1464

VIEWPOINT

Doctors and priorities

You round a bend in the road and are suddenly presentedwith a motorbike upside-down in the ditch. There are twocasualties-one bleeding profusely from a wound in thethigh and the other clutching his shoulder, which he says issore. Which of the two is in greater need of assistance?

I take it that we would all give priority to the man who isbleeding to death: but why? At a time when doctors areabsolving themselves for responsibility for deciding onpriorities,’ it is worth spending a few moments analysing thissimple scenario. Major haemorrhage is immediately life-threatening ; a sore shoulder is not. So the first point aboutour instinctive choice of priorities is that we assess the

prognosis if nothing is done, and accord higher priority tothe condition with the worse outcome. But we also know

that, if we stop the bleeding, all will be well: we evaluate boththe prognosis of the condition and the likely outcome oftreatment.

For a health authority fulfilling its role of determiningpriorities, the same two criteria can be used in making adecision-severity, as judged by likely outcome withoutintervention; and the effectiveness of treatment. Some

development of these criteria is of course necessary when thescenario is not two casualties but a population of 300 000 ormore people, but the fundamental principles remain true.The first necessary refinement is an open

acknowledgment that health authorities almost always takedecisions not about individuals but about groups of patients.Typically the choice is between shutting surgical beds andreducing family planning clinics or not funding a

psychogeriatric service-that is, between the group ofpeople who need surgery, or young people who need familyplanning services, or old people with psychiatric problems.As a result the judgment of how severe a condition is has tobe based on the spectrum of severity seen within a group ofpeople, rather than actual clinical assessment of individualpatients.

At first sight a statistical approach based on spectrum ofseverity may seem alien to clinical practice, which above allelse deals with the individual patient. But in fact anyjudgment about prognosis, even in the individual patient, isa statistical judgment, a judgment about probable outcome,with no guarantee of rightness in any particular case. Themotorcyclist with a sore shoulder might actually haveruptured his spleen and been in greater need than wasrealised. In the same way, a health authority which decidesto give low priority to patients with varicose veins2 is makinga statistical judgment about the likely outcome for most suchpatients: but the judgment may be wrong and seriouscomplications may develop unexpectedly.The second modification required to one’s roadside

assessment of priorities is to acknowledge that in the realworld one cannot do everything for everybody: the best youcan do is make the most of the resources you have. More

explicitly, it is not just the effectiveness of treatment that

ADDRESS North East Essex Health Authority, Turner Road,Colchester C05 4JR. UK (E G. Jessop, DM)

counts, but how much it costs. It is better to give cheapeffective treatment to ten patients than spend the sameresources-whether of money, staff, or operating time-onone treatment of dubious efficacy. (An exception may bemade for the cost of research needed to explore efficacy.)

I would argue therefore that two criteria-severity andcost-effectiveness--can form the basis of logical andcoherent decisions between competing priorities in thehealth service. One must of course also accept that in humanaffairs logic and coherence are not all that matter, and publicopinion may dictate other priorities such as short waiting-lists for elective surgery (often low on the severity scale) or anational screening programme for cervical cancer (anexpensive way of saving life 3).

Finally let us not forget that the patient in greatest needmay be neither the one bleeding from a wound in the thighnor the one with a sore shoulder, but the one you haven’tnoticed who was thrown over the hedge by the force of theimpact and is now quietly dying of an obstructed airway.

REFERENCES

1. Beecham L. Doctors should not decide on priorities. Br Med J 1991; 302:1026.

2. Dean M. End of a comprehensive NHS? Lancet 1991; 337: 351-52.3. Roberts CJ, Farrow SC, Charny MC. How much can the NHS afford to

spend to save a life or avoid a severe disability? Lancet 1985; i: 89-91.

BOOKSHELF

Topley and Wilson’s Principles of Bacteriology,Virology and Immunity

8th edition-Edited by Tom Parker and Leslie H. Collier.London: Edward Arnold/Philadelphia: Decker. 1990. Pp 2736(4 vols + index). D95/$595. ISBN 0-713145943.

Topley and Wilson first appeared in 1929 and, reprintedthree times in six years, soon established itself as a classic.

Subsequent editions have shown an inexorable increase insize; this, the eighth, weighs in at a massive 9-5 kg-2736pages in five volumes, with over 3 million words by 125authors. The first volume deals with general bacteriologyand immunity, the second with systematic bacteriology, thethird with bacterial diseases, and the fourth with virology,the final volume is an index. The text has been extensivelyrevised since the seventh edition in 1983, but most of theincrease in bulk is due to a greatly improved format: the pagesize has increased (21-5 x 27-3 cm instead of 18-5 x 24-5 cm)and the new layout is clear, modern, and handsome. We mayeven become fond of (though surely never love) the luridgreen, red, black, and gold covers.But the text is the thing, and the new edition is a triumph.

The editors state that Topley and Wilson is meant to besomething between a textbook and a monograph, witharguments presented in such a way that the reader can cometo his or her own conclusions, and that they do not attemptto be completely comprehensive or to provide references forevery statement. Special features of this and other editionsare paragraphs in small print that summarise recent

advances or contentious theories (T & W addicts alwaysread these first), historical reviews of early work to show thedevelopment of ideas in microbiology, and brief accounts ofrelevant infections in animals. The text is remarkably up to

1465

date, but in many cases the authors have wisely avoidedexcess detail on rapidly changing subjects, and instead referthe reader to recent reviews. Much information iscondensed into admirably clear tables which also give keyreferences. A final hallmark of Topley and Wilson is theremarkable editing of so many contributions into a

consistently clear and unobtrusive English style-the bookis a pleasure to read and it is rarely dull. Unlike mosttextbooks, if you dip into it quickly for a few facts, you arelikely to be seduced into reading far more than you intended,often on quite different subjects.

It is as difficult for one person to review the contents ofthis book in detail as it would be for one person to write it.The subjects with which I am most familiar are coveredwell, though I was left wishing the authors had been alloweda little more space to expand. On the other hand, chapters ontopics I was unsure of made me realise the extent of myignorance, but left me immeasurably better informed andknowing where to go for further reading. In other words, thelatest Topley and Wilson succeeds in doing exactly what itsets out to do. There are some minor drawbacks. For a bookof this size a few more illustrations would not go amiss;additional line drawings, in particular, would greatlyenhance the text. There has been a welcome move to arrangebacterial infections more by system and by syndrome than inprevious editions, but it is a pity that virology is still so

starkly separated from the rest of microbiology. Techniquesin bacteriology and virology are converging, and it would begood to see Topley and Wilson take a lead in helping to breakdown the artificial divisions between them. Finally, thehistorical reviews have been severely cut: many readers willbe irritated by cross-references to previous editions for morebackground information, especially when these are notaccessible. Although space is clearly at a premium thegradual loss of this unique archival material, unavailableelsewhere, erodes some of the character and quality of thebook. Perhaps the history can be restored in the (six-volume ?) ninth edition.

Essential for professionals in microbiology, immunology,communicable diseases, public health, and epidemiology,the new Topley and Wilson is also a constant source of

pleasure for anyone who enjoys scholarship and the art offine scientific writing. Take out a mortgage and buy it.

Department of Microbiology,UMDS, Guy’s Hospital,London SE1 9RT, UK GARY FRENCH

Breast Cancer: the Decision to Screen

Patrick Forrest. London: Nuffield Provincial Hospitals Trust.1990. Pp 233. 15. ISBN 0-900574747.

So many disciplines are involved in the theory andpractice of screening for breast cancer that it is difficult for aworker in any one of them to have a comprehensiveunderstanding of the subject. The extensive published workcomprises a wealth of papers written with their own

particular slants by radiologists, pathologists, surgeons,nurses, epidemiologists, sociologists, economists, and

ethicists, and selectively read by the same professionalgroups. These varied contributions are inevitably tingedwith the priorities and interests of the author’s discipline,frequently coupled with the emotional overlay that creepsinto any discussion of breast cancer.But here at last is a monograph that stands back and gives

an overview, based on a thorough understanding of theprinciples of each specialty as applied to screening for breast

cancer. Moreover, it is written in a concise but accessiblestyle that informs and educates while sustaining interest andnarrative flow. The natural history of breast cancer, furtherelucidated almost daily by advances in our knowledge ofmolecular biology, is thoughtfully discussed. By comparisonwith the fine precision of this intracellular research,screening huge numbers of symptomless women bymammography (even given the relative sophistication ofmodem mammographic techniques) seems a block-busterapproach for controlling breast cancer. But, as Sir Patrickclearly explains, to evaluate screening there is no alternativeto epidemiological research, which involves keeping track oftens of thousands of women randomly allocated to the offerof screening or to an unscreened control group: this is theonly valid way to test the value of screening. The variousscreening trials are comprehensively reviewed, with theconclusion that mammographic screening substantiallyreduces breast cancer mortality in women aged over 50.Evidence on the risks, unwanted side-effects, and costs isalso fairly presented.

In his prologue, Sir Patrick invites the reader to decide, onthe basis of these facts, whether the decision to implementmass population screening for breast cancer was, for theUnited Kingdom, a correct one. He concludes the book withhis own verdict, that "screening mammography can prolonglife to a greater extent than any other change in the

management of breast cancer. To dispense with it, withouthaving something better to put in its place, would be a bravedecision".

Cancer Screening Evaluation Unit,Institute of Cancer Research,Sutton SM2 5NG, UK JOCELYN CHAMBERLAIN

A Basic Science Primer in OrthopaedicsEdited by Felix Bronner and Richard V. Worrell. Baltimore:Williams and Wilkins. 1991. Pp 253. £39.25. ISBN 0-68301076X.

Bronner and Worrell rightly note that there is

"increasingly widespread interest in bone and hard tissuefunction and structure evinced by many specialties andprofessions", and set out to explain briefly the scientificprinciples that underlie orthopaedics. The proximal two-thirds of this short primer make interesting and informativereading and represent an excellent introduction to skeletonresearch for basic scientists and for orthopaedic trainees,particularly those just about to sit final specialistexaminations. Their more senior colleagues will also findthis section a useful reminder of the breadth of recentresearch in the specialty—as shown in the chapters onembryology of the musculoskeletal system and mineralmetabolism of bone. The text is clear and the diagrams andphotographs are mostly of excellent quality, but the booksuffers from a lack of uniformity; for example, the ratheruninteresting and uninformative summaries that concludesome chapters appear at the beginning of others.

In the last third of the book the editors ambitiouslyattempt to cover clinical aspects of diseases of bone andarticular cartilage in just under 50 pages. Predictably, theyfail: this part of their skeleton needs much more flesh orshould be amputated in a future edition. Nevertheless, theearlier chapters will be of interest to all clinicians who treatpatients with bone disease.

Department of Surgical Sciences (Orthopaedics),Guy’s Hospital,London SE1 9RT, UK JOHN SPENCER