk taking", a phrase that suggests carelessness and irresponsibility. General practitioners face the unenviable problem of needing to assess the likelihood of serious disease in a population in which such events are rare. Not only is there a problem of maintaining vigilance but also the diagnostic value of symptoms and signs in general practice is much less than in hospital medicine. A clinical sign with 90% sensitivity and 95 % specificity has a predictive value of 95 % if the underlying prevalence of disease is 50 %, but only 15 % if the prevalence is 1%. In primary care, knowledge of the proportion of patients with a certain symptom who do not have serious disease becomes more important than knowledge of the proportion who do. If general practitioners adopt the same diagnostic and investigative thresholds as do their hospital colleagues they will generate much suffering through false alarms. So, how should general practitioners achieve the correct balance between reassurance and diagnostic intervention? The issue is the appropriate management of low-level risks, a task that has intrigued epidemiologists and environmental scientists for some years and about which there have been many reports 2 The first step in risk management is simple: quantify the risk. This means assessing the significance of symptoms and signs in the community rather than working backwards from descriptions in medical textbooks which are
based on hospital case-series. In the UK introduction of on-desk computers in general practice surgeries has made this assessment possible for the first time, and it is tragic that the Government has not provided adequate support for this development in England and Wales, preferring to leave the task to commercial organisations funded by the
pharmaceutical industry. The Dutch seem to have little doubt that if one can provide better data about disease prevalence and the diagnostic significance of symptoms and signs in the community, general practitioners could be taught to make better clinical decisions. It is certainly true that doctors are ill at ease with uncertainty and Eddy has argued cogently that clinical practice would be much improved if physicians were educated to be more numerate in the sense of "learning the language" of probability.4 Pioneering work at McMaster has shown that probability theory can be used successfully in a clinical context.5 So, although there is no firm evidence that numerate doctors are better doctors at providing immediate clinical care, and the true value of numeracy may lie in planning and evaluating practice protocols for the management of disease rather than in making instant decisions in the surgery, some progress has been made already in translating theory into practice. It is also possible that knowledge-based computer systems, which can generate diagnostic hypotheses and use probabilistic data without exposing probabilistic reasoning to the doctorsmay soon revolutionise clinical practice. The most important element in medical decision making is framing the question-selecting the salient information from the morass.7 To achieve this in general practice, as in hospital medicine, the patient must be listened to and examined carefully. It is clearly an unacceptable risk not to do this. But in taking a decision to act on the information elicited (even if the action is a diagnostic test) the general practitioner must be more aware than hospital colleagues of the danger of false-positive information. The acceptable and necessary "risk" taken is the selection of a higher threshold for action. Despite Grol’s paper, it is not established that British doctors set this threshold higher, and therefore take more risk, than do their Dutch colleagues. A comparative study from general practice 10 years ago provided no evidence for this notion,8 and Payer’s overview of medicine and culture in Europe characterised the British as "doing less of everything".9 However, it is clear that the Dutch are looking ahead and teaching primary care doctors to be numerate in the belief that it will help them to deal better with uncertainty and low-level risk in the future. R, Whitfield M, De Maesener J, Mokkink H. Attitudes to risk taking in medical decision making among British, Dutch and Belgian general practitioners. Br J Gen Pract 1990; 40: 134-36. 2. Griffiths R, ed. Dealing with risk. Manchester: Manchester University Press, 1982. 3. Editorial. The selling of patients’ data. 1989; ii: 1078. 4. Eddy DM. Variations in practice: the role of uncertainty. In: Dowie J, Elstein A, eds. Professional judgement: a reader in clinical decision making. Cambridge: Cambridge University Press, 1988: 45-59. 5. Sackett D, Haynes RB, Tugwell P. Clinical epidemiology: a basic science of clinical medicine. Boston: Little, Brown, 1985. 6. Fox J. Knowledge and judgement in decision making. In: Brooke J, Rector A, Sheldon M, eds. Decision making in general practice. London: Macmillan, 1985: 107-18. 7. Schon D. From technical rationality to reflection-in-action. In: Dowie J, Elstein A, eds. Professional judgement: a reader in clinical decision making. Cambridge: Cambridge University Press, 1988: 60-77. 8. Mesker J, Mesker P. Some difficulties in comparing morbidity between countries. J R Coll Gen Pract 1979; 29: 92-96. 9. Payer L. Medicine and culture. London: Gollancz, 1989. 1. Grol
