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Medical practices

Emergency medicine Letters 20 January 2014 Free

Changing trends in venous thromboembolism-related imaging in Western Australian teaching hospitals, 2002–2010

In reply: We thank Mountain for his comments. As he points out, it is only possible to infer cause and effect from observational data. The fact that referrals for D-dimer levels and computed tomography pulmonary angiography increased during the same period does not prove that one “drove” the other, although we believe this is a reasonable inference. Importantly, D-dimer testing was introduced as a “rule-out” ...

William B G Macdonald · Tatiana Segard

13 11245

Vitamin B12 and folate tests: the ongoing need to determine appropriate use and public funding

It’s not as simple as new for old: we need to follow a process for “disinvestment” in existing medical procedures, services and technologies Criteria have been developed for assessing the safety, effectiveness and cost-effectiveness of new and emerging health interventions, but additional challenges exist in identifying opportunities for reducing the use of existing health technologies or procedures that are potentially overused, (cost-)ineffective or unsafe.1 Criteria have been proposed to flag technologies that might warrant further investigation under quality improvement programs.1 These criteria are: new evidence becomes available; there is geographical variation in use; variation in care between providers is present; the technology has evolved and differs markedly from the original; there exists a temporal trend in the volume of use; public interest or controversy is present; consultation with health care workers and funders raises concerns; new technology has displaced old technology; there is evidence of leakage (use beyond the restriction or indication); the technology or intervention is a “legacy item” that has never been assessed for cost-effectiveness; use is not in accordance with clinical guidelines; or the technology is nominated by clinical groups. After such a nomination was made by members of the clinical laboratory community regarding vitamin B12 and folate tests, we sought to determine whether these tests met other criteria. We hope that this article will encourage debate and discussion about the appropriate use of these tests. Testing for vitamin B12 and folate deficiencyDiagnosing vitamin B12 and folate deficiencies is difficult. The symptoms are diverse (such as malaise, fatigue and neurological symptoms), as are the signs (including megaloblastic anaemia and cognitive impairments). Defining target conditions is, therefore, also difficult. Tests include a full blood count and blood film examination, serum B12, serum folate and red-cell folate (RCF) assays, as well as examination of metabolic markers such as methylmalonic acid (MMA) and homocysteine (Hcy). Untreated vitamin B12 deficiencies may cause serious health problems, including permanent neurological damage (which may occur with low serum B12 levels without haematological changes). Maternal folate deficiencies have been associated with neural tube defects in infants. Potential vitamin B12 or folate deficiencies therefore need to be appropriately investigated and managed. New evidenceThe utility of a diagnostic test is influenced in part by its precision (the ability of a test to faithfully reproduce its own result) and its diagnostic accuracy (ability to discriminate between a patient with a target condition and a healthy patient). Evidence suggests serum B12 tests have poor discriminative ability in many situations, and debate is ongoing over which folate assay is most useful. The only systematic review and meta-analysis of the diagnostic accuracy of serum B12 tests (conducted by members of our group) suggested that these tests often misclassify individuals as either B12 deficient or B12 replete.2 These findings are consistent with other reports in the literature. One recent report states: Both false negative and false positive values are common (occurring in up to 50% of tests) with the use of the laboratory-reported lower limit of the normal range as a cutoff point for deficiency.3 And further: There is often poor agreement when samples are assayed by different laboratories or with the use of different methods.3 Widespread CBLA (competitive-binding luminescence assay) malfunction has also been noted, with assay failure rates of 22% to 35%4 (interference due to intrinsic factor antibodies may explain some of this variation). While a critical overview has suggested that “falsely normal cobalamin concentrations are infrequent in patients with clinically expressed deficiency”, the author notes challenges in diagnosing subclinical deficiency5 (mild metabolic abnormalities without clinical signs or symptoms). Assessment of this evidence base is complicated by the lack of a universally accepted gold standard and by target conditions that are difficult to define, variable clinical presentations and variable cut-off values used to define deficiency. For investigating folate status, RCF assays are thought to be less susceptible to short-term dietary intake than are assays for serum folate. However, it has been reported that: The red cell folate assay is more complex to perform than the serum folate assay and requires more steps in sample handling before analysis, and this may be one of the reasons why the precision of the red cell folate assay is less than that of the serum folate assay.6 As discussion continues over which folate test is preferable, new evidence related to the prevalence of folate deficiencies in countries with mandatory food fortification has shifted the focus toward whether there is a need to perform any folate investigations in these jurisdictions. In Australia, mandatory fortification of wheat flour with folic acid was introduced in September 2009.7 Prevalence estimates from a sample of inpatients and outpatients suggested that folate deficiency stood at 0.5% in April 2010, showing an 85% reduction in absolute numbers since April 2009.7 While there is currently no evidence to suggest that the prevalence of megaloblastic anaemia caused by folate deficiency has been reduced, the low frequency of low serum RCF test results in countries where there is mandatory fortification of grain products with folic acid supports the perspective that “there is no longer any justification in ordering folate assays to evaluate the folate status of the patients”.8 Technology developmentOver time, multiple technologies for analysing vitamin B12 status have become available, including assays for measuring holotranscobalamin (holoTC, the bioavailable form of vitamin B12), as well as metabolic markers such as MMA and Hcy.3,5 However, like all tests, these are imperfect: holoTC is expensive, not routinely available, itself reliant on poorly defined serum B12 reference ranges, and is yet to be confirmed as a superior test to the serum B12 assay.5 Hcy measurement is subject to artefactual increases due to collection practices, and reference ranges are variable. The availability of MMA tests is restricted to some clinical and research laboratories. As a result, the optimal procedure for measuring vitamin B12 is unclear. As noted above, while a number of approaches exist for assessing folate status, there is currently no consensus on the most appropriate laboratory investigation process. Temporal, geographical and provider variationsAustralian Medicare utilisation data have shown substantial growth in the use of item 66602, which relates to the combined use of serum B12 and folate tests. Between the financial years 2000–01 and 2009–10, use increased from 1082 services per 100 000 population to 7243 services per 100 000 population (21.78% average annual growth rate).9 Over the same period, spending on pathology services overall grew at an average annual rate of 6.3%. Geographical variation was also present, with the number of services reimbursed for item 66602 ranging from 1962 per 100 000 population in the Northern Territory to 8658 per 100 000 population in the Australian Capital Territory in 2009–10.9 While some of this variation may be due to demographic differences and populations known to have access to fewer health services (eg, Indigenous Australians), the substantial temporal and geographical differences in use raise more questions about appropriate use of these tests, and whether or not they are underused or overused. GuidelinesGuidelines related to the use of vitamin B12 and folate tests vary widely in their recommendations. While some recommend B12 and folate tests as screening tools in commonly encountered illnesses such as dementia, others suggest restricting testing to patients who have already undergone pretest investigations (such as full blood examinations; however, we note that neurological damage may occur in patients with low serum B12 levels and without haematological changes).10,11 Guidelines may differ on key recommendations, such as the preferred first-line investigation for establishing folate status, while some question the utility of folate investigations at all in jurisdictions where food is fortified with folate.12-14 LeakageWith wide variability in guideline recommendations, and with few appearing to consider the diagnostic accuracy of B12 or folate tests, determining the extent to which services have “leaked” beyond their clinical indications is difficult. Possible leakage is evidenced by the use of serum B12 tests among patients presenting with weakness and tiredness, which is not supported by any available guidelines.15 A large study of general practitioners indicated that between April 2000 – March 2002 and April 2006 – March 2008 their use of serum B12 tests among patients presenting with weakness and tiredness increased by 105%.15 DiscussionTests for investigating patients’ vitamin B12 and folate status have become widely used in clinical practice. Yet existing evidence suggests that the diagnostic accuracy of serum B12 tests is difficult to determine and may be highly variable. While other tests are available for investigating suspected B12 and folate deficiency (such as holoTC, MMA and Hcy), the diagnostic accuracy of these tests is also contested. Challenges in examining the diagnostic accuracy of serum B12 tests include highly variable clinical presentations, lack of a gold standard and inconsistent cut-off values used to define deficiency. While it remains under debate whether the serum or red-cell folate test is most useful for investigating folate status, mandatory folate fortification in Australia may call into question any use of these tests. Temporal variation in use and geographical differences in how these tests are employed are both evident in Australian data. Moreover, available clinical guidelines are highly inconsistent in their recommendations. Collectively, the issues of test accuracy, wide variability in test use, and inconsistent guideline recommendations suggest that the use of vitamin B12 and folate tests is an area with much scope for quality improvement. To improve the use of these tests, further assessment is needed that examines the complexity associated with clinical decision making and the various factors influencing why doctors request these tests. The decision to request an investigation such as a B12 or folate test may be driven by a range of factors, including ease of use, cost, absence of significant patient risk, the perceived need to respond to patient requests, lack of appreciation of the diagnostic accuracy of the tests, or ready availability of results.16 Understanding how these factors influence the use of B12 and folate tests may best be achieved through direct consultation with general practitioners, pathologists, specialists and consumers and is a critical step in advancing the assessment of these tests.

Cameron D Willis PhD · Michael P Metz MD · Janet E Hiller MPH, PhD · Adam G Elshaug MPH, PhD

12 11328

Over 150 potentially low-value health care practices: an Australian study

To the Editor: We read the recent study by Elshaug and colleagues1 with interest, but were concerned by the inclusion of radiotherapy for spinal cord disease as a potentially low-value intervention. The lack of clinical review in the identification process appears to be the key driver in coming to this erroneous conclusion. Elshaug and colleagues recognise the need for clinical expertise in assessing trials demonstrating no ...

Andrej Bece · Christopher Hamilton · Brigid E Hickey

10080

Over 150 potentially low-value health care practices: an Australian study

To the Editor: Elshaug and colleagues recently attempted to identify low-value health care practices.1 They further identified 13 services found by more than one of their search methods, implying that these services may be of particularly low value. One such practice identified is “radiotherapy for patients with metastatic spinal cord disease”.1 However, this terminology is loose at best, and the following quotes from Elshaug et al’s own ...

Graham Pitson

10085

Over 150 potentially low-value health care practices: an Australian study

In reply: I thank Bece and colleagues and Pitson for engaging constructively with this quality improvement agenda. Bece et al challenge the inclusion of radiotherapy for spinal cord disease in our list of 150 candidate treatments potentially warranting further review under a quality improvement program.1 Pitson calls attention to “loose terminology” in the same example. This latter point, I concede. Precision of language in relation to ...

Adam G Elshaug

13 10473

Injuries to the head and face sustained while surfboard riding

To the Editor: Surfboard riding is an iconic pastime in Australia. Injuries to the head and face constitute a considerable proportion of surfing injuries;1-5 26% of acute surfing injuries are to the head and face, and these make up 42% of emergency department presentations by surfers.3 We conducted a retrospective review at our tertiary referral hospital of patients who underwent medical imaging for injuries sustained to ...

Simon J Dimmick · Patrick V Sheehan · Mark Gillett · Suzanne E Anderson

Ageing Letters 15 October 2012 Free

Vitamin B12 screening in older inpatients without known risk factors: why do clinicians measure it?

Tests for serum vitamin B12 and red cell folate levels are commonly requested in elderly inpatients to rule out reversible causes of cognitive impairment (eg, delirium). This imposes some cost on the community. The evidence for the association of cognitive impairment and vitamin B12 deficiency is inconclusive. It is also unclear whether other markers, such as elevated mean corpuscular volume (MCV) and ...

Celia S M Ting · John C Oldroyd · Michele R Levinson

Endocrinology Clinical focus 20 August 2012 Free

Australian Diabetes Foot Network: management of diabetes-related foot ulceration — a clinical update

Appropriate assessment and management of diabetes-related foot ulcers (DRFUs) is essential to reduce amputation risk. Management requires debridement, wound dressing, pressure off-loading, good glycaemic control and potentially antibiotic therapy and vascular intervention. As a minimum, all DRFUs should be managed by a doctor and a podiatrist and/or wound care nurse. Health professionals unable to provide appropriate care for people with DRFUs should ...

Shan M Bergin BAppSci(Pod), PhD · Joel M Gurr BSc(Pod), MBA · Bernard P Allard MB BS, FRACS(Vasc) · Emma L Holland RN, CDE, MA(Ed) · Mark W Horsley MB BS, FRACS(Ortho) · Maarten C Kamp FRACP, MHA, GAICD · Peter A Lazzarini BAppSci(Pod) · Vanessa L Nube DipAppSci(Pod), MSc(Med) · Ashim K Sinha MB BS, MD, FRACP · Jason T Warnock DipAppSc(Chir), GradCertDiabEd · Jan B Alford RN, MEd(AdEd), CDE · Paul R Wraight MB BS, FRACP, PhD

Medical practices Clinical focus 16 July 2012 Free

Justifying referrals for paediatric CT

An adolescent female patient presents with acute lower back pain of recent onset and no history of trauma. Is it warranted to order a computed tomography (CT) scan of her lumbar spine? The justification for a CT scan at the individual level is complex and the risk–benefit ratio must be considered; the risks associated with radiation are often not well understood and, similarly, the benefit for an individual may be difficult to determine.

Zoe Brady BSc(Hons) · Timothy M Cain MB BS, FRANZCR, MBA · Peter N Johnston BSc(Hons), PhD

Cardiovascular diseases Case reports 7 May 2012 Free

Brain abscess due to Propionibacterium propionicum in Eisenmenger syndrome

Clinical record A 33-year-old man with Eisenmenger syndrome due to a congenital ventricular septal defect presented with a 3-week history of headache, blurred vision and expressive dysphasia, and unintentional weight loss of 10% of his body weight. His medications included sitaxsentan sodium (a sulfonamide endothelin-receptor antagonist, recently withdrawn because of hepatotoxicity) for pulmonary arterial hypertension. He ...

Anthony M T Chau MB BS(Hons) · Lileane L Xu · Jacob M Fairhall MB BS, FRACS · Joga Chaganti FRANZCR · Brendan J McMullan BMed(Hons), DTMH, DCH

Case20report chau
Hematologic diseases Case reports 16 April 2012 Free

Endovascular therapy after stroke in a patient treated with dabigatran

This is the first report of endovascular therapy for acute ischaemic stroke in a patient with atrial fibrillation who was taking the direct thrombin inhibitor dabigatran for stroke prevention. As more of these agents will ...

Andrew W Moey MB BS · Simon A Koblar MB BS, FRACP, PhD · Steve Chryssidis MB BS, RANZCR · Martin Robinson MB BS, FRACP · Jim Jannes MB BS, FRACP, PhD

Cardiovascular diseases Clinical focus 5 March 2012 Free

Appropriate indications for computed tomography coronary angiography

Despite the various functional tests and biomarkers available for evaluation of patients with coronary artery disease (CAD), we sometimes look for the reassurance of anatomical information by way of a coronary angiogram. However, as an invasive modality, it does carry some risks, and the proportion of patients with normal coronary angiograms has remained relatively stable at 15%. In recent years, the rapid development of computed ...

Gary Y H Liew MB BS, FRACP · Michael P Feneley MD, FRACP · Stephen G Worthley MD, PhD, FRACP

Walter Lowen

Walter Lowen was born in Vienna on 10 March 1916 and spent his childhood in Lwow, Poland. A national junior table tennis champion, Walter contributed to Poland’s bronze medal at the Swaythling Cup world championships in London in 1935. Religious persecution in Europe spurred his migration to Australia in July 1939, a few months before he was due to complete his medical degree at the University of Lwow. In 1940, Walter was accepted into medicine at the University of Melbourne and, in 1941, he married Sima, whom he had met en route to Australia. Walter still pursued table tennis, winning the Australian singles title in 1948 as well as many state singles titles. In 2000, he was inducted into the Table Tennis Victoria Hall of Fame. Walter graduated in 1945 and undertook his residency at Launceston General Hospital. In 1948, he returned to Melbourne, where he practised as a general practitioner in Reservoir and Ashburton. In 1958, he moved to The Alfred Hospital, Melbourne, where he trained in radiology and, in 1961, he gained Fellowship of the Royal Australasian College of Radiologists. He then developed his diagnostic expertise at the Melbourne Radiology Clinic in female infertility, obstetrics, and thoracic and renal radiology. During this time, he published papers on medullary sponge kidney disease, cavitating pulmonary metastases and radionuclide placental localisation. Walter’s obstetric and gynaecological imaging expertise led to his appointment as Director of Radiology at Royal Women’s Hospital, Melbourne, between 1962 and 1975. From 1976 until his retirement in 1994, he continued sessional work at Royal Southern Memorial Hospital, Bairnsdale Regional Hospital and Preston and Northcote Community Hospital. After he retired from medicine, Walter concentrated on his family and competitive bridge. As a Grand Master, he helped Victoria win the open teams event at the Australian National Bridge Championships in 1972. Walter remained intellectually sharp until he died peacefully, aged 94, in Melbourne on 11 January 2011, survived by Sima and their three children Richard, Mark and Norma. Walter was inspirational and generous to many, and is remembered with affection as a gentle giant.

Richard J Lowen · Mark Lowen · Norma Gilbert

Is Australia ready to use glycated haemoglobin for the diagnosis of diabetes?

To the Editor: I would like to add some detail to the article by Shaw and colleagues1 on the costs of screening for diabetes and glycated haemoglobin (HbA1c) testing. At face value, using the 85% Medicare Benefits Schedule (MBS) rebate, the item for HbA1c testing costs $1.85 less than the item for a glucose tolerance test (more than 10% cheaper), but it is a little more complicated than these simple figures suggest. In 2010, 295 023 glucose tolerance tests (item number 66542) were claimed on the MBS — up 61% on the number ordered in 2004 (183 090)2 — which reflects the increase in ordering by general practitioners, who I believe are more aware of the increased incidence and prevalence of one of the most common chronic diseases in Australia. I also believe that it reflects the use of the glucose tolerance test as the definitive test for diabetes (rather than relying on a single fasting glucose level) in private practice. In contrast, 1 021 247 HbA1c tests (item number 66551) were claimed in 2010, versus 911 623 in 2004 — up by only 12% over the same 7-year period.2 This reflects “coning” of pathology items in the MBS. There are two types of cone that affect billing of HbA1c tests: the “grand cone”, which restricts billing to the three most expensive items ordered by a GP on a single occasion (regardless of the number of tests ordered), and the “temporal cone”, where only four HbA1c tests can be billed in any 1 year. The glucose tolerance test has no temporal restrictions and is usually performed on its own, so it avoids the grand cone, but the HbA1c test is often ordered with a bank of other tests (eg, as part of diabetes monitoring) and is thus not usually billed to Medicare. In my practice, only 30% of reported HbA1c tests can be billed to Medicare, hence the cost to Medicare per reportable test is about a third of the listed rebate of $14.40. Furthermore, as Shaw et al point out, HbA1c testing cannot currently be billed for the diagnosis of diabetes, although my personal observation is that many doctors are already using this as a screening test. There are essentially three powerful drivers for HbA1c testing: the increased prevalence of diabetes, the (honest) push to test HbA1c levels every 4 months (through care plans etc) and the use of HbA1c tests to diagnose diabetes. I believe that Medicare currently pays for less than 40% of these tests and that this proportion will fall as more HbA1c tests are requested. The majority of the costs for HbA1c testing are subsidised by pathology practices — which, philosophically, I find quite odd. These points need to be taken into account when undertaking a cost–benefit analysis of screening for diabetes in Australia.

Len D Moaven

General medicine 7 November 2011 Free

Patricia Anne Brennan AM, MB BS, PhD, FACLM, MForensMed

Patricia Brennan was born in Hurstville, Sydney, on 15 April 1944. She attended St George Girls High School and graduated in medicine from the University of Sydney in 1968. After residency at Sydney Hospital, she worked at the Sudan Interior Mission hospitals in Jos, Nigeria, and Galmi, Niger. Patricia became aware of the poverty and powerlessness of many African women and the vulnerability of the powerless to hidden sexual and domestic abuse. Patricia returned to Australia in 1973 to become Haematology Registrar at Prince of Wales Hospital, Randwick, while also holding the position of general practice consultant for the Sudan Interior Mission. In 1977, she established a solo general practice at Summer Hill, which she maintained until 1986. During this time, Patricia also became Assistant Medical Director of the Sydney Square Breast Clinic. Throughout her life, Patricia accepted and sought opportunities to work against oppression and injustice. Each phase of her life was characterised by questioning, passion and intellectual rigour. In the 1980s and early 1990s, her defining work was a voluntary commitment outside of medicine to reform the position of women in the church, especially in her own Anglican church. As founding President of the Movement for the Ordination of Women from 1985 to 1989, she was a charismatic and inspirational leader with a ready wit and great presence, who galvanised support and sometimes opposition to the cause. She believed ordination would achieve a transformational change in the role of all women in the church and have a symbolic power in the wider fight against abuse and coercion. In 1995, she worked with World Vision, assessing funded health programs, including programs to combat sexual assault and to manage post-traumatic stress in children in refugee camps in Gaza and the West Bank, Israel. In 1996, while undertaking her doctorate in medical anthropology, Patricia commenced as a medical officer with the Liverpool/Fairfield Sexual Assault Service and, in 2001, she became its Medical Director. This resulted in the next stage of her vocation: calling on the medical and wider community to recognise the widespread and long-lasting trauma caused by sexual assault and family violence. She completed a Masters in Forensic Medicine from Monash University, developed specialist pathways for training and, at the Royal Prince Alfred Hospital, became the first Staff Specialist in Clinical Forensic Medicine specialising in sexual assault appointed to an emergency department in New South Wales. She was a Fellow of the Australasian College of Legal Medicine, a member of the Forensic and Medical Sexual Assault Clinicians Australia, and a founding committee member of the Australasian Association of Forensic Physicians. In 2009, she became acting Medical Director of the Clinical Forensic Medical Unit of the NSW Police Force, and was appointed a Visiting Fellow in Law at the University of NSW in 2010. She pushed for medical rigour in a field of medicine where there was a history of ill founded medical opinion contributing to grave injustices: the return of children to situations of abuse, failed prosecutions due to inadequate medical evidence and, occasionally, false convictions. Patricia’s achievements were recognised with a Bicentennial Woman of Achievement Award in 1988 and, in 1993, she was made a Member of the Order of Australia for services to the community, particularly as founding President of the Movement for the Ordination of Women. Patricia was a doctor of ready wit and apt speech who exercised leadership on big picture issues with passionate intelligence. She could be discouraged by frustration at the slowness of change, but she always returned with energy and creativity to the cause. All her struggles were motivated by a bold vision and a sense of calling. She died on 6 March 2011, 4 months after being diagnosed with pancreatic cancer. She is survived by her husband Robert, children Kate, Peter and James, and grandson Gabriel.

Rosemary A Isaacs

Cancer Research 17 October 2011 Free

BreastScreen-based mammography screening in women with a personal history of breast cancer, Western Australian study

Objective: To evaluate mammography screening outcomes in women with a personal history of breast cancer (PHBC), who have an increased risk of recurrent or new breast cancer, relative to women without PHBC.Design, setting and participants: Retrospective study of 713 191 screening mammograms from two groups of women — those with versus those without PHBC — who participated in the BreastScreen WA program in Western Australia between 1997 and 2006.Main outcome measures: Cancer detection rate (CDR), recall to assessment rate, recall positive predictive value (PPV) for cancer, and distribution of cancer characteristics within and between the two groups.Results: Screening detected 4125 breast cancers: CDR per 10 000 screens was significantly higher in women with PHBC (95.5; 95% CI, 78.3–112.7) than in women without PHBC (57.2; 95% CI, 55.4–58.9). Recall to assessment rate per 10 000 screens was lower in women with PHBC (385.2; 95% CI, 350.6–419.8) than in women without PHBC (504.9; 95% CI, 499.7–510.2). Recall PPV was higher for women with PHBC (24.8%; 95% CI, 21.0%–28.9%) than those without PHBC (11.2%; 95% CI, 10.9%–11.6%). Cancer characteristics were consistent with early detection (most were smaller than 2 cm and node-negative) and were similarly distributed in both groups, except for tumour grade, with PHBC women having fewer low-grade cancers and slightly more high-grade cancers than women without PHBC.Conclusions: The relative rate of cancer detection between women with PHBC and women without PHBC who attended an Australian population-based breast screening program was similar to estimates from international studies. Recall rates were within national standards. Screen-detected cancers had similar characteristics in both groups, except for tumour grade. These data support national integration of mammography screening for women with PHBC into BreastScreen, although evaluation of interval cancers will be necessary.

Nehmat Houssami MB BS, FAFPHM, PhD · Janette J Tresham BSc(Agric) · Lin Fritschi MB BS, FAFPHM, PhD · Liz E Wylie MB BS, FRANZCR

Should efforts to minimise DNA contamination of forensic swabs be standardised across Australia?

Forensic medical practitioners urgently require credentials and national guidelines Across Australia, health professionals from differing disciplines provide health care for victims of suspected assault, which may include collection of samples for forensic analysis. Although some have been trained to collect forensic samples, few hold professional qualifications in forensic medicine. The current lack of standards and credentialled training for collection of forensic samples (in a manner that minimises the risk of contamination) poses an unacceptable risk to individual doctors and nurses, the profession and to the criminal justice system. During the past decade, several high profile cases involving DNA contamination of evidence have been reported in the medical, legal and popular media. These cases highlight the costs in economic terms and in terms of human suffering, injustice and loss of confidence in the criminal justice system when errors occur because of DNA contamination. A swab, and materials collected onto a swab, for forensic DNA identification might become contaminated at any time from the collection stage to the final stage of DNA identification. The process of DNA identification is a lengthy one that involves a number of people operating at different locations, at different times. There are many opportunities for a swab, or the genetic material obtained from the swab, to become contaminated with another person’s DNA. It could be argued that there are two levels at which we should consider the need to avoid DNA contamination of swabs. First, there is a need to avoid contamination of a swab with DNA from a member of the public who might be inculpated in a crime. These individuals cannot easily be excluded as suspects. Second, there is a need to avoid contamination of a swab by DNA shed from a professional who has handled the swab or worked in the environment in which the swab was collected. By virtue of their employment, these individuals have a valid reason for their DNA being in the proximity of the swab. They might more easily be excluded as suspects, and most would readily volunteer to donate a reference sample to enable their DNA to be identified for the purpose of excluding them from further consideration in a criminal investigation. The compelling reason to avoid contaminating a swab with DNA from a medical professional or laboratory scientist is that the presence of any extraneous DNA affects the DNA scientists’ ability to interpret electropherograms. When mixed profiles are obtained, confidence in the scientists’ interpretation of the results is reduced. Some laboratories will not provide an interpretation of DNA results when a mixed profile of four or more individuals is obtained. What are the consequences when DNA contamination of a forensic swab occurs?Wrongful convictions of innocent individuals have occurred because of DNA misidentification and other DNA-related errors in Australia and other countries — an outcome regarded as intolerable in a civilised society. Examples of wrongful convictions that appear to have resulted from DNA contamination are shown in Box 1. Wrongful convictions have far-reaching consequences. In regions of the world where the death penalty exists, the outcome can be lethal. How has the legal system responded?As new case law increases everyone’s awareness of the phenomenon of secondary transfer of DNA, and techniques such as low-copy-number DNA amplification increase the risk of amplification of traces of contaminating DNA,6 defence lawyers are demonstrating greater willingness to challenge DNA evidence in court. In the United Kingdom, at Terence and David Reed’s unsuccessful appeal ([2009] EWCA Crim 2698) against their 2006 conviction for the murder of Peter Hoe, the defence counsel argued that shards of plastic said to be from a knife handle and found near the victim were contaminated with the brothers’ DNA. Prosecutors argued that the DNA connected the brothers to the murder weapon. (The appeal was dismissed as there was sufficient evidence for conviction beyond the doubts over the DNA evidence.) In 2008, the UK police conducted a review of the use of low-copy-number DNA amplification techniques in light of the increased risk of erroneous interpretation of DNA identification results.7 In Australia, Canberra man Steven Hillier was acquitted of his ex-wife’s murder at a retrial in April 2010 (R v Hillier [2010] ACTSC 33). He had been convicted of murder in 2004. The conviction was quashed in 2006, and the Australian Capital Territory Director of Public Prosecutions subsequently challenged the appeal and sought a retrial. Hillier’s counsel successfully argued that a possibility existed that his DNA had been secondarily transferred onto his estranged wife’s clothing and doona.2 Prominent Australian lawyers8-10 have provided advice for barristers and judges on matters to consider during cross-examination and guidelines for determining admissibility of DNA evidence in Australian courts. How have forensic scientists responded?Quality assurance activities within laboratories minimise the risk of DNA contamination. National standards exist (National Association of Testing Authorities [NATA]) and DNA laboratory scientists must be credentialled. Most scientists remain alert to the possibility of DNA contamination and openly acknowledge when contamination within a laboratory occurs. On rare occasions, scientists have denied responsibility for contamination or error. For example, the Victoria Police Forensic Services Centre (VPFSC) scientist involved in the contamination of a murdered child’s bib with a rape victim’s DNA suggested that an adventitious DNA match, not laboratory error, was responsible (inquest into the death of Jaidyn Leskie, Coroner Graeme Johnstone, July 2006). At the trial of a man wrongfully convicted of rape, the testimony of a VPFSC scientist suggests that the scientist had limited understanding of the potential for contamination at a site other than the VPFSC laboratory.5 How have clinical forensic medical practitioners responded?Justice Frank Vincent’s conclusions5 about environmental contamination of the swab that led to the wrongful conviction of Farah Jama (Box 1) has been a powerful influence for change in the practice of clinical forensic medicine in relation to suspected sexual assault in Australia. There are a number of areas of improvement driven by the Victorian Institute of Forensic Medicine (VIFM), which has developed, in consultation with others, interim practice arrangements that act as guidelines for the collection of samples for forensic analysis.11 Key areas for improvement include the equipment and procedures used to collect samples and the environment in which samples are collected. Swabs and slides within sexual assault kits should be as free of contaminating DNA as possible. Irradiation of swabs has proven to be an inadequate process for denaturing DNA. An unknown female suspect, linked to several unsolved serious crimes in Germany and Austria between 1993 and 2009, was eventually shown to be a worker involved with the manufacture of the swabs.12 Forensic-supply companies continue to develop and supply swabs, slides and kits that are increasingly easy to use and are designed to minimise the risk that DNA might inadvertently be transferred onto a swab via a swab sheath or equipment used during the procedure. Disposable single-use instruments such as pencils, pens, speculae, forceps and scissors are recommended. Documents for recording samples collected and envelopes used for transporting samples to a laboratory are treated to denature DNA. Currently, there is significant variation between regions in Australia in relation to the design and suitability for purpose of some of the facilities where forensic samples are collected. Some facilities are clearly not “fit for purpose”. The structure of the facility should enable restricted access to a limited number of known individuals, adequate and documented cleaning to DNA elimination standards, furniture and surfaces that are maintained in a DNA-clean state, storage of equipment and supplies that prevents reuse or replacement of supplies that might have been contaminated and appropriate disposal of used supplies. Furniture and equipment within the examining room should be kept to a minimum and all surfaces should be able to tolerate cleaning with bleach. There should be a flow of patients from the entrance area into the examination room then shower facility. Suspects should not be examined in the area where victims are examined. These recommendations were set out in the VIFM submission to the Vincent inquiry. Gloves must be worn and changed regularly, particularly during the interval between collecting samples from different sites and when labelling and packaging samples. In some overseas jurisdictions, medical practitioners shower and change clothing between cases. No agreement has yet been reached about the need for forensic practitioners to wear gowns, masks or hairnets. The requirement to use gowns and masks is likely to meet with opposition from paediatric forensic practitioners who are likely to express concern about the negative emotional impact that this apparel might have on child victims. Cleaning procedures need to be at a standard that will denature DNA. Hypochlorite bleach has been demonstrated in DNA laboratories to denature DNA and is used for routine cleaning of floors and walls, as well as for cleaning work surfaces. Techniques used to collect samples must ensure that material from one site is not inadvertently transferred to another site. Tamper-proof seals are used in some jurisdictions. How have the regulators responded?Following the release of the Vincent report, the Victorian Department of Justice sought to rectify problems within the Victorian centres where sexual assault victims are examined. To date, changes to cleaning practices and modifications to a small number of units have occurred, primarily as a direct request to health services, where most facilities are located. Although it was a clear recommendation in the Vincent report, no reduction in the number of sites where sexual assault victims are examined has occurred. In July 2010, the UK Home Office published the second draft of the Codes of practice and conduct for forensic science providers and practitioners in the criminal justice system.13 The document was informed by a critical review of low-copy-number DNA amplification techniques and the use of this technology within courts. This comprehensive discussion document is regarded to be the first step in a process aimed at achieving better governance and higher standards throughout the sector. In Australia and New Zealand, standards are being developed in line with the strategy for 2009–2012 developed by the Australia New Zealand Policing Advisory Agency National Institute of Forensic Science.14 Forensic science centres are assessed according to explicit criteria that test quality and the reliability of results in order to achieve NATA accreditation. Within government in Australia, particularly Departments of Justice, there is an increasing awareness of the need for standards, monitoring and governance of those standards and the need for caution in relation to the use of DNA evidence in courts. The Public Defenders Office in New South Wales offered succinct advice to the legal profession in relation to the use of DNA evidence in court.15,16 In May 2011, the High Court, the highest court of appeal in Australia, dismissed convicted Canberra rapist Benjamin Forbes’ application for an appeal on the basis that he had been convicted on DNA evidence alone.17 This judgement indicates confidence in DNA technology and its use in the Australian criminal justice system. At present, there is no governing or regulatory body for clinical forensic medical practice. Doctors are accountable to their employer and to the Medical Board of Australia. Nurses are likewise accountable to their employer and the Nursing and Midwifery Board of Australia. Most forensic practitioners belong to professional colleges, such as the Royal Australasian College of Physicians, the Royal Australasian College of General Practitioners, and the Australasian College of Legal Medicine. There is no overarching collegiate body to certify successful completion of forensic medical training. The intercollegiate working group that developed guidelines for genital examinations of girls and young women did not provide explicit advice about the collection of samples for forensic analysis when sexual assault is suspected.18 The Australasian Association of Forensic Physicians has demonstrated an interest in developing standards and guidelines for collection of forensic samples, but this work is in its infancy. Where to now?It is unlikely that the medical profession will ever be able to exclude the possibility that a swab has become contaminated with DNA. The task before us is to minimise the risk, and to be seen to be minimising the risk, of DNA contamination. Forensic medical practitioners urgently require national guidelines and standards to guide and govern forensic medical practice (Box 2). We also need: a national collegiate body to certify that practitioners have met training requirements and have demonstrated required competencies; a national group to negotiate across state boundaries with employers and governments to ensure that we are enabled and supported to provide a high standard of forensic medical care and to maintain an effective workforce; police and forensic scientists to share with us the desire to safeguard the integrity of forensic samples and the results obtained from their analysis; a well informed public that has realistic expectations of forensic services; a legal system that challenges, questions and pushes us to consider our failings; and a health system that supports and encourages us to continue to improve. 1 DNA contamination resulting in wrongful identification of suspect Country Year Case Contamination site Criminal charge Consequences for wrongly accused New Zealand 1998 Profile N1 Laboratory Murder × 2 Financial records seized; intense police investigation; no conviction Canada 2001 Gregory Turner2 Laboratory Murder 27 months’ jail Australia 2004 Steven Hillier3 Before collection Murder Conviction; successful appeal Australia 2008 Russell Gesah4 Laboratory cold-case match Murder × 2 Charges dropped Australia 2008 Farah Jama5 Collection Rape 15 months’ jail 2 A multicomponent plan for national clinical practice standards regarding collection of forensic samples for DNA identification Task Responsible group Strategy Authorising body Determine clinical practice guidelines Forensic physicians, paediatricians and nurses Working group evaluation of evidence; consensus; recommendations Currently none; potentially AAFP Develop national standards for handling of forensic samples ANZPAA National Institute of Forensic Science Multidisciplinary working group evaluation of evidence; consensus ANZPAA National Institute of Forensic Science Determine professional training requirements College or university department of forensic medicine Curriculum development and implementation Currently none; potentially VIFM and/or Monash University Certification of competency College or university department of forensic medicine Successful completion of training program; demonstrated competency Currently none; potentially VIFM and/or Monash University or alternative Governance of professional practice clinical forensic medicine Employing organisations Organisational standards; monitoring practice Multiple, such as state centres providing clinical forensic medicine services Monitor and enforce clinical forensic medicine standards across Australia National body A new national college of forensic medicine Currently none; potentially RACP, Australasian College of Legal Medicine or new national college of forensic medicine AAFP = Australasian Association of Forensic Physicians. ANZPAA = Australia New Zealand Policing Advisory Agency. RACP = Royal Australasian College of Physicians. VIFM = Victorian Institute of Forensic Medicine.

J Anne S Smith MB BS, FRACP

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