Air pollution mortality benefits of sustained COVID-19 mobility restrictions in Australian cities.

OBJECTIVES: Emissions from road traffic, power generation and industry were substantially reduced during pandemic lockdown periods globally. Thus, we analysed reductions in traffic-related air pollution in Australian capital cities during March-April 2020 and then modelled the mortality benefits that could be realised if similar reductions were sustained by structural policy interventions. STUDY DESIGN: Satellite, air pollution monitor and land use observations were used to estimate ground-level nitrogen dioxide (NO2) concentrations in all Australian capital cities during: (a) a typical year with no prolonged air pollution events; (b) a hypothetical sustained reduction in NO2 equivalent to the COVID-19 lockdowns. METHODS: We use the WHO recommended NO2 exposure-response coefficient for mortality (1.023, 95 % CI: 1.008-1.037, per 10 µg/m3 annual average) to assess gains in life expectancy and population-wide years of life from reduced exposure to traffic-related air pollution. RESULTS: We attribute 1.1 % of deaths to anthropogenic NO2 exposures in Australian cities, corresponding to a total of 13,340 years of life lost annually. Although COVID-19-related reductions in NO2 varied widely between Australian cities during April 2020, equivalent and sustained reductions in NO2 emissions could reduce NO2-attributable deaths by 27 %, resulting in 3348 years of life gained annually. CONCLUSIONS: COVID-19 mobility restrictions reduced NO2 emissions and population-wide exposures in Australian cities. When sustained to the same extent by policy interventions that reduce fossil fuel consumption by favouring the uptake of electric vehicles, active travel and public transport, the health, mortality and economic benefits will be measurable in Australian cities.

"Watch Me Grow- Electronic (WMG-E)" surveillance approach to identify and address child development, parental mental health, and psychosocial needs: study protocol.

BACKGROUND: The COVID-19 pandemic and the associated economic recession has increased parental psychosocial stress and mental health challenges. This has adversely impacted child development and wellbeing, particularly for children from priority populations (culturally and linguistically diverse (CALD) and rural/regional communities) who are at an already increased risk of health inequality. The increased mental health and psychosocial needs were compounded by the closure of in-person preventive and health promotion programs resulting in health organisations embracing technology and online services. Watch Me Grow- Electronic (WMG-E) - developmental surveillance platform- exemplifies one such service. WMG-E was developed to monitor child development and guide parents towards more detailed assessments when risk is identified. This Randomised Controlled Trial (RCT) aims to expand WMG-E as a digital navigation tool by also incorporating parents' mental health and psychosocial needs. Children and families needing additional assessments and supports will be electronically directed to relevant resources in the 'care-as-usual' group. In contrast, the intervention group will receive continuity of care, with additional in-person assessment and 'warm hand over' by a 'service navigator' to ensure their needs are met. METHODS: Using an RCT we will determine: (1) parental engagement with developmental surveillance; (2) access to services for those with mental health and social care needs; and (3) uptake of service recommendations. Three hundred parents/carers of children aged 6 months to 3 years (recruited from a culturally diverse, or rural/regional site) will be randomly allocated to the 'care-as-usual' or 'intervention' group. A mixed methods implementation evaluation will be completed, with semi-structured interviews to ascertain the acceptability, feasibility and impact of the WMG-E platform and service navigator. CONCLUSIONS: Using WMG-E is expected to: normalise and de-stigmatise mental health and psychosocial screening; increase parental engagement and service use; and result in the early identification and management of child developmental needs, parental mental health, and family psychosocial needs. If effective, digital solutions such as WMG-E to engage and empower parents alongside a service navigator for vulnerable families needing additional support, will have significant practice and policy implications in the pandemic/post pandemic period. TRIAL REGISTRATION: The trial (Protocol No. 1.0, Version 3.1) was registered with ANZCTR (registration number: ACTRN12621000766819 ) on July 21st, 2021 and reporting of the trial results will be according to recommendations in the CONSORT Statement.

Predictors of developmental surveillance completion at six months of age in south western Sydney.

BACKGROUND: While developmental surveillance programs promote early identification of child developmental problems, evidence has indicated suboptimal uptake. This study aimed to identify predictors of developmental surveillance completion at 6 months postpartum. METHODS: Questionnaires were administered to the parents of 510 infants who were born in south western Sydney, Australia over a 22-month period. Attendance for developmental screening and completion of the Parents' Evaluation of Developmental Status (PEDS) at 6 months postpartum were modelled separately using multivariable logistic regression. RESULTS: Developmental surveillance attendance was predicted by higher levels of maternal education, annual income and being informed about checks. PEDS completion at 6 months of age was predicted by higher income and being informed, as well as being married, employed, speaking English at home, full-term birth and the professional status of the practitioner completing the check. CONCLUSIONS: Barriers to developmental surveillance included low socioeconomic status, linguistic diversity and possible gaps in parental knowledge and professional education. Developmental surveillance rates may be increased by the addition of targeted parental and professional support within current universal frameworks.

Predictors of large and small for gestational age birthweight in offspring of women with gestational diabetes mellitus.

AIM: To identify predictors of large and small for gestational age in women with gestational diabetes mellitus. METHODS: A retrospective audit of clinical data analysed for singleton births in women diagnosed with gestational diabetes by Australasian Diabetes in Pregnancy Society guidelines from 1994 to 2009. Exclusions were: incomplete data, delivered at < 36 weeks gestation and/or last recorded weight > 4 weeks pre-delivery. We assessed: pre-pregnancy BMI, ethnicity, total maternal weight gain, weight gain before and after treatment initiation for gestational diabetes, HbA(1c) at gestational diabetes presentation and treatment modality (diet or insulin) and smoking. Birthweight was assessed using customized percentile charts (large for gestational age > 90th; small for gestational age < 10th percentile). Multiple regression analyses were undertaken; statistical significance was p < 0.05. RESULTS: There were 1695 women first seen at (mean ± sd) 28.1 ± 5.3 weeks gestation (range 6-39). Ethnic mix was South-East Asian 36.7%, Middle Eastern 27.6%, European 22.4%, Indian/Pakistani 8.6%, Samoan 1.9%, African 1.5% and Maori 1.1%. Therapy was diet 69.1% and insulin 30.9%. Mean total weight gain was 12.3 ± 6.1 kg, the majority (10.6 ± 6.0 kg), gained before dietary intervention. There were 7.9% small for gestational age and 15.2% large for gestational age births. Significant independent large for gestational age predictors were: weight gain before intervention, pre-pregnancy BMI, weight gain after intervention and treatment type, but not HbA1c or smoking. Significant small for gestational age predictors were: weight gain before intervention, weight gain after intervention, but not pre-pregnancy BMI, HbA(1c) or smoking. CONCLUSION: Conventional treatment for gestational diabetes mellitus concentrates on management of blood glucose levels. The trends identified here emphasize the need to also address pregnancy weight gain stratified by pre-pregnancy BMI.

The clinical significance of overt diabetes in pregnancy.

AIM: To explore clinical implications of overt diabetes in pregnancy on antenatal characteristics, adverse neonatal outcome and diabetes risk post-partum. METHODS: Retrospective audit of prospectively collected data for all patients with gestational diabetes mellitus from 1993 to 2010. We defined overt diabetes in pregnancy as an HbA(1c) ≥ 8 mmol/mol (6.5%) or a fasting plasma glucose ≥ 7.0 mmol/l, or a 2-h glucose level ≥ 11.1 mmo/L on a 75-g oral glucose tolerance test as a surrogate for a random glucose ≥ 11.1 mmo/l. RESULTS: Our audit identified 1579 women with gestational diabetes and 254 with overt diabetes in pregnancy. Women with overt diabetes in pregnancy were diagnosed earlier in pregnancy, had a higher number of risk factors for gestational diabetes, higher antenatal HbA(1c), fasting and 2-h glucose levels, higher pre-pregnancy BMI and higher insulin use and dosage requirements than those with gestational diabetes. Overt diabetes in pregnancy was associated with an increased rate of large-for-gestational-age infant, neonatal hypoglycaemia and shoulder dystocia. Of the 133 patients with overt diabetes in pregnancy who attended a follow-up oral glucose tolerance test at 6-8 weeks post-partum, 21% had diabetes, 37.6% had impaired fasting glucose or impaired glucose tolerance, whilst 41.4% returned to normal glucose tolerance. CONCLUSION: In this patient cohort, overt diabetes in pregnancy significantly increased the risk of adverse pregnancy outcomes and post-partum impaired glucose regulation, but should not be regarded as synonymous with underlying diabetes. Two-hour glucose following a 75-g glucose load is a poor predictor of post-partum diabetes.

Towards an ontology for data quality in integrated chronic disease management: a realist review of the literature.

PURPOSE: Effective use of routine data to support integrated chronic disease management (CDM) and population health is dependent on underlying data quality (DQ) and, for cross system use of data, semantic interoperability. An ontological approach to DQ is a potential solution but research in this area is limited and fragmented. OBJECTIVE: Identify mechanisms, including ontologies, to manage DQ in integrated CDM and whether improved DQ will better measure health outcomes. METHODS: A realist review of English language studies (January 2001-March 2011) which addressed data quality, used ontology-based approaches and is relevant to CDM. RESULTS: We screened 245 papers, excluded 26 duplicates, 135 on abstract review and 31 on full-text review; leaving 61 papers for critical appraisal. Of the 33 papers that examined ontologies in chronic disease management, 13 defined data quality and 15 used ontologies for DQ. Most saw DQ as a multidimensional construct, the most used dimensions being completeness, accuracy, correctness, consistency and timeliness. The majority of studies reported tool design and development (80%), implementation (23%), and descriptive evaluations (15%). Ontological approaches were used to address semantic interoperability, decision support, flexibility of information management and integration/linkage, and complexity of information models. CONCLUSION: DQ lacks a consensus conceptual framework and definition. DQ and ontological research is relatively immature with little rigorous evaluation studies published. Ontology-based applications could support automated processes to address DQ and semantic interoperability in repositories of routinely collected data to deliver integrated CDM. We advocate moving to ontology-based design of information systems to enable more reliable use of routine data to measure health mechanisms and impacts.

The University of NSW electronic practice based research network: disease registers, data quality and utility.

INTRODUCTION: Accurate well-maintained registers are a prerequisite to co-ordinated care of patients with chronic diseases. Their effectiveness in enabling improved management is dependent on the quality of the information captured. This paper provides an overview into the methodology and data quality of the electronic Practice Based Research Network. METHODS: Clinical records with no identifying information are routinely extracted from four general practices. The data are linked in the data warehouse. Data quality is assessed for completeness, correctness and consistency. Reports on data quality are given back to practices and semi-structured interviews provide information to interpret the results and discuss how data quality could be improved. FINDINGS: Data quality is mostly complete for sex and date of birth but indigenous status, smoking and weight were incomplete. There are generally high levels of correctness and internal consistency. Completeness of records in assisting the management of diabetes patients using the annual cycle of care was poor. GPs often use the progress notes to enter information during the consultation and coding diagnoses was considered onerous. DISCUSSION: The routine capture of electronic clinical health records from primary health care and health services can be used to monitor performance and improve the quality of clinical records. There is a need for accurate and comprehensive clinical records to ensure the safety and quality of clinical practice. Understanding the true reasons for poor data quality is complex. Having a community-based research network may assist in answering some of these questions. CONCLUSION: Electronic health records are increasingly being used for secondary research and evaluation, beyond the primary purpose of supporting clinical care. The data must be of sufficient quality to support these purposes.

Subconjunctival triamcinolone treatment for non-necrotising anterior scleritis.

AIMS: To determine the outcome of treatment with subconjunctival triamcinolone acetate for non-necrotising anterior scleritis and to review the literature on this treatment. METHODS: A retrospective, interventional case series of 12 patients who had failed systemic therapy, treated with 25 subconjunctival triamcinolone for non-necrotising anterior scleritis. RESULTS: Complete resolution of symptoms and signs of scleral inflammation occurred after 23 out of the 25 injections administered. For the remaining two injections, it was necessary to increase oral corticosteroids to obtain complete resolution. No treated eye lost vision after subconjunctival triamcinolone therapy. No patient developed scleral necrosis after subconjunctival therapy. Four patients developed a rise in intraocular pressure after treatment. The mean follow-up was 9 months with a range of 1-20 months. Scleritis relapsed in 38% of eyes and required repeat subconjunctival triamcinolone therapy. CONCLUSION: This study provides evidence that subconjunctival triamcinolone therapy is an efficacious treatment with a prolonged duration of effect in selected patients with non-necrotising scleritis.

Water fluoridation in the Blue Mountains reduces risk of tooth decay.

BACKGROUND: In April 1992, the fluoride concentration in the Blue Mountains water supply was adjusted to 1 mg/L. Baseline dmft/DMFT has been determined in children attending schools in the region and in the adjacent reference region of Hawkesbury, fluoridated since 1968. The aim of this study was to evaluate the effect of the water fluoridation programme in the Blue Mountains. METHODS: In 2003, children attending the same schools were sampled. Residential history data were obtained by questionnaire and caries experience was assessed according to WHO guidelines. The analysis was restricted to lifelong resident children aged 5-11 years. RESULTS: The baseline and follow-up dmft scores for Blue Mountains children aged 5-8 years were 2.36 and 0.67, respectively. The age-adjusted decrease in odds of experiencing one or more dmft due to fluoridation was 0.26 (CI(95) 0.19, 0.37). The corresponding DMFT scores for Blue Mountains children aged 8-11 were 0.76 and 0.21 and the corresponding decrease in odds of experiencing one or more DMFT due to fluoridation was 0.25 (CI(95) 0.16, 0.40). CONCLUSIONS: Tooth decay reduction observed in the Blue Mountains corresponds to high rates reported elsewhere and demonstrates the substantial benefits of water fluoridation.

Influence of previous pregnancy outcomes and continued smoking on subsequent pregnancy outcomes: an exploratory study in Australia.

OBJECTIVE: To examine the influence of continued smoking and previous pregnancy outcomes on subsequent pregnancy outcomes. DESIGN: Retrospective descriptive epidemiological study. SETTING: New South Wales, Australia, 1994-2004. POPULATION: Mothers who delivered two consecutive singleton births. METHODS: Bivariate and multiple logistic regression analyses were used to explore the influence of continued smoking on subsequent pregnancy outcomes. MAIN OUTCOME MEASURES: Subsequent preterm birth (PTB), low birthweight (LBW) and perinatal deaths. RESULTS: The findings showed that in addition to maternal and neonatal characteristics, birth outcomes in subsequent pregnancies were affected by poor birth outcomes in previous pregnancy. Previous PTB, short birth interval, antenatal care, gestational diabetes and smoking habits in two successive pregnancies had relatively strong association with a subsequent PTB and LBW. Mothers who continued to smoke in subsequent pregnancies were more likely to have adverse pregnancy outcomes compared with others. A change from smoking in first pregnancy to not smoking in next pregnancy had reduced the chance of a subsequent PTB and LBW. The risk of a subsequent preterm and LBW delivery increased with the amount of smoking during the second pregnancy. For mothers who remain as moderate smokers in subsequent pregnancies, the odds ratios for a PTB and LBW delivery were significantly lower than those who remain as heavy smokers. CONCLUSIONS: Effective interventions to help women to stop smoking during pregnancy could reduce the risk of adverse obstetric and pregnancy outcomes. Strategies to reduce the prevalence of smoking during pregnancy may include intense intervention for women who have had smoking-related adverse outcomes in a previous pregnancy.

Use of ocular hypotensive prostaglandin analogues in patients with uveitis: does their use increase anterior uveitis and cystoid macular oedema?

AIM: A retrospective comparative case series was studied to determine whether the use of prostaglandin (PG) analogues to treat raised intraocular pressure (IOP) in patients with uveitis resulted in an increase in the frequency of anterior uveitis or cystoid macular oedema (CMO). METHODS: 163 eyes of 84 consecutive patients with uveitis and raised IOP treated with a PG analogue at two tertiary referral uveitis clinics were identified over a 3-month period. Control eyes were selected as those uveitic eyes of the same patients, which were treated with topical IOP-lowering agent(s) other than a PG analogue. Pretreatment IOP was compared with the mean IOP during PG analogue treatment. The frequency of anterior uveitis and CMO during PG analogue treatment was compared with the frequency of these complications in the control eyes during non-PG IOP-lowering treatment. RESULTS: Significant IOP reductions were observed during PG analogue treatment. There was no significant difference in the frequency of anterior uveitis in those eyes treated with PG analogues and those treated with non-PG agents (p = 0.87, Fisher exact test). None of the 69 uveitic eyes without a previous history of CMO developed this complication. There was no increase in the frequency of visually significant CMO during PG treatment compared with that during non-PG treatment (p = 0.19, Fisher exact test). CONCLUSION: This study demonstrates that PG analogues are potent topical medications for lowering raised IOP in patients with uveitis and are not associated with increased risk of CMO or anterior uveitis.

Hepatocellular carcinoma in Sydney South West: late symptomatic presentation and poor outcome for most.

BACKGROUND: Hepatocellular cancer (HCC) is a serious complication of cirrhosis and chronic hepatitis B infection. The aim of the study was to determine the characteristics of patients with HCC presenting within the South West Sydney area, including an analysis of the rates and benefits of hepatocellular surveillance. METHODS: Data from patients with HCC presenting to Liverpool and Bankstown Hospitals from July 1993 to June 2003 were analysed retrospectively, predominantly from hospital records. RESULTS: Of the 151 HCC patients, 41% were Asian born. Most of the patients required an interpreter. Chronic viral hepatitis infection was present in 91 patients, of whom only 7% had previously received antiviral therapy. Alcohol alone was considered responsible in 31 patients. Cirrhosis could be documented in 58% of patients. Most of the patients (75%) presented symptomatically. The median survival was 5.1 months. When HCC was detected by surveillance, the tumours were slightly but not significantly more likely to be operable and the patients tended to be offered some form of active treatment more frequently. Multivariate analysis identified detection by surveillance, lower Child-Pugh score, smaller tumour size and eligibility for some form of treatment to be associated with a more favourable outcome. CONCLUSION: We observed low rates of surveillance for HCC, low recognition of cirrhosis before development of HCC and low rates of prior treatment of viral hepatitis. The poor outcome of HCC in the small group who had some sort of community surveillance is also a concern requiring further investigation.

Patient perceptions of osteomyelitis, septic arthritis and prosthetic joint infection: the psychological influence of methicillin-resistant Staphylococcus aureus.

INTRODUCTION: Patients form their own representations of their illness, which can be important determinants of their coping and influence outcome. Our aims were to (i) assess patient perceptions of osteomyelitis, septic arthritis and prosthetic joint infection, (ii) compare perceptions of methicillin-resistant Staphylococcus aureus (MRSA) with non-MRSA infection and (iii) investigate the emotional aspects of these infections. METHODS: A questionnaire was developed from the 'Illness Perception Questionnaire' of Weinman et al.with additional questions assessing emotional response. This was offered to all patients with osteomyelitis, septic arthritis and prosthetic joint infection attending the Liverpool Hospital Infectious Diseases Outpatient Clinic during a 3-month period. RESULTS: There were 91 respondents--25 with MRSA infection, 14 with MRSA colonization and 52 without MRSA. Seventy-nine per cent of all respondents felt that their infection was very serious and 76% felt their infection had had major consequences on their life. On multivariate analysis MRSA was associated with a greater emotional effect; the consequences and emotional effects of infection were greater in younger people and prosthetic joint infection was associated with less sense of control or cure. CONCLUSION: Osteomyelitis, septic arthritis and prosthetic joint infection have a significant effect on an individual. Ongoing support and education are important, particularly for the young, those with prosthetic joint infection and patients with MRSA.

Childhood asthma and return to school in Sydney, Australia.

OBJECTIVES: To describe the seasonal pattern of hospital admissions for childhood asthma in Sydney, Australia and investigate the relationship between these admissions and time of return to school. STUDY DESIGN: Time-series analysis of daily hospital admissions for childhood asthma in Sydney from 1994 to 2000. METHODS: We defined the time series of all asthma-related hospital admissions in Sydney between 1994 and 2000 for age groups 1-4 and 5-14 years. We analysed the time series for each age group using a generalized additive model with a log-link function, an offset term and quasi-likelihood estimation. Daily admissions were modelled using penalised regression splines adjusting for long term trends, school terms and holidays, weekday and influenza epidemics. RESULTS: After adjusting for potential confounding, the risk of asthma admission increased to a peak between 2 and 4 weeks after the first day of school in each term and varied between 1.5 and 3 times the risk prior to return to school for both age groups. The largest increase in asthma risk occurring in term one after the long summer holiday. The increase in admission risk began soon after the first day of school of each term for school age children 5-14 years, but not in pre-school age children 1-4 years. CONCLUSIONS: Returning to school after term holidays is strongly associated with increased risk of hospital admissions for asthma in children, especially following the long summer holiday. Preventive measures focused on return to school have the potential to substantially decrease admissions for asthma in children.

The influence of antenatal and maternal factors on stillbirths and neonatal deaths in New South Wales, Australia.

This study identified the influences of maternal socio-demographic and antenatal factors on stillbirths and neonatal deaths in New South Wales, Australia. Bivariate and multivariate analyses were used to explore the association of selected antenatal and maternal characteristics with stillbirths and neonatal deaths. The findings of this study showed that stillbirths and neonatal deaths significantly varied by infant sex, maternal age, Aboriginality, maternal country of birth, socioeconomic status, parity, maternal smoking behaviour during pregnancy, maternal diabetes mellitus, maternal hypertension, antenatal care, plurality of birth, low birth weight, place of birth, delivery type, maternal deaths and small gestational age. First-born infants, twins and infants born to teenage mothers, Aboriginal mothers, those who smoked during the pregnancy and those of lower socioeconomic status were at increased risk of stillbirths and neonatal deaths. The most common causes of stillbirths were conditions originating in the perinatal period: intrauterine hypoxia and asphyxia. Congenital malformations, including deformities and chromosomal abnormalities, and disorders related to slow fetal growth, short gestation and low birth weight were the most common causes of neonatal deaths. The findings indicate that very low birth weight (less than 2,000 g) contributed 75.6% of the population-attributable risks to stillbirths and 59.4% to neonatal deaths. Low gestational age (less than 32 weeks) accounted for 77.7% of stillbirths and 87.9% of neonatal deaths. The findings of this study suggest that in order to reduce stillbirths and neonatal deaths, it is essential to include strategies to predict and prevent prematurity and low birth weight, and that there is a need to focus on anti-smoking campaigns during pregnancy, optimizing antenatal care and other healthcare programmes targeted at the socially disadvantaged populations identified in this study.

Technology enhancements and changes in radiotherapy throughput in New South Wales.

AIMS: To assess the effect that the age of linear accelerators and recent changes in technology have had on linear accelerator throughput in New South Wales, Australia. MATERIALS AND METHODS: Duration was measured (time of patient entry into the treatment room to time of exit) of each radiotherapy treatment fraction delivered on each linear accelerator over a 5-day period. Patient-, treatment- and equipment-based variables were collected for all treatment fractions, and assessed for their effect on fraction duration. Comparisons were made between these data and similar productivity data collected from a study carried out in 1996. Since the sample sizes for both the study periods were large enough, the distributions of the means were assumed normal (Central Limit Theorem). Specific analyses were carried out to assess the affect that new technologies, such as automatic field-sequencing (AFS) and multi-leaf collimator (MLC), have had on fraction duration. RESULTS: A total of 12 892 treatment fields and 4316 treatment fractions were delivered on 27 linear accelerators over 135 days. Comparison between the 2003 and 1996 productivity data showed an increase in the mean number of patients treated per hour by 11% and fields treated per hour by 31%. The mean number of fields treated per fraction increased by 15%. The mean fraction duration was reduced by 13% for linear accelerators of less than the median age of 7 years that were equipped with MLC/AFS, or both, compared with older linear accelerators without AFS and MLC. This reduction was more obvious for complex techniques, such as four-field breast treatments (27% decrease in fraction duration). The mean number of fields treated per hour was 43% more on the newer machines equipped with AFS and MLC. CONCLUSIONS: An increase in productivity has been observed between the 1996 and 2003 study periods, as measured by patients or fields per hour, despite an increase in treatment complexity as measured by fields per fraction. The application of AFS and MLC, and the use of newer linear accelerators, significantly shortened the mean duration per fraction for the common treatment techniques.

The development of a new basic treatment equivalent model to assess linear accelerator throughput.

AIMS: The basic treatment equivalent (BTE) model was developed in 1996 in an attempt to improve the measurement of linear accelerator throughput in radiotherapy. This study aimed to assess the effect of treatment set-up and patient characteristics on fraction duration, to update the BTE model and to determine the better throughput measure between fields per hour and BTE per hour. MATERIALS AND METHODS: Stopwatch measurements of the duration of each radiotherapy treatment fraction delivered on each linear accelerator in participating New South Wales radiation oncology departments over a 5-day period in 2003 were undertaken. Patient, equipment and staff data were collected to assess the effect of these variables on fraction duration. A new BTE equation was derived, including the most significant variables. Statistical comparison of fields and BTE per unit time was made to assess the better predictor of fraction duration. RESULTS: Data collected on 27 linear accelerators in 13 departments included a total of 135 days of linear accelerator operation, 4316 fractions and 12 892 treatment fields. Seventeen factors significantly influenced fraction duration (P < 0.01). These accounted for 46% of the total variance in the models. The eight most influential predictors of prolonged fraction duration were included in the BTE model. These were as follows: high number of fields, high number of port films/electronic portal imaging, absence of automatic field-sequencing and multi-leaf collimation, high number of junctions, use of bolus and first fraction of a treatment course. The BTE per hour was shown to be a better predictor of throughput than fields per hour. CONCLUSIONS: The BTE model is a better measure of linear accelerator throughput. It incorporates weightings for treatment and patient factors that significantly influenced fraction duration. This measure could be routinely collected by the radiation oncology departments and included in the electronic radiotherapy information systems.

Impact of ambient air pollution on birth weight in Sydney, Australia.

BACKGROUND: Studies in Asia, Europe, and the Americas have provided evidence that ambient air pollution may have an adverse effect on birth weight, although results are not consistent. METHODS: Average exposure during pregnancy to five common air pollutants was estimated for births in metropolitan Sydney between 1998 and 2000. The effects of pollutant exposure in the first, second, and third trimesters of pregnancy on risk of "small for gestational age" (SGA), and of pollutant exposure during pregnancy on birth weight were examined. RESULTS: There were 138,056 singleton births in Sydney between 1998 and 2000; 9.7% of babies (13,402) were classified as SGA. Air pollution levels in Sydney were found to be quite low. In linear regression models carbon monoxide and nitrogen dioxide concentrations in the second and third trimesters had a statistically significant adverse effect on birth weight. For a 1 part per million increase in mean carbon monoxide levels a reduction of 7 (95% CI -5 to 19) to 29 (95% CI 7 to 51) grams in birth weight was estimated. For a 1 part per billion increase in mean nitrogen dioxide levels a reduction of 1 (95% CI 0 to 2) to 34 (95% CI 24 to 43) grams in birth weight was estimated. Particulate matter (diameter less than ten microns) in the second trimester had a small statistically significant adverse effect on birth weight. For a 1 microgram per cubic metre increase in mean particulate matter levels a reduction of 4 grams (95% CI 3 to 6) in birth weight was estimated. CONCLUSION: These findings of an association between carbon monoxide, nitrogen dioxide, and particulate matter, and reduction in birth weight should be corroborated by further study.

Direct comparison of 18F-fluorodeoxyglucose coincidence gamma camera tomography with gallium scanning for the staging of lymphoma.

BACKGROUND: The present study compared the performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) using a coincidence dual-head gamma camera (FDG Co-PET) with 67gallium scinti graphy (GS) in pretreatment staging of lymphoma. METHODS: A total of 46 patients underwent FDG Co-PET, computed tomography (CT) scanning and GS for pretreatment staging of lymphoma (40 newly diagnosed and recurrence) between November 1997 and December 1999. RESULTS: Histological subgroups comprised low grade (8 patients), intermediate grade (25) high-grade (3) non-Hodgkin's lymphoma and Hodgkin's disease (10). Based on clinical assessment, CT scan findings and biopsy, 100 nodal sites and 15 extra-nodal sites were deemed positive. FDG Co-PET was superior to GS in nodal site positivity rate (97%vs 79%, P < 0.0001). Compared with GS, FDG Co-PET detected 39 more abnormal sites in 22 patients (48%), of which 28 sites were validated by biopsy, CT and/or progress FDG Co-PET scanning. There was only one proven false negative FDG site in the spleen. CT + FDG Co-PET led to upstaging in 2 patients (4%), compared to CT + GS. CONCLUSION: FDG Co-PET shows potential for providing an accurate means for pretreatment staging of lymphoma and can detect extra sites of disease activity compared to GS.

An assessment of basic treatment equivalent at Cookridge Hospital.

The Australian model of Basic Treatment Equivalent (BTE) for measuring radiotherapy treatment productivity was developed for and tested within a busy UK radiotherapy centre and the results assessed against three other BTE models. The department's productivity was compared for three different models of treatment machine. Treatment fraction durations were timed for 362 consecutive treatment episodes on three treatment machines at Cookridge Hospital. Leeds. The treatment factors found to have a statistically significant impact on fraction duration were: initial fraction; patient mobility; number of fields; treatment intent and the type of treatment machine. In comparison with the Australasian study, shorter mean fraction times were shown for a number of types of treatment, carried out on one particular linac type, which had multileaf collimation (MLC). The average non-operational time was 17% at Cookridge (31% in Australasia) with overall productivity gains. This efficiency may have been achieved partly by a higher number of staff per machine (five rather than four) and the presence of newer technology such as MLC. A BTE model was derived for Cookridge using the significant treatment factors and compared to other published models. The Cookridge model was most sensitive in predicting productivity. BTE models developed by other groups were also excellent in predicting treatment duration. The development of a BTE model is potentially applicable in the U.K. radiotherapy community at a time when optimizing activity per radiographer is key to minimizing waiting times.