telephone directory, and if you can't telephone or visit a branch then you can write. I hope that this letter will enable us to reach those junior doctors who feel under stress, lonely, or suicidal. I would like to say to them, please remember that the Samaritans are there for you to talk to and share your feelings. Don't let things get too much. Pick up a phone first. ANONYMOUS The Samaritans, Winchester and District Branch, Winchester, Hampshire 1 Aitken H. Someone to turn to. BMJ 1991;301:185. (19 January.)
evidence of repeated audits that will 'close the feedback loop."' Furthermore their only reference to the need for standards is to state that "many general practitioners thus already have entry points for starting the process ofsetting standards." Proper educational benefit will be achieved and clinical standards improved only if we avoid confusion and maintain rigorous intellectual discipline by adhering to precise definitions. We should not label any studies as medical audit unless they are assessed against the paradigm of the audit cycle, with explicit standards and measured changes and preferably categorised in terms of structure, process, or outcome.
obvious need for response rates greater than 800/% when examining relations between two or more variables. A good response makes interpretation easier, but each study must be evaluated on its merits. Otherwise, useful information would be needlessly thrown away. DAVID COGGON CHRISTOPHER MARTYN Mvedical Research Council Environmental Epidemiology Unit, Southampton S09 4XY I Evans SJW. Good surveys guide. (9 February.)
BMJ1 1991;302:302-3.
GUY HOUGHTON Birmingham B28 8BG
Testing for HIV antibodies
Pulmonary embolism SIR,-Minerva reports that mortality in Britain from pulmonary embolism is twice as high in women as it is in men.' This is confirmed by the published figures for England and Wales for 1988,2 with deaths of 485 men and 856 women being assigned to this underlying cause (ICD (ninth revision) 415. 1). Death rates from pulmonary embolism are much higher in older people than in younger people, and differences between men and women change when the risk at different ages is considered. Deaths assigned to pulmonary embolism per million population by age and sex: England and Wales,
19882
All ages Men
20
Women
33
Age (years) 85 1
5
16
67
210
461
4
12
61
218
497
The table shows that age specific rates in 1988 for men were similar to those for women over the whole range. This apparent contradiction reflects differences in the age structure of the population, which comprises more older women than older men. Different conclusions can thus be drawn about the sex differential in mortality from pulmonary embolism, depending on whether the overall rate for each group or the chances of dying at particular ages are considered.
I Webb SJ, Dowell AC, Heywood P. Survey of general practice audit in Leeds. BMJ 1991;302:390-2. (16 February.) 2 Royal College of Physicians of London. Medical audit: a first
report. London: RCP, 1989. 3 Standing Committee on Postgraduate Medical Education. Medical audit: the educational implications. London: SCOPME, 1989.
Preventing fraud SIR,-Ms Jane Smith suggested that the Royal College of Physicians is in a powerful position to prevent fraud because its fellows are deans, professors, chairmen of ethics committees, and chairmen of appointmient committees.' The Royal College of Physicians has another powerful arm in the Faculty of Pharmaceutical Medicine. It has regrettably been a large part of the workload of pharmaceutical physicians to assess the quality of research and to identify that which is unusable owing to either fraud or other reasons (usually poor record keeping), which are more common. If external audit of research was encouraged in academic units (as is required now for drug company studies) then inadequate research technique would not need to be synonymous with fraud, although the results of the research would need to be withdrawn. I am sure that the pharmaceutical physicians will be pleased to offer their assistance in discussing ways that this could be done. GWYN THOMAS BMA Pharmaceutical Physicians Group Committee, London WC1H 9JR
T L F DEVIS
Office of Population Censuses and Surveys, London WX'C2B 6JP 1 Anonymous. Views. BMJ 1991;302:188. (19 January.) 2 Office of Population Censuses and Surveys. Mortality sitaistzics:
cause 1988. London: HMSO, 1990. (DH2/15.)
Audit in general practice SIR,-One of the biggest problems with the introduction of medical audit has been the plethora of definitions and the difference of opinions about what it entails. This problem was highlighted by the study by Dr Sheila J Webb and colleagues.' The audit activities they describe seem to be largely confined to exercises in data collection, practice analysis activity, and the development of prescribing or disease management protocols. Though all these procedures are invaluable in promoting good practice and may be used as a foundation for medical audit it is surely wrong to call them audits as such. In no way do they conform to the model of the audit process as set out by the Royal College of Physicians2 and amplified by the Standing Committee on Postgraduate Education'-namely, observe practice, set a standard of practice, compare observed practice with the standard, implement change, and observe practice after changes have been implemented. The authors seem to appreciate this distinction in terminology when they say that "there was little
660
I Smith J. Preventing fraud. BMJ 1991;302:362-3. (16 Februanr.)
Good surveys guide SIR,-Professor S J W Evans rightly emphasises the value of high response rates in surveys, although, as he points out, samples with lower response rates can be informative.' He describes how bounds can be placed on prevalence estimates by assuming extreme bias in non-responders. Interpretation may also be helped by examining the reasons for non-response, both when estimating prevalences and when looking at associations between variables. For example, consider a survey in a general practice population to explore the associations between myopia and educational attainment, and suppose that there is an incomplete response because some subjects have changed address without informing the practice and others are persistently not at home when visited. In this case the relation between myopia and education is unlikely to be very different in responders and non-responders. Thus the survey's results might be accepted despite the incomplete response. Of course, this assessment entails subjective judgments, but so does extrapolation from the study population (that is, patients of a few general practitioners) to the wider target population in which the results will be applied. Professor Evans goes too far when he asserts an
SIR,-Dr Tony Delamothe reports the increase in the number of patients identified with heterosexually acquired HIV infection.' It remains uncertain, however, whether this indicates a real change in seroprevalence or is due to increased uptake of HIV antibody testing by previously
infected individuals. In March 1990 we began a study to examine this question in heterosexual patients attending our genitourinary medicine clinic requesting an HIV antibody test. We aimed at repeating the tests at six monthly intervals to determine any change in HIV seroprevalence. Unfortunately the study failed because few heterosexuals were willing to volunteer for repeated testing. In addition, the geographical mobility of many people attending genitourinary medicine clinics made the planned two year follow up impossible. To examine the reasons for the reluctance to request an HIV test, we investigated 200 consecutive patients (100 men and 100 women), who had declined a test. We used a self administered questionnaire that used a visual analogue scale to determine agreement or disagreement with statements about HIV testing.2 The results were collected anonymously for each sex. Men were particularly worried about confidentiality, whereas women expressed more concern about being unable to cope with a positive result (table). Both sexes were concerned about the effect of having a test, whether the result was positive or negative, on the prospects for life insurance and mortgage applications. More men than women were worried about having to admit things in their past to their partners and, similarly, were certain that they were at no risk of having HIV antibodies. Overall, only 7% of patients agreed with the response that "Heterosexuals don't get HIV." Our study shows that although people attending genitourinary medicine clinics have a high awareness of the potential for heterosexual transmission Reasons for declining HIV antibody test No who responded 'very much on my mind" Statement I'm worried about the financial implications of having a test (insurance policies, mortgages, etc) I think the result mav be positive anid couldn't cope with it I'm worried about my partner's reaction if I said I was having an HIV test I don't want to know the result as there is no cure I would have to admit things to my partner about my past I think that I am at no risk of being HIV seropositive I'm worried about the confidentiality of the result I don't think heterosexuals can get HIV I always have safe sex, so why bother
BMJ VOLUME 302
Men (n= 100)
Women (n= 100)
47
32
12
40
21
24
28
18
20
2
23 64 2
18
12 20
16 MARCH 1991
of HIV, many decline HIV testing. The objections to testing that we identified could be reduced by
strategies designed to improve patients' knowledge and awareness of specific issues. With regard to the financial implications, the Association of British Insurers has indicated that having an HIV test as part of a recognised screening programme, such as screening before blood donation or as part of antenatal care, will not adversely affect insurance policies, provided that the result is negative.2 We believe that this should be extended to cover all HIV testing and that this assurance needs to be widely publicised. Furthermore, we believe that advertising and counselling that emphasise the confidentiality of test results and the benefits of earlier treatment of HIV infections may increase the acceptability and uptake of HIV antibody testing among heterosexuals. P D KELL M A CRACKNELL S E BARTON
A G LAWRENCE St Stephen's Clinic, London Swlio 9TrH I Delamothe T. New AID)S figures.
BAIj 1991;302:197.
(26 January.) 2 Association of British Insurers. ABI factfile: AIDS and insurers.
London: ABI, 1988. 3 Volberding PA, Lagakos SW, Koch MA, et al. Zidovudine in asymptomatic human immunodeficiency virus infection. N Englj Med 1990;322:941-9.
The Jarman index SIR,-Dr Roy A Carr-Hall and Mr Trevor Sheldon' suggest that the function of the deprivation payments is twofold: to compensate general practitioners for increased workload in socially deprived areas and to act as an incentive to work in these areas, where income may be lower owing to failure to meet targets. In east London the payment achieves neither of these aims. General practitioner workload is a nebulous concept comprising some elements that are easily measurable, such as consultation rates, and others that are much harder to quantify, such as fears of aggression and violence and inadequate staffing and premises. To construct an index that could be validated nationally against such a subjective notion would be impossible. Perceived pressures of work do not relate to the index currently applied. Department of Health figures show that many general practitioners have fallen short of targets in areas where no deprivation payments are made, including areas of heavy workload. Clearly, the payments are not effectively compensating for this. In addition, the index does not truly reflect the characteristics of an area. The variables from which it is calculated can be updated only every 10 years as census data become available. My practice is on the Isle of Dogs in London's docklands, where the structure of the population has changed enormously since 1981 and will continue to change. This is unusual but not unique. Currently, deprivation payments are made for all patients on the list. This contrasts with an adjoining practice where, subjectively, workload is greater but not all patients live within an area that qualifies for payments. My partner and I are in the fortunate position of receiving a guaranteed minimum salary from the family health services authority, which amounts to average net remuneration. Our type 2 practice allowance permits the authority to reimburse the expenses of a new practice in this area of rapid population growth. Irrespective of the level of deprivation payments or the targets we attain, we will not be financially penalised for spending time dealing with the problems that patients present to us.
No form of remuneration will ever be completely fair, but introducing a salaried option would
BMJ VOLUME 302
16 MARCH 1991
reasonably reward work done and get away from payments that may not reflect workload and do not compensate for failure to reach targets. JOANNA RICHARDSON
Island Health, London E14 3BQ I Carr-Hall RA, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ7 1991;302:393-6. (16 February.)
SIR, -Dr George Davey Smith's editorial' and the papers by Dr Robin J Talbot2 and Dr Roy A CarrHill and Mr Trevor Sheldon3 suggest that the Jarman index may be inappropriate for allocating health service resources and paying general practitioners. My colleague and I showed that the Jarman scores correlate more weakly (over 928 postcode sectors in Scotland) with mortality and the measure of permanent sickness in the census than does either the Scottish or Townsend measure.' Jarman scores are correlated more highly with hospital discharges and bed days than are the other two measures because of the influence of the "lone elderly" variable. Readers interested in this debate may wish to examine these data; a fuller dataset is available on request. Needs for primary care are not all determined by mortality and morbidity, but, nevertheless, a measure that shows deficits in respect of these does not provide confidence that it offers an equitable basis for the allocation of enhanced payments to doctors. Areas with high proportions of young children and of people moving into them may benefit at the expense of areas with more severe health problems. The Jarman index needs to be reconstructed not discarded, and the next sweep of the general practitioner workload survey should be designed to assist in its development.5 VERA CARSTAIRS Health Services Research Networks, Edinburgh EFH1 9J T I Smith C,D. Second thoughts on the Jarman index. BMJ 1991;302:359-60. (16 February.) 2 Talbot RJ. Underprivileged areas and health planning: implications of use of Jarman indicators of urban deprivation. BMJ 1991;302:383-6. (16 February.) 3 Carr-Hall RA, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ 1991;302:393-6. (16 February.) 4 Carstairs V, Morris R. Deprivation and health. BMJ 1989;229: 1462. 5 Royal College of General Practitioners, Office of Population Censuses and Surveys, Department of Health and Social Security. Morbidity statisticsfrom general practice, third national study. London: HMSO, 1986. (Series MB.)
SIR,-The arguments of Dr Roy Carr-Hill and Mr Trevor Sheldon that the underprivileged area index is neither clear nor comprehensible' are considerably reinforced by the differential positive skewness of its eight constituent variables. According to my calculations of a skewness statistic, the transformation Jarman uses produces normality only for the "unskilled" variable. Moreover, the three most skewed variables-ethnic minorities, residential mobility, and overcrowding-are precisely the ones given the lowest weights by general practitioners. As skewness introduces additional hidden (but unknown) weights into the calculation of scores,2 the explicit weights of the general practitioners are being at. least partly neutralised and distorted. This helps to explain why the Jarman index is popularly perceived to favour areas with relatively large proportions of ethnic minority residents. In his comments on my recent paper' Professor Jarman has argued that skewness is less problematic if the histograms of the eight variables are weighted by ward populations. His argument implies, however, that the underprivileged area scores should have been calculated using population weighted means and standard deviations for
those variables. Not surprisingly, the population weighted underprivileged area scores I recently calculated (and not in my paper) differ from those in current use. So should the Department of Health be using them to identify deprived wards? Comparing the underprivileged area and Townsend4 indexes' ranking of all 9265 wards in England and Wales, and applying deprivation payment scales for 1991, reveals a more detailed picture than that painted in Dr Robin J Talbot's article.' Although both Professor Jarman's index and Townsend's favour different areas, both cover both northern and southern districts, thus showing that the north-south divide is not clear cut. At the ward scale the Townsend index is more sensitive to deprivation on estates housing overspill populations from the inner cities, while Jarman's index ranks some coastal retirement areas as "deprived" because ther have many elderly people living alone. In some respects criticisms of Professor Jarman are too severe. Firstly, critics complain that census information is out of date, but they do not propose better sources of data of uniform quality throughout Britain. Secondly, Dr Talbot rightly argues that identifying deprived enumeration districts would be preferable to using wards, but he fails to recognise the substantial inaccuracies involved in matching patients' postcodes to such small areas.`x It is also unfair to blame Professor Jarman for the way his underprivileged area scores have been used by the government's health departments. The threshold scores are not only intuitively implausible but are at odds with the continuous gradation of underprivileged area scores. The abrupt changes in payments imply a degree of precision and consensus in demarcating classes of deprivation-or general practitioner workloadimpossible to achieve from census questions and data aggregation. Until, as Dr Carr-Hill and Mr Sheldon conclude, policy is based on the results of scientific tests, a tapered system of deprivation payments would be more sensible. Such a scheme, starting at £1 for the arbitrary score of 16 and proceeding in increments of 10 pence for every unit increase in the score,3 would involve much the same national expenditure (in England) as at present-but may be unwelcome to those general practitioners who profit from the present stepped payment system. MARTYN L SENIOR
Department of Geography, University of Salford, Salford M5 4WT 1 Carr-Hill R, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ 1991;302:393-6. (16 February.) 2 Thunhurst C. The analysis of small area statistics and planning for health. Statistician 1985;34:93-106. 3 Senior ML. Deprivation payments to GPs: not what the doctor ordered. Environment and Planning: Government and Policy
1991;9:61-7. 4 Townsend P, Phillimore P, Beattie A. Inequalities in health in the Northern region: an interim report. Bristol: University of Bristol; Newcastle: Northern Regional Health Authority, 1986. 5 Talbot RJ. Underprivileged areas and health care planning: implications of use of Jarman indicators of urban deprivation. BM7 1991;302:383-6. (16 February.) 6 Gatrell AC. On the spatial representation and accuracy of address-based data in the United Kingdom. International Journal of Geographical Information Systems 1989;3:335-48. 7 Gatrell AC, Dunn CE, Boyle PJ. The relative utility of the central postcode directory and pinpoint address code in applications of geographical information systems. Lancaster University: North West Regional Research Laboratory, 1990. (Research report No 15.) 8 Jarman B. Social depnrvation and health service funding. London: Imperial College of Science, Technology, and Medicine, 1990. (Papers in science, technology, medicine, and public policy No22.)
I needed to see my son SIR,-MS Sheila Awooner-Renner's account of her visit to her dead son is a moving reminder to all of us in emergency medicine.' Sadly, the hospital staff confused their need to confirm identification
661
evidence of repeated audits that will 'close the feedback loop."' Furthermore their only reference to the need for standards is to state that "many general practitioners thus already have entry points for starting the process ofsetting standards." Proper educational benefit will be achieved and clinical standards improved only if we avoid confusion and maintain rigorous intellectual discipline by adhering to precise definitions. We should not label any studies as medical audit unless they are assessed against the paradigm of the audit cycle, with explicit standards and measured changes and preferably categorised in terms of structure, process, or outcome.
obvious need for response rates greater than 800/% when examining relations between two or more variables. A good response makes interpretation easier, but each study must be evaluated on its merits. Otherwise, useful information would be needlessly thrown away. DAVID COGGON CHRISTOPHER MARTYN Mvedical Research Council Environmental Epidemiology Unit, Southampton S09 4XY I Evans SJW. Good surveys guide. (9 February.)
BMJ1 1991;302:302-3.
GUY HOUGHTON Birmingham B28 8BG
Testing for HIV antibodies
Pulmonary embolism SIR,-Minerva reports that mortality in Britain from pulmonary embolism is twice as high in women as it is in men.' This is confirmed by the published figures for England and Wales for 1988,2 with deaths of 485 men and 856 women being assigned to this underlying cause (ICD (ninth revision) 415. 1). Death rates from pulmonary embolism are much higher in older people than in younger people, and differences between men and women change when the risk at different ages is considered. Deaths assigned to pulmonary embolism per million population by age and sex: England and Wales,
19882
All ages Men
20
Women
33
Age (years) 85 1
5
16
67
210
461
4
12
61
218
497
The table shows that age specific rates in 1988 for men were similar to those for women over the whole range. This apparent contradiction reflects differences in the age structure of the population, which comprises more older women than older men. Different conclusions can thus be drawn about the sex differential in mortality from pulmonary embolism, depending on whether the overall rate for each group or the chances of dying at particular ages are considered.
I Webb SJ, Dowell AC, Heywood P. Survey of general practice audit in Leeds. BMJ 1991;302:390-2. (16 February.) 2 Royal College of Physicians of London. Medical audit: a first
report. London: RCP, 1989. 3 Standing Committee on Postgraduate Medical Education. Medical audit: the educational implications. London: SCOPME, 1989.
Preventing fraud SIR,-Ms Jane Smith suggested that the Royal College of Physicians is in a powerful position to prevent fraud because its fellows are deans, professors, chairmen of ethics committees, and chairmen of appointmient committees.' The Royal College of Physicians has another powerful arm in the Faculty of Pharmaceutical Medicine. It has regrettably been a large part of the workload of pharmaceutical physicians to assess the quality of research and to identify that which is unusable owing to either fraud or other reasons (usually poor record keeping), which are more common. If external audit of research was encouraged in academic units (as is required now for drug company studies) then inadequate research technique would not need to be synonymous with fraud, although the results of the research would need to be withdrawn. I am sure that the pharmaceutical physicians will be pleased to offer their assistance in discussing ways that this could be done. GWYN THOMAS BMA Pharmaceutical Physicians Group Committee, London WC1H 9JR
T L F DEVIS
Office of Population Censuses and Surveys, London WX'C2B 6JP 1 Anonymous. Views. BMJ 1991;302:188. (19 January.) 2 Office of Population Censuses and Surveys. Mortality sitaistzics:
cause 1988. London: HMSO, 1990. (DH2/15.)
Audit in general practice SIR,-One of the biggest problems with the introduction of medical audit has been the plethora of definitions and the difference of opinions about what it entails. This problem was highlighted by the study by Dr Sheila J Webb and colleagues.' The audit activities they describe seem to be largely confined to exercises in data collection, practice analysis activity, and the development of prescribing or disease management protocols. Though all these procedures are invaluable in promoting good practice and may be used as a foundation for medical audit it is surely wrong to call them audits as such. In no way do they conform to the model of the audit process as set out by the Royal College of Physicians2 and amplified by the Standing Committee on Postgraduate Education'-namely, observe practice, set a standard of practice, compare observed practice with the standard, implement change, and observe practice after changes have been implemented. The authors seem to appreciate this distinction in terminology when they say that "there was little
660
I Smith J. Preventing fraud. BMJ 1991;302:362-3. (16 Februanr.)
Good surveys guide SIR,-Professor S J W Evans rightly emphasises the value of high response rates in surveys, although, as he points out, samples with lower response rates can be informative.' He describes how bounds can be placed on prevalence estimates by assuming extreme bias in non-responders. Interpretation may also be helped by examining the reasons for non-response, both when estimating prevalences and when looking at associations between variables. For example, consider a survey in a general practice population to explore the associations between myopia and educational attainment, and suppose that there is an incomplete response because some subjects have changed address without informing the practice and others are persistently not at home when visited. In this case the relation between myopia and education is unlikely to be very different in responders and non-responders. Thus the survey's results might be accepted despite the incomplete response. Of course, this assessment entails subjective judgments, but so does extrapolation from the study population (that is, patients of a few general practitioners) to the wider target population in which the results will be applied. Professor Evans goes too far when he asserts an
SIR,-Dr Tony Delamothe reports the increase in the number of patients identified with heterosexually acquired HIV infection.' It remains uncertain, however, whether this indicates a real change in seroprevalence or is due to increased uptake of HIV antibody testing by previously
infected individuals. In March 1990 we began a study to examine this question in heterosexual patients attending our genitourinary medicine clinic requesting an HIV antibody test. We aimed at repeating the tests at six monthly intervals to determine any change in HIV seroprevalence. Unfortunately the study failed because few heterosexuals were willing to volunteer for repeated testing. In addition, the geographical mobility of many people attending genitourinary medicine clinics made the planned two year follow up impossible. To examine the reasons for the reluctance to request an HIV test, we investigated 200 consecutive patients (100 men and 100 women), who had declined a test. We used a self administered questionnaire that used a visual analogue scale to determine agreement or disagreement with statements about HIV testing.2 The results were collected anonymously for each sex. Men were particularly worried about confidentiality, whereas women expressed more concern about being unable to cope with a positive result (table). Both sexes were concerned about the effect of having a test, whether the result was positive or negative, on the prospects for life insurance and mortgage applications. More men than women were worried about having to admit things in their past to their partners and, similarly, were certain that they were at no risk of having HIV antibodies. Overall, only 7% of patients agreed with the response that "Heterosexuals don't get HIV." Our study shows that although people attending genitourinary medicine clinics have a high awareness of the potential for heterosexual transmission Reasons for declining HIV antibody test No who responded 'very much on my mind" Statement I'm worried about the financial implications of having a test (insurance policies, mortgages, etc) I think the result mav be positive anid couldn't cope with it I'm worried about my partner's reaction if I said I was having an HIV test I don't want to know the result as there is no cure I would have to admit things to my partner about my past I think that I am at no risk of being HIV seropositive I'm worried about the confidentiality of the result I don't think heterosexuals can get HIV I always have safe sex, so why bother
BMJ VOLUME 302
Men (n= 100)
Women (n= 100)
47
32
12
40
21
24
28
18
20
2
23 64 2
18
12 20
16 MARCH 1991
of HIV, many decline HIV testing. The objections to testing that we identified could be reduced by
strategies designed to improve patients' knowledge and awareness of specific issues. With regard to the financial implications, the Association of British Insurers has indicated that having an HIV test as part of a recognised screening programme, such as screening before blood donation or as part of antenatal care, will not adversely affect insurance policies, provided that the result is negative.2 We believe that this should be extended to cover all HIV testing and that this assurance needs to be widely publicised. Furthermore, we believe that advertising and counselling that emphasise the confidentiality of test results and the benefits of earlier treatment of HIV infections may increase the acceptability and uptake of HIV antibody testing among heterosexuals. P D KELL M A CRACKNELL S E BARTON
A G LAWRENCE St Stephen's Clinic, London Swlio 9TrH I Delamothe T. New AID)S figures.
BAIj 1991;302:197.
(26 January.) 2 Association of British Insurers. ABI factfile: AIDS and insurers.
London: ABI, 1988. 3 Volberding PA, Lagakos SW, Koch MA, et al. Zidovudine in asymptomatic human immunodeficiency virus infection. N Englj Med 1990;322:941-9.
The Jarman index SIR,-Dr Roy A Carr-Hall and Mr Trevor Sheldon' suggest that the function of the deprivation payments is twofold: to compensate general practitioners for increased workload in socially deprived areas and to act as an incentive to work in these areas, where income may be lower owing to failure to meet targets. In east London the payment achieves neither of these aims. General practitioner workload is a nebulous concept comprising some elements that are easily measurable, such as consultation rates, and others that are much harder to quantify, such as fears of aggression and violence and inadequate staffing and premises. To construct an index that could be validated nationally against such a subjective notion would be impossible. Perceived pressures of work do not relate to the index currently applied. Department of Health figures show that many general practitioners have fallen short of targets in areas where no deprivation payments are made, including areas of heavy workload. Clearly, the payments are not effectively compensating for this. In addition, the index does not truly reflect the characteristics of an area. The variables from which it is calculated can be updated only every 10 years as census data become available. My practice is on the Isle of Dogs in London's docklands, where the structure of the population has changed enormously since 1981 and will continue to change. This is unusual but not unique. Currently, deprivation payments are made for all patients on the list. This contrasts with an adjoining practice where, subjectively, workload is greater but not all patients live within an area that qualifies for payments. My partner and I are in the fortunate position of receiving a guaranteed minimum salary from the family health services authority, which amounts to average net remuneration. Our type 2 practice allowance permits the authority to reimburse the expenses of a new practice in this area of rapid population growth. Irrespective of the level of deprivation payments or the targets we attain, we will not be financially penalised for spending time dealing with the problems that patients present to us.
No form of remuneration will ever be completely fair, but introducing a salaried option would
BMJ VOLUME 302
16 MARCH 1991
reasonably reward work done and get away from payments that may not reflect workload and do not compensate for failure to reach targets. JOANNA RICHARDSON
Island Health, London E14 3BQ I Carr-Hall RA, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ7 1991;302:393-6. (16 February.)
SIR, -Dr George Davey Smith's editorial' and the papers by Dr Robin J Talbot2 and Dr Roy A CarrHill and Mr Trevor Sheldon3 suggest that the Jarman index may be inappropriate for allocating health service resources and paying general practitioners. My colleague and I showed that the Jarman scores correlate more weakly (over 928 postcode sectors in Scotland) with mortality and the measure of permanent sickness in the census than does either the Scottish or Townsend measure.' Jarman scores are correlated more highly with hospital discharges and bed days than are the other two measures because of the influence of the "lone elderly" variable. Readers interested in this debate may wish to examine these data; a fuller dataset is available on request. Needs for primary care are not all determined by mortality and morbidity, but, nevertheless, a measure that shows deficits in respect of these does not provide confidence that it offers an equitable basis for the allocation of enhanced payments to doctors. Areas with high proportions of young children and of people moving into them may benefit at the expense of areas with more severe health problems. The Jarman index needs to be reconstructed not discarded, and the next sweep of the general practitioner workload survey should be designed to assist in its development.5 VERA CARSTAIRS Health Services Research Networks, Edinburgh EFH1 9J T I Smith C,D. Second thoughts on the Jarman index. BMJ 1991;302:359-60. (16 February.) 2 Talbot RJ. Underprivileged areas and health planning: implications of use of Jarman indicators of urban deprivation. BMJ 1991;302:383-6. (16 February.) 3 Carr-Hall RA, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ 1991;302:393-6. (16 February.) 4 Carstairs V, Morris R. Deprivation and health. BMJ 1989;229: 1462. 5 Royal College of General Practitioners, Office of Population Censuses and Surveys, Department of Health and Social Security. Morbidity statisticsfrom general practice, third national study. London: HMSO, 1986. (Series MB.)
SIR,-The arguments of Dr Roy Carr-Hill and Mr Trevor Sheldon that the underprivileged area index is neither clear nor comprehensible' are considerably reinforced by the differential positive skewness of its eight constituent variables. According to my calculations of a skewness statistic, the transformation Jarman uses produces normality only for the "unskilled" variable. Moreover, the three most skewed variables-ethnic minorities, residential mobility, and overcrowding-are precisely the ones given the lowest weights by general practitioners. As skewness introduces additional hidden (but unknown) weights into the calculation of scores,2 the explicit weights of the general practitioners are being at. least partly neutralised and distorted. This helps to explain why the Jarman index is popularly perceived to favour areas with relatively large proportions of ethnic minority residents. In his comments on my recent paper' Professor Jarman has argued that skewness is less problematic if the histograms of the eight variables are weighted by ward populations. His argument implies, however, that the underprivileged area scores should have been calculated using population weighted means and standard deviations for
those variables. Not surprisingly, the population weighted underprivileged area scores I recently calculated (and not in my paper) differ from those in current use. So should the Department of Health be using them to identify deprived wards? Comparing the underprivileged area and Townsend4 indexes' ranking of all 9265 wards in England and Wales, and applying deprivation payment scales for 1991, reveals a more detailed picture than that painted in Dr Robin J Talbot's article.' Although both Professor Jarman's index and Townsend's favour different areas, both cover both northern and southern districts, thus showing that the north-south divide is not clear cut. At the ward scale the Townsend index is more sensitive to deprivation on estates housing overspill populations from the inner cities, while Jarman's index ranks some coastal retirement areas as "deprived" because ther have many elderly people living alone. In some respects criticisms of Professor Jarman are too severe. Firstly, critics complain that census information is out of date, but they do not propose better sources of data of uniform quality throughout Britain. Secondly, Dr Talbot rightly argues that identifying deprived enumeration districts would be preferable to using wards, but he fails to recognise the substantial inaccuracies involved in matching patients' postcodes to such small areas.`x It is also unfair to blame Professor Jarman for the way his underprivileged area scores have been used by the government's health departments. The threshold scores are not only intuitively implausible but are at odds with the continuous gradation of underprivileged area scores. The abrupt changes in payments imply a degree of precision and consensus in demarcating classes of deprivation-or general practitioner workloadimpossible to achieve from census questions and data aggregation. Until, as Dr Carr-Hill and Mr Sheldon conclude, policy is based on the results of scientific tests, a tapered system of deprivation payments would be more sensible. Such a scheme, starting at £1 for the arbitrary score of 16 and proceeding in increments of 10 pence for every unit increase in the score,3 would involve much the same national expenditure (in England) as at present-but may be unwelcome to those general practitioners who profit from the present stepped payment system. MARTYN L SENIOR
Department of Geography, University of Salford, Salford M5 4WT 1 Carr-Hill R, Sheldon T. Designing a deprivation payment for general practitioners: the UPA(8) wonderland. BMJ 1991;302:393-6. (16 February.) 2 Thunhurst C. The analysis of small area statistics and planning for health. Statistician 1985;34:93-106. 3 Senior ML. Deprivation payments to GPs: not what the doctor ordered. Environment and Planning: Government and Policy
1991;9:61-7. 4 Townsend P, Phillimore P, Beattie A. Inequalities in health in the Northern region: an interim report. Bristol: University of Bristol; Newcastle: Northern Regional Health Authority, 1986. 5 Talbot RJ. Underprivileged areas and health care planning: implications of use of Jarman indicators of urban deprivation. BM7 1991;302:383-6. (16 February.) 6 Gatrell AC. On the spatial representation and accuracy of address-based data in the United Kingdom. International Journal of Geographical Information Systems 1989;3:335-48. 7 Gatrell AC, Dunn CE, Boyle PJ. The relative utility of the central postcode directory and pinpoint address code in applications of geographical information systems. Lancaster University: North West Regional Research Laboratory, 1990. (Research report No 15.) 8 Jarman B. Social depnrvation and health service funding. London: Imperial College of Science, Technology, and Medicine, 1990. (Papers in science, technology, medicine, and public policy No22.)
I needed to see my son SIR,-MS Sheila Awooner-Renner's account of her visit to her dead son is a moving reminder to all of us in emergency medicine.' Sadly, the hospital staff confused their need to confirm identification
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