letters

LETTERS

LETTERS Use of the Internet by oncology most-visited Internet sites were those of cancer centres. patients: its effect on the The Medical Journal of Australia ISSN: 0025-729X 7 Patient perceptions of the impact of doctor–patient relationship October 2002 177 7 332-396

Internet-acquired information on their experience of cancer are summarised in the Julia M L Brotherton,* Stephen J Clarke, ©The Medical Journal of Australia 2002 www.mja.com.au Susan Quine‡ Box. Most patients viewed its impact as *SeniorLetters Resident Medical Officer, Oncology Unit, positive. The advantages of using the Repatriation General Hospital, Concord, NSW Internet reported by patients included its (currently, Public Health Officer, Public Health Training speed, convenience, privacy, currency, and Development Branch, NSW Health); †Senior Staff diversity of viewpoints, and usefulness as a Specialist in Medical Oncology, Sydney Cancer Centre, Royal Prince Alfred Hospital, NSW; support tool. Many reported that they had ‡Associate Professor, School of Public Health, sought corroboration of Internet informaUniversity of Sydney, NSW. tion with information from other sources, [email protected] especially their doctor. Problems identified TO THE EDITOR: The possible impact of with the Internet were its impersonal the Internet revolution has been much nature, time costs, overabundance of infordiscussed.1-3 In two surveys, conducted in mation, and concerns about the discovery 1999 and 2001, we surveyed oncology of inappropriate, inaccurate or distressing patients from two teaching hospitals in information. Most respondents emphasised central Sydney to explore the experience that they were able to recognise these and impact of Internet use among Austral- limitations, but, notwithstanding, considered the Internet a valuable resource. For ian oncology patients. In November 1999, a questionnaire was example, one respondent wrote: “I felt my mailed to 240 eligible patients selected from capacity to cope with the illness and 617 sequential registrations to the oncology treatment greatly improved because I units. Eligible patients were those who were learned enough from the Internet to alive, competent, had cancer, were of challenge my oncologist and thereby learn known address and whose attending medi- to trust him and his advice.” Despite concerns expressed by many cal officer was participating. In the second survey, to obtain a more doctors, these oncology patients assessed representative sample, we invited all oncol- impacts as either positive or neutral in ogy patients visiting the outpatient clinics overall influence. Increasing Internet use by over a three-month period (September to patients and their families should not be viewed as a problem, but as an opportunity December 2001) to participate. We received completed questionnaires for patients and their treatment teams to from 142 patients (response rate, 59%) in work together, ensuring that patients have 1999 and from 153 patients (number of up-to-date information about their illness refusals unknown) in 2001. Of these, 33% and its treatment and are aware that they (47/142) in 1999 and 46% (70/153) in are not alone in the fight against cancer. 2001 had accessed the Internet for informa1. Van Der Weyden MB, Armstrong RM, Chew M. The tion relating to their illness, either personcommunication revolution: winners and losers [editorial]. Med J Aust 1999; 171: 512. ally or through family and friends. In both surveys, most users accessed the Internet 2. Coiera E. The Internet’s challenge to health care provision [editorial]. BMJ 1996; 312: 3-4. from home, the information sought was 3. Ferguson T. From patients to end users [editorial]. BMJ 2002; 324: 555-556. ❏ mainly in relation to treatment, and the †

Rising cannabis use in Indigenous communities Alan R Clough,* Sheree J Cairney,† Paul Maruff,‡ Robert M Parker§ *Senior Research Officer, Menzies School of Health Research and Northern Territory University, PO Box 1479, Nhulunbuy, NT 0881; †PhD student, ‡Associate Professor, School of Psychological Sciences, La Trobe University, Melbourne, VIC; §Lecturer in Psychiatry, NT Clinical School, Flinders University, Darwin, NT [email protected]

TO THE EDITOR: We write to alert policy makers and clinicians to the challenge presented by rising cannabis use in northeast Arnhem Land, in the Northern Territory, given that many current cannabis users were previously petrol sniffers. In the past five years, there has been a rise in cannabis use and evidence of expansion of supply links in the Miwatj region.1 There are concerns that rising cannabis use is associated with social effects: increased family violence, drug–alcohol psychosis, self-harm and suicide, and community disruption. Policy makers seeking to foster

Current cannabis users among people aged 13–34 years in northeast Arnhem Land Males (n = 145) 100% 80% 60% 40% 20% 0

13-16

17-19

20-24

25-29

30-34

20-24 Age

25-29

30-34

Females (n = 141) 100% 80%

Perceived influence of Internet-acquired information among oncology patients in 1999 and 2001 Better

No change

Worse

Question not answered

12 (26%)

30 (64%)

0

5 (11%)

Discussions with doctor

20 (43%)

22 (47%)

0

5 (11%)

Treatment decisions

22 (47%)

19 (40%)

1 (2%)

5 (11%)

Coping with illness

26 (55%)

15 (32%)

1 (2%)

5 (11%)

Relationship with doctor

24 (34%)

34 (49%)

2 (3%)

10 (14%)

Discussions with doctor

42 (60%)

18 (26%)

1 (1%)

9 (13%)

Treatment decisions

37 (53%)

25 (36%)

0

8 (11%)

Coping with illness

32 (46%)

31 (44%)

1 (1%)

6 (9%)

2001 survey (n = 70)

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40% 20% 0

1999 survey (n = 47) Relationship with doctor

60%

13-16

17-19

Cannabis users with a history of petrol sniffing Cannabis users with no petrol sniffing history Never used cannabis

7 October 2002

Results for samples from two remote communities in the Miwatj region, assessed by using health worker consensus classification, self-report data, and supporting data from health clinic chart review.

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LETTERS

initiatives to minimise harmful outcomes must develop general policies that can have local effects in a varied Northern Territory population. NT police have targeted cannabis in remote communities. A Substance Abuse Select Committee and Illicit Drugs Task Force, each with Indigenous representation, will report to the NT government during 2002. We recently began collecting baseline data to allow us to evaluate the effects on patterns of use of cannabis (and related harm) of community-wide interventions. These interventions will be similar to those implemented for petrol sniffing,2 but with a focus on improved availability of appropriate drug education. We have selected a random sample of about a third of the

Corrections Re “Thiazolidinediones and type 2 diabetes: new drugs for an old disease”, the New Drugs, Old Drugs article by Trisha M O’Moore-Sullivan and Johannes B Prins in the 15 April issue of the Journal (Med J Aust 2002; 176: 381386), in which an editing error resulted in the word “tryglyceride” replacing “total cholesterol”. Thus, on page 383, under the subheading “Both drugs increase HDL and LDL and decrease FFA levels; pioglitazone lowers triglyceride levels”, the first sentence in the second dot point should read “Rosiglitazone also tends to increase total cholesterol level and studies have reported variable effects on ratios of total cholesterol to high-density lipoprotein (HDL) and of LDL to HDL.” ❏ Re the article “The contribution of airway structure to early childhood asthma”, by McKay KO and Hogg JC, in the 16 September supplement to the Journal, Early childhood asthma: what we know and what we need to know (Med J Aust 2002; 177: S45-S47). The last two lines of the figure caption on page S46 were omitted. The full caption should read: “The vessels in the submucosa (a) are smaller than the vessels in the adventitia (c), and the vessels that pass through the muscle layer (b) connect them. These two sets of vessels are perfused in series, providing a basis for a difference in the nature of the inflammatory reaction in the submucosa and lumen compared with the peribronchiolar space.” The article, with correct caption, appears on our website. ❏

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residents (aged 13–34 years) from two communities. From this sample, current cannabis users (at least weekly) and past petrol sniffers have been identified by using health worker consensus classification, supported by data from review of the health clinic chart and self-report, if available. These data for 145 males and 141 females are presented in the Figure. Among males aged 20–34 years, 74% are current cannabis users and, of these, 60% are former petrol sniffers. To date, 57 cannabis users have agreed to interview (34 males and 23 females) and, of these, 38 met DSM-IV criteria for cannabis dependence.3 A particular health concern is that persistent cannabis use may compound any residual cognitive impairment from petrol sniffing. Competing interests: None identified. Acknowledgements: This research is funded by the National Health and Medical Research Council through support from the National Illicit Drugs Strategy and the Commonwealth Department of Health and Ageing. The study has ethical approval from the Human Research Ethics Committee of the NT Department of Health and Community Services and the Menzies School of Health Research. 1. Clough AR, Guyula T, Yunupingu M, Burns CB. Diversity of substance use in eastern Arnhem Land (Australia): patterns and recent changes. Drug Alcohol Rev. In press, 2002. 2. Burns CB, Currie BJ, Clough A, Wuridjal R. Evaluation of strategies used by a remote Aboriginal community to eliminate petrol sniffing. Med J Aust 1995; 163: 82-86. 3. American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4th ed. Washington, DC: American Psychiatric Press, 1994. ❏

Hepatitis C virus seroconverters: help wanted Katrein Depraetere,* Shelley J Toepfer,† Joy G Copland,‡ Matthew D Gaughwin,§ David R Shaw,¶ Russell G Waddell** *Medical Officer, STD Services; †Nurse Counsellor, Drug and Alcohol Resource Unit; ‡Senior Project Officer, STD Services; §Director, Drug and Alcohol Resource Unit, Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000; ¶Director, Infectious Diseases Unit; **Clinical Manager, STD Services, Royal Adelaide Hospital, Adelaide, SA. [email protected]

TO THE EDITOR: In Australia, an estimated 11 000 people become infected with hepatitis C virus (HCV) each year.1 Most are injecting drug users. The Early Hepatitis C Intervention Project was a collaboration between the STD Services Surveillance Unit, Drug and Alcohol Resource Unit and Infectious Diseases Unit at the Royal Adelaide Hospital, Adelaide, South Australia. Its objectives were to manage people who had seroconverted in the preceding 12 months and to provide standard treatments for drug use and dependence. Services included information and education on HCV, refer-

ral, counselling, psychosocial support and three-monthly clinical evaluation. The project was approved by the Ethics Committee of the Royal Adelaide Hospital and funded by the Department of Human Services for 18 months. The attendance rate was low. Of 88 people with HCV seroconversion who were identified as eligible for enrolment by the Surveillance Unit (from the mandatory notification scheme), 57 agreed to further contact by mail or telephone, and 12 attended for risk assessment. Of these, eight enrolled in the project (10% of those eligible). Despite demographic variation within the group, similarities included difficulties with accommodation, finances, mental health and social integration. Seven of the eight participants had injecting drug use as the risk factor for HCV infection. Most participants also used alcohol and cannabis. During the program, half decreased their risk-taking behaviour: four reduced injecting drug use, and four reduced alcohol use, reaching low risk levels. Characteristics of participants at their last interview are summarised in the Box. Two participants are maintaining regular contact with the Drug and Alcohol Resource Unit. Despite encouragement, few of the target group engaged in the program. We do not know why so few people who agreed to attend a first appointment failed to do so. We did not have their permission or the resources to contact them again. Maintaining contact with participants also proved challenging, and was in part unsuccessful because of complex, multifaceted social issues aside from HCV infection (Box). These included unstable accommodation, use of health services only when in crisis, mental health problems, financial difficulties, polydrug use and continued risktaking behaviours despite harm-reduction information. In conclusion, the Australian epidemic of HCV infection, driven by injecting drug use, is likely to continue unless a new approach to harm minimisation is developed. Such an approach will recognise that comorbidities and social dislocation influence risk of infection. Unless treatment programs address coexisting problems, it will be futile to offer definitive treatment for HCV infection.2 Within the limited objectives and resources of this project, we were unable to support these people comprehensively. We believe that a “one-stop shop” that includes active and intensive case management by a flexible, multidisciplinary team and deals with social, economic and mental health

MJA

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7 October 2002

LETTERS

Characteristics of participants in the Early Hepatitis C Intervention Project at last interview

Age, sex

Place Current of mental Employ- Polydrug residence illness* ment use

Attendances At 5 nominated appointments Total†

IDU change‡

Persistent viraemia‡ Yes

rate ratios found by Johnston et al may not alter appreciably. However, it would have been useful for the investigators to have at least discussed any effects that controlling for serial correlation and other potential confounders might have had on their findings.

19, F

No

Yes

NFA

Yes

3

6

Reduced IDU

21, F

Part-time

Yes

NFA

Yes

3

5

Reduced IDU

No

21, M

No

Yes

NFA

Yes

3

4

No IDU at enrolment

Yes

1. Johnston FH, Kavanagh AM, Bowman DMJS, Scott RK. Exposure to bushfire smoke and asthma: an ecological study. Med J Aust 2002; 176: 535-538.

24, M

Voluntary

No

Rental

Yes

1

1

Denied IDU ever

Yes

2. Kunzli N, Kaiser R, Medina S, et al. Public-health impact of outdoor and traffic-related air pollution: a European assessment. Lancet 2000; 356: 795-801.

30, M

Casual

Yes

NFA

No

2

4

No IDU

Yes

36, M

No

Yes

Parents

Yes

1

4

Unknown

Yes

38, M

Full-time

Yes

NFA

Yes

2

3

Reduced IDU

No

43, M

Full-time

No

Rental

Unknown

1

1

Unknown

No

IDU=injecting drug use. NFA=no fixed abode. *Mainly depression, anxiety and personality disorder. †Includes self-initiated visits. ‡Determined by polymerase chain reaction.

issues may be a more effective approach to the care of people with recent HCV infection. 1. Commonwealth Department of Health and Aged Care. National Hepatitis C Strategy 1999-2000 to 2003-2004. Canberra: The Department, 2000. 2. Jaeckel E, Cornberg M, Wedemeyer H, et al. Treatment of acute hepatitis C with interferon alfa-2b. N Engl J Med 2001; 345: 1495-1497. ❏

Serial correlation and confounders in time-series air pollution studies Bin B Jalaludin,* Guy B Marks,† Geoffrey G Morgan‡ *Deputy Director, Epidemiology Unit, †Respiratory Physician, Liverpool Hospital, Locked Mail Bag 7017, Liverpool BC, NSW 1871; ‡Epidemiologist, Southern Cross Institute of Health Research, Lismore, NSW. [email protected]

TO THE EDITOR: The recent article by Johnston et al is an important contribution to the small but growing body of literature on the health effects of particulate matter (PM) pollution derived from bush or forest fire.1 The authors studied an important wood smoke PM exposure in Australia and

showed consistent associations between higher concentrations of PM and emergency department presentations for asthma. Most research on the effects of PM has focused on motor-vehicle-derived PM pollution.2,3 However, Johnston et al do not appear to have accounted for serial correlation in their data. Measurements connected in time, such as repeated measurements of the same population, are likely to be correlated and not independent.4 Further, school holidays have been shown to influence hospital admission rates.5 The major Northern Territory school holidays in June and July are in the middle of the study period. Johnston et al adjusted for some important confounders in their analysis (acute respiratory infections and weekdays/weekends).1 However, in time-series data, especially those dealing with asthma, serial correlation, as well as other potentially important confounders such as school holidays and temperature and humidity, should also be assessed. It may be that, even after appropriate adjustments for serial correlation and potential confounders, the

Rate ratio for asthma presentations (95% CI) 0), the effective sample size is reduced and the associated CIs are inevitably wider. For any given ICC greater than zero, larger cluster sizes also further reduce the effective sample size. Applying appropriate formulas,3 we calculated effective sample sizes for risk factors in the ASAP

Effective sample size, assuming three different magnitudes of intracluster correlation (ICC) Actual n

Effective n if ICC = 0.015



Hypertension

14 280

8643

4499

2670

Hypercholesterolaemia

12 516

7973

4317

2608

Smoking

14 297

8649

4500

2670

Diabetes

13 767

8455

4449

2653

Atrial fibrillation

14 194

8611

4490

2667

Stroke/transient ischaemic attacks

14 321

8657

4502

2671

Risk factor Total

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7 October 2002

LETTERS

study, assuming three different magnitudes of ICCs, ranging from relatively modest (0.015) through more substantive (0.1) (see Box). Given the large denominator of the ASAP study, our methodological concern may be only minor in terms of the width of the CIs reported, but the reader is unable to judge whether or not this is the case, as no ICCs were reported. As sample-size calculations for future interventional studies would be informed by publication of ICCs,4 we encourage such reporting in future. Third, we believe the authors’ quantitative findings would have been most useful if they had been age-adjusted in line with Australian community norms. 1. Sturm JW, Davis M, O’Sullivan JG, et al. The Avoid Stroke as Soon as Possible (ASAP) general practice stroke audit. Med J Aust 2002; 176: 312-316. 2. Campbell MK, Mollison J, Steen N, et al. Analysis of cluster randomized trials in primary care: a practical approach. Fam Pract 2000; 17: 192-196. 3. Donner A, Klar N. Design and analysis of cluster randomisation trials in health research. London: Arnold, 2000. 4. Campbell M, Grimshaw J, Steen N. Sample size calculations for cluster randomised trials. J Health Serv Res Policy 2000; 5: 12-16. ❏

Jonathan W Sturm,* Stephen M Davis,† John G O’Sullivan,‡ Miriam E Vedadhaghi,§ Geoffrey A Donnan¶ *Research Fellow; ¶Director, National Stroke Research Institute and Department of Neurology, Austin and Repatriation Medical Centre, Heidelberg West, VIC; †Director of Neurology, Department of Medicine, Melbourne University, and Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC; ‡Associate, Blackburn Clinic, Blackburn, VIC; §Project Associate, Servier Laboratories, Hawthorn, VIC. [email protected]

IN REPLY: We thank Middleton et al for their interest in our article. As 96% of questionnaires in our ASAP study1 were completed by September 2000, their study (as yet unpublished) and ours were not concurrent. Statistically, based on the information given by Middleton et al, we would expect 5.5 GPs (296 x 333/18066) to

Intracluster correlations (ICCs) for stroke risk factors in the ASAP stroke audit1* Risk factor

All

Men

Women

Current smoker

0.07

0.09

0.08

Hypercholesterolaemia

0.06

0.06

0.07

Hypertension

0.06

0.05

0.07

Diabetes

0.04

0.05

0.07

Past TIA/stroke

0.018

0.024

0.013

Atrial fibrillation

0.016

0.017

0.023

TIA = transient ischaemic attack. *Calculated using the analysis of variance (ANOVA) method.2

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7 October 2002

be involved in both studies. Chance, or because direct involvement in the ASAP study had finished months earlier, may explain why none of the doctors in the survey by Middleton et al stated that they were involved in a stroke audit. In answer to the claim that “no GP data by State and Territory” were provided, we did in fact indicate in our article how many GPs from each State and Territory participated. Intracluster correlations (ICCs)2 for each risk factor in our study are shown in the Box. ICCs have a greater effect on sample size than on CIs, because CI width is inversely proportional to the square root of the sample size. The large sample size of ASAP means that the study has acceptable precision, even after allowing for ICCs. Overall estimates for risk factors were provided for the population of people consulting GPs, which is the relevant population. We would not necessarily expect the same distribution of risk factors in people not attending GPs. Age- and sexspecific risk-factor prevalences, shown in Box 3 of our article,1 can be used to calculate age- and sex-standardised rates for any desired population. We are confident that the information obtained in our study is likely to be representative of most Australian general practice environments. 1. Sturm JW, Davis M, O’Sullivan JG, et al. The Avoid Stroke as Soon as Possible (ASAP) general practice stroke audit. Med J Aust 2002; 176: 312-316. 2. Ridout MS, Demetrio CBG, Firth D. Estimating intraclass correlation for binary data. Biometrics 1999; 55: 137148. ❏

Itching bites may limit Ross River virus infection Alan E Dugdale Honorary Principal Research Fellow, Department of Paediatrics and Child Health, University of Queensland Medical School, Herston, QLD 4006 [email protected]

TO THE EDITOR: Reactions to insect bites are unpleasant and can be dangerous.1 Kumar2 commented that people who react to mosquito bites with local itching and inflammation appeared less likely to develop malaria than those with no reaction. In a later personal communication, he gave me unpublished data showing an inverse linear relationship between the severity of the reaction to mosquito bites and the incidence of clinical malaria. Ross River virus infection is endemic in all Australian states. A specific serological test is available to confirm suspicious clinical illnesses. Some people have serolog-

Reactions to mosquito bites among people with and without evidence of Ross River virus (RRV) disease Moderate to No reaction severe reaction Past RRV disease

7

0

No past RRV disease

0

18

ical signs of past infection without any history of clinical disease. With Kumar’s findings in mind, I asked people with a past history of clinical Ross River virus infection, proven by serology, whether they reacted to mosquito bites. All seven asked said that they had had no reaction. Their main complaint was the noise made by predatory mosquitoes. I then asked patients who were in the same age range and general social class, who lived in the same area and were attending clinics with other diseases, whether they had had any clinical illness diagnosed as Ross River virus infection. Of the 18 asked, none had had the clinical disease or serological tests for the disease. All 18 had moderate to severe reactions and itching with mosquito bites. The Box shows these results Fisher’s exact test gives the probability of this finding as 0.0000003. These observations have not explored all aspects of the problem, so this level of probability may be optimistic, but, even so, it makes pointless any further informal collection of data. These findings justify a formal epidemiological study, including antibody titres. It should include those who react to mosquito bites and those who do not, and those with and without a past history of the clinical illness. This informal study suggests that reactions to mosquito bites protect against Ross River virus infection, and parallels Kumar’s findings in malaria. There may be behavioural and biological explanations for this finding. People who itch with mosquito bites may take greater precautions to avoid them. Conversely, people who do not itch may spend more time outdoors and be more likely to be bitten. Biologically, reactions to bites may be examples of a generalised protective effect of local reactions against insect-borne diseases. The inflammatory reaction with itching may be a factor in defence against infection3 by limiting or destroying injected parasites and viruses locally or through a more vigorous generalised response that prevents disease or limits infection to a subclinical level. Investigation of local inflammatory response might provide clues to effective prevention and treatment.

399

LETTERS

1. O’Hehir RE, Douglass JA. Stinging insect allergy. Med J Aust 1999; 171: 649-650. 2. Kumar A. Itching and immunity [letter]. Lancet 1996; 348: 1383. 3. Fang D, Elly C, Gao B, et al. Dysregulation of T lymphocyte function in itch mice: a role for Itch in TH2 differentiation. Nat Immunol 2002; 3: 281-287. ❏

You oughta be congratulated? Alex A Padiglione,* Catherine E Marshall,† Tony M Korman‡ *Infectious Diseases Physician, † Registrar, ‡Director, Department of Infectious Diseases, Monash Medical Centre, Clayton, VIC 3168. [email protected]

TO THE EDITOR: We write to express our concern at the publication of the recent supplement “Essential role of fats throughout the lifecycle”, adorned by the sponsor’s logo.1 It was an interesting counterpoint to an accompanying article in the main journal regarding the need for industry–academia collaborations to “strike a balance”.2 While the issue of relationships between industry and doctors is complex, and few of us are truly independent, the publication of such a branded document is disquieting. Directed sponsorship, beyond mere advertising, undermines the credibility of such supplements and the Journal itself, regardless of the authors’ expertise, objectivity and the importance of the topic. Unfortunately, we are left with the taste that this is a spread designed to butter us up. 1. Gibson RA, editor. Essential role of fats throughout the lifecycle. Med J Aust 2002;176 (Suppl 3 June): S105-S124. 2. Moses H, Perumpanani A, Nicholson J. Collaborating with industry: choices for Australian medicine and universities. Med J Aust 2002; 176: 543-546. ❏

Martin B Van Der Weyden Editor, The Medical Journal of Australia, Locked Bag 3030, Strawberry Hills, NSW 2012. [email protected]

IN REPLY: “Oh what a feeling” to receive a congratulatory letter! But the euphoria was short lived, as, on closer inspection, congratulations turned to castigation. The offending event was the Journal’s publication of an industry-supported supplement,1 and its practice of branding supplements with the logos of their sponsoring bodies. Although sponsorship by government agencies or non-profit health organisations rarely provokes comment, industry sponsorship is another matter. As industry support for research and other healthrelated activities will inevitably increase in the future, we at the Journal are pleased that Padiglione and colleagues have aired their anxiety. Irrespective of the source of sponsorship, the Journal’s policy governing the publica-

400

tion of supplements follows the recommendations of the International Committee of Medical Journal Editors.2 These include that: ■ the journal’s editor must take full responsibility for policies, practices and content of supplements, must approve the appointment of the editors of supplements, and must retain the authority to reject articles; and ■ the source of funding should be clearly stated and prominently located in supplements, preferably on each page. To these principles the Journal has added its own requirements.3 These include the need for peer review and that editors of and contributors to supplements declare competing interests and compensations. These were clearly identified on the title page of the offending publication.1 For our readers, the Journal is the bread and its supplements the butter. One can always refuse to taste the butter. But, for those who hanker after a little fat, we aim to ensure, through churning by external peer review and transparent sponsorship of the product, that “butter is better”. 1. Gibson RA, editor. Essential role of fats throughout the lifecycle. Med J Aust 2002; 176 (Suppl 3 June): S105S124. 2. International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals and separate statements (accessed 9 September 2002). 3. MJA policy on sponsored supplements (accessed 11 September 2002). ❏

Correspondents Please see mja.com.au/public/ information/instruc.html for submission details.

The Medical Journal MJ A of Australia

Editor Martin Van Der Weyden, MD, FRACP, FRCPA Deputy Editors Bronwyn Gaut, MBBS, DCH, DA Ruth Armstrong, BMed Mabel Chew, MBBS(Hons), FRACGP, FAChPM Kincaid-Smith Editorial Fellow Jenny Bergen, MBBS, FRANZCP Manager, Communications Development Craig Bingham, BA(Hons), DipEd Senior Assistant Editor Helen Randall, BSc, DipOT Assistant Editors Elsina Meyer, BSc Kerrie Lawson, BSc(Hons), PhD, MASM Tim Badgery-Parker, BSc(Hons) Josephine Wall, BA, BAppSci, GradDipLib Proof Reader Richard Bellamy Editorial Administrator Kerrie Harding Editorial Assistant Christine Tsim Production Manager Glenn Carter Editorial Production Assistant Melissa Sherman Librarian, Book Review Editor Joanne Elliot, BA, GradDipLib Consultant Biostatistician Val Gebski, BA, MStat

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