54 results on '"Macaskill, Petra"'
Search Results
2. Pilot trial of digital breast tomosynthesis (3D mammography) for population-based screening in BreastScreen Victoria.
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Houssami, Nehmat, Lockie, Darren, Clemson, Michelle, Pridmore, Vicki, Taylor, David, Marr, Georgina, Evans, Jill, and Macaskill, Petra
- Abstract
Objectives: To estimate detection measures for tomosynthesis and standard mammography; to assess the feasibility of using tomosynthesis in population-based screening for breast cancer.Design, Setting: Prospective pilot trial comparing tomosynthesis (with synthesised 2D images) and standard mammography screening of women attending Maroondah BreastScreen, a BreastScreen Victoria service in the eastern suburbs of Melbourne.Participants: Women at least 40 years of age who presented for routine breast screening between 18 August 2017 and 8 November 2018.Main Outcome Measures: Cancer detection rate (CDR); proportion of screens that led to recall for further assessment.Results: 5018 tomosynthesis and 5166 standard mammography screens were undertaken in 10 146 women; 508 women (5.0% of screens) opted not to undergo tomosynthesis screening. With tomosynthesis, 49 cancers (40 invasive, 9 in situ) were detected (CDR, 9.8 [95% CI, 7.2-13] per 1000 screens); with standard mammography, 34 cancers (30 invasive, 4 in situ) were detected (CDR, 6.6 [95% CI, 4.6-9.2] per 1000 screens). The estimated difference in CDR was 3.2 more detections (95% CI, -0.32 to 6.8) per 1000 screens with tomosynthesis; the difference was greater for repeat screens and for women aged 60 years or more. The recall rate was greater for tomosynthesis (4.2%; 95% CI, 3.6-4.8%) than standard mammography (3.0%; 95% CI, 2.6-3.5%; estimated difference, 1.2%; 95% CI, 0.46-1.9%). The median screen reading time for tomosynthesis was 67 seconds (interquartile range [IQR] 46-105 seconds); for standard mammography, 16 seconds (IQR, 10-29 seconds).Conclusions: Breast cancer detection, recall for assessment, and screen reading time were each higher for tomosynthesis than for standard mammography. Our preliminary findings could form the basis of a large scale comparative evaluation of tomosynthesis and standard mammography for breast screening in Australia.Trial Registration: Australian New Zealand Clinical Trials Registry, ACTRN12617000947303. [ABSTRACT FROM AUTHOR]- Published
- 2019
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3. Agreement between digital breast tomosynthesis and pathologic tumour size for staging breast cancer, and comparison with standard mammography.
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Marinovich, M. Luke, Bernardi, Daniela, Macaskill, Petra, Ventriglia, Anna, Sabatino, Vincenzo, and Houssami, Nehmat
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TOMOSYNTHESIS ,BREAST cancer ,MAMMOGRAMS - Abstract
Abstract Purpose Tomosynthesis is proposed to improve breast cancer assessment and staging. We compared tomosynthesis and mammography in estimating the size of newly-diagnosed breast cancers. Methods All pathologically-confirmed cancers detected in the STORM-2 trial (90 cancers, 85 women) were retrospectively measured on tomosynthesis by two independent readers. One reader also measured cancers on mammography. Relative mean differences (MDs) and 95% limits of agreement (LOA) with pathology were estimated for tomosynthesis and mammography within a single reader (Analysis 1) and between two readers (Analysis 2). Results Where cancers were detected and hence measured by both tests, tomosynthesis overestimated pathologic size relative to mammography (Analysis 1: MD 5% versus 1%, Analysis 2: 7% versus 3%; P = 0.10 both analyses). There was similar, large measurement variability for both tests (LOA range: −60% to +166%). Overestimation by tomosynthesis was attributable to the subgroup with dense breasts (MDs = 12–13% versus 4% for mammography). There was low average bias for both tests in the low-density subgroup (MDs = 0–4%). LOA were larger in dense breasts for both tomosynthesis and mammography (P ≤ 0.02 all comparisons). Cancers detected only by tomosynthesis were more frequently in dense breasts (60–68%): for those tumours size was estimated with increased measurement variability (LOA ranging from −75% to +293%). Conclusions On average, tomosynthesis overestimates pathologic tumour size in women with dense breasts; that difference is more likely to impact management in women with larger tumours. The main advantage of tomosynthesis appears to be detecting mammographically-occult cancers; however tomosynthesis less accurately measured those cancers in dense breasts (large measurement variability). Highlights • Tumour size was overestimated by tomosynthesis relative to mammography. • Overestimation was attributable to the subgroup with high breast density. • There was low average bias for both tests in the low-density subgroup. • Cancers detected only by tomosynthesis were measured with large variability. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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4. Interval breast cancers in the ‘screening with tomosynthesis or standard mammography’ (STORM) population-based trial.
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Houssami, Nehmat, Bernardi, Daniela, Caumo, Francesca, Brunelli, Silvia, Fantò, Carmine, Valentini, Marvi, Romanucci, Giovanna, Gentilini, Maria A., Zorzi, Manuel, and Macaskill, Petra
- Subjects
BREAST cancer ,BREAST exams ,TOMOSYNTHESIS ,MAMMOGRAMS ,DIGITAL mammography - Abstract
Background & methods The prospective ‘ s creening with t omosynthesis or standard m ammography’ (STORM) trial recruited women participating in biennial breast screening in Italy (2011–2012), and compared sequential screen-readings based on 2D-mammography alone or based on tomosynthesis (integrated 2D/3D-mammography). The STORM trial showed that tomosynthesis screen-reading significantly increased breast cancer detection compared to 2D-mammography alone. The present study completes reporting of the trial by examining interval breast cancers ascertained at two year follow-up. Results 9 interval breast cancers were identified; the estimated interval cancer rate was 1.23/1000 screens [9/7292] (95%CI 0.56 to 2.34) or 1.24/1000 negative screens [9/7235] (95%CI 0.57 to 2.36). In concurrently screened women who attended the same screening services and received 2D-mammography, interval cancer rate was 1.60/1000 screens [40/25,058] (95% CI 1.14 to 2.17) or 1.61/1000 negative screens [40/24,922] (95% CI 1.15 to 2.18). Estimated screening sensitivity for the STORM trial was 85.5% [59/69] (95%CI 75.0%–92.8%), and that for 2D-mammography screening was 77.3% [136/176] (95%CI 70.4%–83.2%). Conclusion Interval breast cancer rate amongst screening participants in the STORM trial was marginally lower (and screening sensitivity higher) than estimates amongst 2D-screened women; these findings should be interpreted with caution given the small number of interval cases and the sample size of the trial. Much larger screening studies, or pooled analyses, are required to examine interval cancer rates arising after breast tomosynthesis screening versus digital mammography screening. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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5. Pilot trial of digital breast tomosynthesis (3D mammography) for population‐based screening in BreastScreen Victoria
- Author
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Houssami, Nehmat, Lockie, Darren, Clemson, Michelle, Pridmore, Vicki, Taylor, David, Marr, Georgina, Evans, Jill, and Macaskill, Petra
- Abstract
To estimate detection measures for tomosynthesis and standard mammography; to assess the feasibility of using tomosynthesis in population‐based screening for breast cancer. Prospective pilot trial comparing tomosynthesis (with synthesised 2D images) and standard mammography screening of women attending Maroondah BreastScreen, a BreastScreen Victoria service in the eastern suburbs of Melbourne. Women at least 40 years of age who presented for routine breast screening between 18 August 2017 and 8 November 2018. Cancer detection rate (CDR); proportion of screens that led to recall for further assessment. 5018 tomosynthesis and 5166 standard mammography screens were undertaken in 10 146 women; 508 women (5.0% of screens) opted not to undergo tomosynthesis screening. With tomosynthesis, 49 cancers (40 invasive, 9 in situ) were detected (CDR, 9.8 [95% CI, 7.2–13] per 1000 screens); with standard mammography, 34 cancers (30 invasive, 4 in situ) were detected (CDR, 6.6 [95% CI, 4.6–9.2] per 1000 screens). The estimated difference in CDRwas 3.2 more detections (95% CI, –0.32 to 6.8) per 1000 screens with tomosynthesis; the difference was greater for repeat screens and for women aged 60 years or more. The recall rate was greater for tomosynthesis (4.2%; 95% CI, 3.6–4.8%) than standard mammography (3.0%; 95% CI, 2.6–3.5%; estimated difference, 1.2%; 95% CI, 0.46–1.9%). The median screen reading time for tomosynthesis was 67 seconds (interquartile range [IQR] 46–105 seconds); for standard mammography, 16 seconds (IQR, 10–29 seconds). Breast cancer detection, recall for assessment, and screen reading time were each higher for tomosynthesis than for standard mammography. Our preliminary findings could form the basis of a large scale comparative evaluation of tomosynthesis and standard mammography for breast screening in Australia. Australian New Zealand Clinical Trials Registry, ACTRN12617000947303.
- Published
- 2019
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6. The Validity of Drug Effects on Proteinuria, Albuminuria, Serum Creatinine, and Estimated GFR as Surrogate End Points for ESKD: A Systematic Review
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Palmer, Suetonia C., Ruospo, Marinella, Teixeira-Pinto, Armando, Craig, Jonathan C., Macaskill, Petra, and Strippoli, Giovanni F.M.
- Abstract
Proteinuria, albuminuria, and serum creatinine level are widely used as surrogate end point measures of end-stage kidney disease (ESKD). We evaluated the correlation between antihypertensive drug effects on surrogate renal end points and ESKD.
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- 2018
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7. Elevated Liver Enzymes and Mortality in Older Individuals
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Mahady, Suzanne E., Wong, Germaine, Turner, Robin M., Mitchell, Paul, Macaskill, Petra, Craig, Jonathan C., and George, Jacob
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- 2017
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8. Diagnostic accuracy of the Ottawa Ankle and Midfoot Rules: a systematic review with meta-analysis
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Beckenkamp, Paula R, Lin, Chung-Wei Christine, Macaskill, Petra, Michaleff, Zoe A, Maher, Chris G, and Moseley, Anne M
- Abstract
ObjectiveTo review the diagnostic accuracy of the Ottawa Ankle and Midfoot Rules and explore if clinical features and/or methodological quality of the study influence diagnostic accuracy estimates.DesignSystematic review with meta-analysis.Data sourcesMEDLINE, EMBASE, CINAHL, SPORTDiscus and Cochrane Library.Eligibility criteria for selecting studiesPrimary diagnostic studies reporting the accuracy of the Rules in people with ankle and/or midfoot injury were retrieved. Diagnostic accuracy estimates, overall and for subgroups (patient’s age, profession of the assessor and setting of application), were made. Sensitivity analyses included studies with a low risk of bias and studies where all patients received radiographs.Results66 studies were included. Ankle and Midfoot Rules presented similar accuracies, which were homogeneous and high for sensitivity and negative likelihood ratios and poor and heterogeneous for specificity and positive likelihood ratios (mean, 95% CI pooled sensitivity of Ankle Rules: 99.4%, 97.9% to 99.8%; specificity: 35.3%, 28.8% to 42.3%). Sensitivity of the Ankle Rules was higher in adults than in children, but the profession of the assessor did not appear to influence accuracy. Specificity was higher for Midfoot than for Ankle Rules. There were not enough studies to allow comparison according to setting of application. Studies with a low risk of bias and where all patients received radiographs provided lower accuracy estimates. Specificity heterogeneity was not explained by assessor training, use of imaging in all patients and low risk of bias.ConclusionsStudy features and the methodological quality influence estimates of the diagnostic accuracy of the Ottawa Ankle and Midfoot Rules.
- Published
- 2017
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9. Radiologists' interpretive efficiency and variability in true- and false-positive detection when screen-reading with tomosynthesis (3D-mammography) relative to standard mammography in population screening.
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Svahn, Tony M., Macaskill, Petra, and Houssami, Nehmat
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TOMOSYNTHESIS ,MEDICAL imaging systems ,THREE-dimensional imaging ,BREAST cancer diagnosis ,RADIOLOGISTS ,LOGISTIC regression analysis - Abstract
We examined interpretive efficiency and variability in true- and false-positive detection (TP, FP) for radiologists screen-reading with digital breast tomosynthesis as adjunct to full-field digital mammography (2D/3D) relative to 2D alone in population-based screening studies. A systematic literature search was performed to identify screening studies that provided radiologist-specific data for TP and FP detection. Radiologist interpretive efficiency (trade-off between TPs and FPs) was calculated using the FP:TP ratio which expresses the number of FP recalls for each screen-detected breast cancer. We modeled a pooled FP:TP ratio to assess variability in radiologists' interpretive efficiency at study-level using random effects logistic regression. FP:TP ratio improved (ratio decreased) for 2D/3D screen-reading (relative to 2D) for a majority of radiologists (18 of 22) across all studies. Variability in radiologists' FP:TP ratio was consistently lower in all studies for 2D/3D screen-reading, as suggested by lower variance in ratios. Study-level pooled FP:TP ratio for 2D- and 2D/3D-mammography respectively, were 5.96 (95%CI: 4.08 to 8.72) and 3.17 (95%CI: 2.25 to 4.47) for the STORM trial; 10.25 (95%CI: 6.42 to 16.35) and 7.07 (95%CI: 4.99 to 10.02) for the Oslo trial; and 20.84 (95%CI: 13.95 to 31.12) and 8.37 (95%CI: 5.87 to 11.93) for the Houston study. This transfers into study-level improved interpretative efficiencies of 48%, 30% and 55%, respectively, for 2D/3D screen-reading (relative to 2D). In summary, study-level FP:TP trade-off improved using 2D/3D-mammography for all studies, which was also seen for most individual radiologists. There was variability in the FP:TP trade-off between readers and studies for 2D-as well as for 2D/3D-interpretations but variability in radiologists' interpretive efficiency was relatively lower using 2D/3D-mammography. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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10. An Individual Person Data Meta-Analysis of Preoperative Magnetic Resonance Imaging and Breast Cancer Recurrence.
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Houssami, Nehmat, Turner, Robin, Macaskill, Petra, Turnbull, Lindsay W., McCready, David R., Tuttle, Todd M., Vapiwala, Neha, and Solin, Lawrence J.
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- 2014
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11. Incremental effect from integrating 3D-mammography (tomosynthesis) with 2D-mammography: Increased breast cancer detection evident for screening centres in a population-based trial.
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Caumo, Francesca, Bernardi, Daniela, Ciatto, Stefano, Macaskill, Petra, Pellegrini, Marco, Brunelli, Silvia, Tuttobene, Paola, Bricolo, Paola, Fantò, Carmine, Valentini, Marvi, Montemezzi, Stefania, and Houssami, Nehmat
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BREAST cancer diagnosis ,MAMMOGRAMS ,MEDICAL imaging systems ,THREE-dimensional imaging ,BREAST imaging ,EARLY detection of cancer ,CANCER in women - Abstract
Abstract: Background & objectives: Three-dimensional (3D)-mammography (tomosynthesis) may improve breast cancer detection. We examined centre-specific effect of integrated 2D/3D mammography based on the STORM (screening with tomosynthesis or standard mammography) trial. Methods: Asymptomatic women who attended population-based screening through Trento and Verona screening centres were recruited into STORM, a prospective comparison of screen-reading in two sequential phases: 2D-mammography only and integrated 2D/3D mammography. Outcomes were the number and rates of detected cancers and of false positive recalls (FPR), and incremental cancer detection rate (CDR). Paired binary data were compared using Mc Nemar's test. Results: Of 33 cancers detected in Trento, 21 were detected at both 2D and 2D/3D screening, 12 cancers were detected only with integrated 2D/3D screening compared with none detected at 2D-only screening (P < 0.001). Of the 26 cancers detected in Verona, 18 were detected at both 2D and 2D/3D screening, 8 cancers were detected only with integrated 2D/3D screening compared with none detected at 2D-only screening (P = 0.008). There were no differences between centres in baseline CDR, and incremental CDR attributable to 3D-mammography was similar for Trento (2.8/1000 screens) and for Verona (2.6/1000 screens). Trento had 239 FPR (5.7% of screens): 103 FPR at both screen-readings, 93 FPR only at 2D-mammography compared with 43 FPR only at 2D/3D-mammography (p < 0.001). Verona had 156 FPR (5.2% of screens): 78 FPR at both screen-readings, 48 FPR only at 2D-mammography compared with 30 FPR only at 2D/3D-mammography (p = 0.054). Estimated reduction in FPR proportion had recall been conditional to 2D/3D-mammography-positivity differed between centres (21.0% versus 11.5%; P = 0.02). Conclusion: Integrated 2D/3D-mammography significantly increased cancer detection for both screening services; potential reduction in FPR is likely to differ between centres with those experiencing relatively higher FPR most likely to benefit from 2D/3D-mammography screening. [Copyright &y& Elsevier]
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- 2014
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12. Association of Drug Effects on Serum Parathyroid Hormone, Phosphorus, and Calcium Levels With Mortality in CKD: A Meta-analysis
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Palmer, Suetonia C., Teixeira-Pinto, Armando, Saglimbene, Valeria, Craig, Jonathan C., Macaskill, Petra, Tonelli, Marcello, de Berardis, Giorgia, Ruospo, Marinella, and Strippoli, Giovanni F.M.
- Abstract
Serum parathyroid hormone (PTH), phosphorus, and calcium levels are surrogate outcomes that are central to the evaluation of drug treatments in chronic kidney disease (CKD). This systematic review evaluates the evidence for the correlation between drug effects on biochemical (PTH, phosphorus, and calcium) and all-cause and cardiovascular mortality end points in adults with CKD.
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- 2015
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13. Cancer-Specific and All-Cause Mortality in Kidney Transplant Recipients With and Without Previous Cancer
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Viecelli, Andrea K., Lim, Wai H., Macaskill, Petra, Chapman, Jeremy R., Craig, Jonathan C., Clayton, Philip, Cohney, Solomon, Carroll, Robert, and Wong, Germaine
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Using data from the ANZDATA registry, the authors demonstrate that cancer-specific and all-cause mortality are similar in patients who develop a first cancer after kidney transplantation and in the rare patient with a prior cancer history whether they experience cancer recurrence or a second primary cancer.
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- 2015
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14. Lack of Accuracy of Body Temperature for Detecting Serious Bacterial Infection in Febrile Episodes
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De, Sukanya, Williams, Gabrielle J., Teixeira-Pinto, Armando, Macaskill, Petra, McCaskill, Mary, Isaacs, David, and Craig, Jonathan C.
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Supplemental Digital Content is available in the text.
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- 2015
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15. Monitoring initial response to Angiotensin-converting enzyme inhibitor-based regimens: an individual patient data meta-analysis from randomized, placebo-controlled trials.
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Bell, Katy J.L., Hayen, Andrew, Macaskill, Petra, Craig, Jonathan C., Neal, Bruce C., Fox, Kim M., Remme, Willem J., Asselbergs, Folkert W., van Gilst, Wiek H., MacMahon, Stephen, Remuzzi, Giuseppe, Ruggenenti, Piero, Teo, Koon K., and Irwig, Les
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Most clinicians monitor blood pressure to estimate a patient's response to blood pressure-lowering therapy. However, the apparent change may not actually reflect the effect of the treatment, because a person's blood pressure varies considerably even without the administration of drug therapy. We estimated random background within-person variation, apparent between-person variation, and true between-person variation in blood pressure response to angiotensin-converting enzyme inhibitors after 3 months. We used meta-analytic mixed models to analyze individual patient data from 28 281 participants in 7 randomized, controlled trials from the Blood Pressure Lowering Trialists Collaboration. The apparent between-person variation in response was large, with SDs for change in systolic blood pressure/diastolic blood pressure of 15.2/8.5 mm Hg. Within-person variation was also large, with SDs for change in systolic blood pressure/diastolic blood pressure of 14.9/8.45 mm Hg. The true between-person variation in response was small, with SDs for change in systolic blood pressure/diastolic blood pressure of 2.6/1.0 mm Hg. The proportion of the apparent between-person variation in response that was attributed to true between-person variation was only 3% for systolic blood pressure and 1% for diastolic blood pressure. In conclusion, most of the apparent variation in response is not because of true variation but is a consequence of background within-person fluctuation in day-to-day blood pressure levels. Instead of monitoring an individual's blood pressure response, a better approach may be to simply assume the mean treatment effect. [ABSTRACT FROM AUTHOR]
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- 2010
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16. Population Prevalence and Correlates of Stages of Change in Physical Activity.
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Booth, Michael L., Macaskill, Petra, Owen, Neville, Oldenburg, Brian, Marcus, Bess H., and Bauman, Adrian
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Stages of change for exercise, sociodemographic variables, and beliefs about the health benefits of exercise were obtained for a representative sample of Australian adults (N = 4404). Logistic regression analysis was used to examine the relationship between exercise stage of change and sociodemographic variables and beliefs about the benefits of exercise. Thirteen percent of respondents stated that they did not exercise and did not intend to start; 10% stated that they did not exercise but were thinking of starting; 16% stated that they exercise occasionally and were not thinking of doing more; 23% stated that they exercised occasionally and were thinking of doing more; and 38% stated that they exercised regularly and intended to continue. Intention to do more exercise generally decreased with increasing age, but increased with level of education. An increased frequency of exercise and an intention to do more exercise was associated with the belief that exercise would help to prevent heart disease and with a higher level of education. The results provide a useful profile of the exercise habits (and intention to change those habits) of population subgroups. Public communication campaigns on the benefits of physical activity should focus particularly on those who do not intend to exercise, older adults, and the less well educated. [ABSTRACT FROM PUBLISHER]
- Published
- 1993
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17. Population prevalence and correlates of stages of change in physical activity.
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Booth, Michael L. and Macaskill, Petra
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Reports on a study that examined the relationship between exercise stage of change and sociodemographic variables and beliefs about the benefits of exercise. Representative sample of Australian adults; Methodology of the study; Logistic regression analysis; Profile of the exercise habits of population subgroups.
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- 1993
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18. Use of randomised trials to decide when to monitor response to new treatment
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Bell, Katy J L, Irwig, Les, Craig, Jonathan C, and Macaskill, Petra
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- 2008
19. Effect of study design and quality on unsatisfactory rates, cytology classifications, and accuracy in liquid-based versus conventional cervical cytology: a systematic review
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Davey, Elizabeth, Barratt, Alexandra, Irwig, Les, Chan, Siew F, Macaskill, Petra, Mannes, Patricia, and Saville, A Marion
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- 2006
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20. Risk factors for HIV infection in a gynaeco–obstetric population in Vietnam - a case-control study
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Tran, Thi Thu Ha, Mulhall, Brian P., Macaskill, Petra, and Nguyen, Thanh Quang
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Background: Vietnam has an emerging HIV epidemic, particularly in male drug injectors. Data on HIV infections in women in the general population, and their risk factors, are scanty. Methods: A case-control study was performed in a large gynaeco?obstetric hospital in Haiphong city in 1998?2001. The sample was 22000 attendees. The medical records of 58 HIV-seropositive cases were compared with 422 randomly chosen HIV-seronegative controls for potential risk factors. Results: A multivariate analysis found that HIV infection was associated with young age, past/current history of sexually transmitted infections (STI) and being unemployed. Patients aged 21?30 years were 10-fold less likely to be infected than women aged <20 years (OR 0.11, 95%CI 0.04?0.33). Women with a past/current history of STI had over 20 times the risk of those who did not (95% CI 6.7?62.3). Unemployed women had at least twice the risk of infection of any other occupational group. Conclusions: We have identified risk factors in women that have not been highlighted previously in Vietnam. Our study suggests that all antenatal women, especially those who are young or unemployed (or, with a current/past history of STI), should be offered free HIV tests, counselling and management.
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- 2005
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21. Assessing the gain in diagnostic performance when combining two diagnostic tests
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Macaskill, Petra, Walter, Stephen D., Irwig, Les, and Franco, Eduardo L.
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Combining dichotomous (or dichotomized) results of two diagnostic tests will result in a trade‐off in sensitivity and specificity of the combined test relative to the component tests. Because of this inherent trade‐off, likelihood ratios provide a clinically relevant means of comparing the combined test with one of its components. The likelihood ratios depend on both sensitivity and specificity and hence take into account the trade‐off between them. A graphical approach is used to assess whether the combined test is superior to a component test, or vice versa. Asymptotic standard errors are derived for comparing likelihood ratios when a paired study design is used. The trade‐off in the expected number of additional true positive and false positive results (or true negative and false negative results) is used as the basis for deciding whether to use tests in combination when neither the combined nor a component test shows superior test performance based on their likelihood ratios. These methods are illustrated with an example that considers the combined use of Pap and HPV testing. Copyright © 2002 John Wiley & Sons, Ltd.
- Published
- 2002
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22. Epidemiology of physical activity participation among New South Wales school students
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Booth, Michael L., Okely, Anthony D., Chey, Tien, Bauman, Adrian E., and Macaskill, Petra
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Objective: To examine the prevalence and socio‐demographic distribution of physical activity among New South Wales school students in Years 8 and 10. Methods: Cross‐sectional survey of 2,026 randomly selected NSW high school students in 1997. The survey participants self‐reported their physical activity participation during a normal week in summer and winter school terms. Results: During summer school terms, 80.9% and 85.9% of Year 8 and Year 10 boys, respectively, and 80.8% and 77.7% of Year 8 and Year 10 girls, respectively, were adequately active. During winter school terms, 75.6% and 84.0% of Year 8 and Year 10 boys, respectively, and 69.4% and 66.0% of Year 8 and Year 10 girls, respectively, were adequately active. The associations between socio‐economic status, urban/rural place of residence and physical activity participation were neither strong nor consistent. There were complex relationships between physical activity participation and cultural background among boys, and large differences between different cultural groups of girls and large declines in participation from Year 8 to Year 10 among girls. Conclusions: Although the majority of boys and girls are adequately active, it is clear that a smaller proportion of girls than boys are vigorously active, particularly during winter. There were no clear differences across tertiles of SES or place of residence, but there were significant differences between girls from different cultural backgrounds. Implications: Efforts to increase the proportion of young people who are vigorously active should emphasise the needs and interests of girls, particularly those from Middle‐Eastern and Asian cultural backgrounds.
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- 2002
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23. Epidemiology of physical activity participation among New South Wales school students
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Booth, Michael L., Okely, Anthony D., Chey, Tien, Bauman, Adrian E., and Macaskill, Petra
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Objective: To examine the prevalence and socio‐demographic distribution of physical activity among New South Wales school students in Years 8 and 10.
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- 2002
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24. Analytic methods for comparing two dichotomous screening or diagnostic tests applied to two populations of differing disease prevalence when individuals negative on both tests are unverified
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Berry, Geoffrey, Smith, Catherine L., Macaskill, Petra, and Irwig, Les
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Two dichotomous screening tests may be compared by applying both tests to all members of a sampled population. For individuals with a positive result on either test the disease status may be verified by a reference standard, but for individuals negative on both tests the disease status may be unverified because the probability of disease is so low that further investigation is costly, unacceptable and perhaps unethical. If the tests have been applied to samples from two populations which have different disease prevalences then unbiased estimates of the true positive and false positive rates of each test, the prevalences in the two populations, and two parameters representing dependence between the two tests can be estimated using maximum likelihood methods. The methods are based on the assumption that the sensitivities and specificities of the two tests, and the dependencies between the tests, are independent of prevalence. A test of goodness of fit provides a test of this. Copyright © 2002 John Wiley & Sons, Ltd.
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- 2002
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25. Sensitivity and specificity of tests to detect eye disease in an older population
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Ivers, Rebecca Q, Macaskill, Petra, Cumming, Robert G, and Mitchell, Paul
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To compare the ability of tests of visual function to detect the presence of eye disease.
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- 2001
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26. A comparison of methods to detect publication bias in meta-analysis
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Macaskill, Petra, Walter, Stephen D., and Irwig, Les
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Meta-analyses are subject to bias for many of reasons, including publication bias. Asymmetry in a funnel plot of study size against treatment effect is often used to identify such bias. We compare the performance of three simple methods of testing for bias: the rank correlation method; a simple linear regression of the standardized estimate of treatment effect on the precision of the estimate; and a regression of the treatment effect on sample size. The tests are applied to simulated meta-analyses in the presence and absence of publication bias. Both one-sided and two-sided censoring of studies based on statistical significance was used. The results indicate that none of the tests performs consistently well. Test performance varied with the magnitude of the true treatment effect, distribution of study size and whether a one- or two-tailed significance test was employed. Overall, the power of the tests was low when the number of studies per meta-analysis was close to that often observed in practice. Tests that showed the highest power also had type I error rates higher than the nominal level. Based on the empirical type I error rates, a regression of treatment effect on sample size, weighted by the inverse of the variance of the logit of the pooled proportion (using the marginal total) is the preferred method. Copyright © 2001 John Wiley & Sons, Ltd.
- Published
- 2001
27. A comparison of methods to detect publication bias in meta‐analysis
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Macaskill, Petra, Walter, Stephen D., and Irwig, Les
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Meta‐analyses are subject to bias for many of reasons, including publication bias. Asymmetry in a funnel plot of study size against treatment effect is often used to identify such bias. We compare the performance of three simple methods of testing for bias: the rank correlation method; a simple linear regression of the standardized estimate of treatment effect on the precision of the estimate; and a regression of the treatment effect on sample size. The tests are applied to simulated meta‐analyses in the presence and absence of publication bias. Both one‐sided and two‐sided censoring of studies based on statistical significance was used. The results indicate that none of the tests performs consistently well. Test performance varied with the magnitude of the true treatment effect, distribution of study size and whether a one‐ or two‐tailed significance test was employed. Overall, the power of the tests was low when the number of studies per meta‐analysis was close to that often observed in practice. Tests that showed the highest power also had type I error rates higher than the nominal level. Based on the empirical type I error rates, a regression of treatment effect on sample size, weighted by the inverse of the variance of the logit of the pooled proportion (using the marginal total) is the preferred method. Copyright © 2001 John Wiley & Sons, Ltd.
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- 2001
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28. Multiple sclerosis in Australia: prognostic factors
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Hammond, Simon R., McLeod, James G., Macaskill, Petra, and English, Dallas R.
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In order to determine the influence of age of onset, sex, onset symptoms, clinical course and interval from onset to first relapse on the subsequent outcome of multiple sclerosis (MS), data from 2934 cases of MS documented in a large population based study undertaken in Australia have been analysed. Disability on prevalence day (30 June 1981) was defined on the Kurtzke disability scale as mild (DSS 03), moderate (DSS 46) and severe (DSS 79). Prognostic factors associated with mild vs moderate/severe, and moderate vs severe disability on prevalence day were identified by logistic regression analysis. A worse prognosis was significantly associated with older age of onset, progressive disease course, onset symptoms that were multiple, pyramidal or cerebellar, and a short interval between onset and first relapse. Copyright 2000 Harcourt Publishers Ltd
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- 2000
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29. Mastery of fundamental motor skills among new south wales school students: Prevalence and sociodemographic distribution
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Booth, Michael L, Okely, Tony, McLellan, Lyndall, Phongsavan, Philayrath, Macaskill, Petra, Patterson, John, Wright, Jan, and Holland, Bernie
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- 1999
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30. Global Burden of Disease and Injury Due to Occupational Factors
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Leigh, James, Macaskill, Petra, Kuosma, Eeva, and Mandryk, John
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We made estimates of absolute morbidity and mortality due to occupational factors for the world using all available published data as of 1994, and, where no data were available, applying the most appropriate (in terms of similar economy, race, and environment) age-/sex-/diagnosis-specific incidence and mortality rates to known working population distributions. We report results according to economic groupings determined by the World Bank (World Development Report, 1993) and disease and injury groupings according to The Global Burden of Disease project (1997). This was part of a larger study that estimated the total global disease burden. We present aggregate results and analyses by region and disease. We estimate that approximately 100,000,000 occupational injuries (100,000 deaths) and 11,000,000 occupational diseases (700,000 deaths) occur in the world each year. We regard these as very conservative estimates which, although unavoidably crude, can nevertheless provide a basis for health priority planning at global level.
- Published
- 1999
31. Test accuracy and potential sources of bias in diagnostic test evaluation.
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Bell, Katy JL, Macaskill, Petra, Loy, Clement, Attia, John R, and Jones, Michael P
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Understanding how to interpret diagnostic test accuracy studies is a key skill that health practitioners need to develop in order to undertake evidence-based practice.[1] In this article we guide the reader through how to interpret a diagnostic test accuracy study, including the potential for bias. Typically, tests with higher sensitivity have lower specificity and vice versa, so the main purpose of applying the test must be considered when deciding on choice of test.[5] A highly specific test (Sp) returning a positive result (P) effectively rules in the diagnosis (SpPin); for example, meningococcal rash in meningococcal meningitis. Although we have focused on single diagnostic test accuracy studies so far, ideally we should seek out systematic reviews of the test we are interested in, so that we have estimates of test accuracy based on the totality of the evidence. When the spectrum of disease in the study population does not represent the intended population where the test will be used, test accuracy estimates may not be applicable. [Extracted from the article]
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- 2020
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32. Methods of the NSW schools fitness and physical activity survey, 1997
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Booth, Michael L., Macaskill, Petra, Phongsavan, Philayrath, McLellan, Lyndall, and Okely, Tony
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- 1998
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33. Population Prevalence and Correlates of Stages of Change in Physical Activity
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Booth, Michael L., Macaskill, Petra, Owen, Neville, Oldenburg, Brian, Marcus, Bess H., and Bauman, Adrian
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Stages of change for exercise, sociodemographic variables, and beliefs about the health benefits of exercise were obtained for a representative sample of Australian adults (N = 4404). Logistic regression analysis was used to examine the relationship between exercise stage of change and sociodemographic variables and beliefs about the benefits of exercise. Thirteen percent of respondents stated that they did not exercise and did not intend to start; 10% stated that they did not exercise but were thinking of starting; 16% stated that they exercise occasionally and were not thinking of doing more; 23% stated that they exercised occasionally and were thinking of doing more; and 38% stated that they exercised regularly and intended to continue. Intention to do more exercise generally decreased with increasing age, but increased with level of education. An increased frequency of exercise and an intention to do more exercise was associated with the belief that exercise would help to prevent heart disease and with a higher level of education. The results provide a useful profile of the exercise habits (and intention to change those habits) of population subgroups. Public communication campaigns on the benefits of physical activity should focus particularly on those who do not intend to exercise, older adults, and the less well educated.
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- 1993
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34. Who has Pap smears in New South Wales? Patterns of screening across sociodemographic groups
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Shelley, Julia M., Irwig, Les M., Simpson, Judy M., and Macaskill, Petra
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The aim of this study was to determine whether Pap smear screening at adequate intervals is associated with area of residence, frequency of consultations with a general practitioner, socioeconomic status and non‐English‐speaking background. A representative 10 per cent sample of women from New South Wales and the Australian Capital Territory, aged 25 to 69 years and registered with the Health Insurance Commission (Medicare) (N= 155 281) was used to obtain age, postcode, frequency of Pap smears and frequency of consultations with general practitioners in the three‐year period from February 1985 to January 1988. Census data for each postcode area were used as an indicator of other sociodemographic characteristics. Age‐specific screening rates did not vary between Sydney, Newcastle/Wollongong, Canberra, and nonmetropolitan areas. In all age groups, having had a smear was most strongly associated with the frequency with which a woman consulted a general practitioner. Women who visited a general practitioner at least four times a year on average were about twice as likely to have had a recent Pap smear as those who averaged less than one visit per year. Screening rates were lowest among women living in areas with the most non‐English‐speakers and the lowest socioeconomic status. Sociodemographic factors and health service usage patterns influence the proportion of women who are currently being screened. Evaluation of interventions to improve Pap smear screening rates should consider whether the percentage of women screened increases overall, and also whether the imbalances in screening rates between different groups are diminishing.
- Published
- 1994
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35. Health risks and behaviour of out–of–school 16–year–olds in New South Wales
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Tresidder, Julia, Macaskill, Petra, Bennett, David, and Nutbeam, Don
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Abstract: This study describes the health risks and health behaviour of a sample of 283 out–of–school 16–year–olds in New South Wales. We sampled study participants through the Commonwealth Employment Service offices in 1994 using a multistage sampling procedure. Of those surveyed, 129 responded to a letter inviting them to participate and 154 were recruited opportunistically. This paper describes the study methods and results for self–reported binge drinking, weekly use of tobacco and marijuana, sexual abuse, physical abuse, drink–driving, violence, and use of health services, by sex and method of recruitment. High rates of substance use were observed. Reported substance use in the out–of–school group was consistently higher than for 16–year–olds in school, except for binge drinking for girls recruited by letter. Of the out–of–school group, 34 per cent reported weekly use of tobacco, marijuana and also binge drinking. Boys were more likely to report drink–driving than girls (28 per cent and 13 per cent respectively). Having been in trouble with police ranged from 32 per cent for girls recruited by letter to 75 per cent for boys recruited opportunistically. A high proportion of girls reported sexual abuse (34 per cent of the ‘letter’ group and 41 per cent of the ‘opportunistic’ group). Overall, 87 per cent of respondents had used health services in the previous year. The results indicate that this is a disadvantaged group of young people who are an important target for health service provision and interventions.
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- 1997
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36. Changes in reported drug prevalence among New South Wales secondary school students, 1983 to 1989
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Donnelly, Neil, Oldenburg, Brian, Quine, Susan, Macaskill, Petra, Flaherty, Bruce, Spooner, Catherine, and Lyle, David
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Three drug use surveys employing a standardised questionnaire format and sampling procedure were conducted on samples of New South Wales school students in 1983, 1986 and 1989. Alcohol and tobacco were the most frequently used substances across the surveys, with rates of use of illicit substances being considerably lower. Declines in the prevalence of alcohol, tobacco and stimulant use were found between 1983 and 1986 and between 1986 and 1989 for both males and females. Rates of use of inhalants, sedatives, hallucinogens and narcotics declined between 1983 and 1986, but remained unchanged between the 1986 and 1989 samples. Cannabis use declined significantly among females between 1983 and 1989, but not among males. Possible reasons for the general decline in drug use over the six‐year period are discussed.
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- 1992
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37. Prevalences and perceptions of licit and illicit drugs among New South Wales secondary school students, 1989
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Donnelly, Neil, Quine, Susan, Oldenburg, Brian, Macaskill, Petra, Lyle, David, Flaherty, Bruce, and Spooner, Catherine
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This paper presents findings on drug prevalences for licit and illicit drugs among New South Wales secondary school students (n= 3753) in late 1989. It also considers the accuracy of students' perceptions of the drug causing the most and fewest drug‐related deaths. Data were analysed by age and gender, using logistic regression for the prevalence data. Findings indicate that licit drugs (tobacco, alcohol and analgesics) were the most frequently and widely used. Rates for illicit drugs were low, although there was some degree of experimental use of cannabis which increased amongst older males. Perceptions were found to be inaccurate in emphasising the dangers of the illicit drug heroin over those of the licit drugs tobacco and alcohol. Reasons for these findings are discussed, and more in‐depth research recommended into the relationship between drug prevalences and perceptions for different age groups, and its relevance for planning drug prevention initiatives.
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- 1992
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38. Health risks and behaviour of out-of-school 16-year-olds in New South Wales
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Tresidder, Julia, Macaskill, Petra, Bennett, David, and Nutbeam, Don
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This study describes the health risks and health behaviour of a sample of 283 out-of-school 16-year-olds in New South Wales. We sampled study participants through the Commonwealth Employment Service offices in 1994 using a multistage sampling procedure. Of those surveyed, 129 responded to a letter inviting them to participate and 154 were recruited opportunistically. This paper describes the study methods and results for self-reported binge drinking, weekly use of tobacco and marijuana, sexual abuse, physical abuse, drink-driving, violence, and use of health services, by sex and method of recruitment. High rates of substance use were observed. Reported substance use in the out-of-school group was consistently higher than for 16-year-olds in school, except for binge drinking for girls recruited by letter. Of the out-of-school group, 34 per cent reported weekly use of tobacco, marijuana and also binge drinking. Boys were more likely to report drink-driving than girls (28 per cent and 13 per cent respectively). Having been in trouble with police ranged from 32 per cent for girls recruited by letter to 75 per cent for boys recruited opportunistically. A high proportion of girls reported sexual abuse (34 per cent of the ‘letter’ group and 41 per cent of the ‘opportunistic’ group). Overall, 87 per cent of respondents had used health services in the previous year. The results indicate that this is a disadvantaged group of young people who are an important target for health service provision and interventions.
- Published
- 1997
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39. Standard deviation and standard error: interpretation, usage and reporting.
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Macaskill, Petra
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The article focuses on standard deviation and standard error and their interpretation, usage and reporting.
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- 2018
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40. Preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts): checklist, explanation, and elaboration
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Cohen, Jérémie F, Deeks, Jonathan J, Hooft, Lotty, Salameh, Jean-Paul, Korevaar, Danie¨l A, Gatsonis, Constantine, Hopewell, Sally, Hunt, Harriet A, Hyde, Chris J, Leeflang, Mariska M, Macaskill, Petra, McGrath, Trevor A, Moher, David, Reitsma, Johannes B, Rutjes, Anne W S, Takwoingi, Yemisi, Tonelli, Marcello, Whiting, Penny, Willis, Brian H, Thombs, Brett, Bossuyt, Patrick M, and McInnes, Matthew D F
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- 2021
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41. Test accuracy and potential sources of bias in diagnostic test evaluation
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Bell, Katy JL, Macaskill, Petra, Loy, Clement, Attia, John R, and Jones, Michael P
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- 2020
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42. Diagnostic Accuracy of Noninvasive Fibrosis Scores in a Population of Individuals With a Low Prevalence of Fibrosis.
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Mahady, Suzanne E., Macaskill, Petra, Craig, Jonathan C., Wong, Grace L.H., Chu, Winnie C.W., Chan, Henry L.Y., George, Jacob, and Wong, Vincent W.S.
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Background & Aims Noninvasive scoring systems for fibrosis are increasingly used in the clinic and in research because of their ease of use, accessibility, and low cost. However, test performance characteristics were established in groups of patients with a high prevalence of advanced fibrosis; little is known about diagnostic accuracy in low-risk populations. Methods In a cross-sectional study, 922 members of a general ambulatory population in Hong Kong (randomly selected; 18–70 years old) underwent clinical assessment from May 2008 through December 2010. All participants completed a standard questionnaire that collected information on age, sex, and history of smoking and alcohol use. Results of fasting blood tests and transient elastography were used as the reference standard to identify patients with advanced fibrosis. We assessed performance characteristics of 3 noninvasive fibrosis scoring systems: the nonalcoholic fatty liver disease fibrosis scoring system, the Fibrosis-4 scoring system, and aspartate transaminase to platelet ratio index, using standard thresholds. To calculate diagnostic test characteristics, we constructed a 2-by-2 table with the presence or absence of advanced fibrosis according to the transient elastography reading against the presence or absence of advanced fibrosis according to the scoring systems. Area under the receiver operating curve was calculated to assess overall diagnostic accuracy. Results Of the 922 individuals evaluated by transient elastography, 749 had a valid reading and 15 had advanced fibrosis (2%). The specificity of noninvasive scores in detection of advanced fibrosis approximated 100% (95% confidence interval [CI], 99%–100%), with a negative predictive value of 98% (95% CI, 97%–99%) for all systems. However, the scoring systems detected fibrosis with a low level of sensitivity, ranging from 7% (95% CI, 0%–32%) to 13% (95% CI, 2%–40%). Positive predictive values ranged from 50% (95% CI, 7%–93%) to 67% (95% CI, 9%–99%). Their negative likelihood ratios ranged from 0.87 (95% CI, 0.71%–1.06%) to 0.93 (95% CI, 0.82%–1.07%); positive likelihood ratios were uninformative because of the small number of people with positive scores. Conclusions In low-risk populations, negative results from noninvasive scoring systems reliably exclude advanced fibrosis, without requirements for further tests. Positive test results are often a false-positive result and should prompt further testing. [ABSTRACT FROM AUTHOR]
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- 2017
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43. The differential effect of socio-economic status on body mass index among Aboriginal children & adolescents.
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Kim, Siah, Macaskill, Petra, Baur, Louise, Hodson, Elisabeth M., Daylight, Jennifer, Williams, Rita, Kearns, Rachael, Vukasin, Nicola, Lyle, David M., and Craig, Jonathan C.
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CHILDREN'S health ,INDIGENOUS peoples ,CHILDHOOD obesity ,ADOLESCENT health ,SOCIOECONOMIC factors ,BODY mass index - Published
- 2014
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44. HOW ACCURATE ARE CEREBROSPINAL FLUID BIOMARKERS FOR THE DIAGNOSIS OF ALZHEIMER DISEASE? A SYSTEMATIC REVIEW.
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Zhang, Xin, Macaskill, Petra, Irwig, Les M., Olsson, Bob, Zetterberg, Henrik, Blennow, Kaj, and Loy, Clement
- Published
- 2016
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45. Accuracy of the “traffic light” clinical decision rule for serious bacterial infections in young children with fever: a retrospective cohort study
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De, Sukanya, Williams, Gabrielle J, Hayen, Andrew, Macaskill, Petra, McCaskill, Mary, Isaacs, David, and Craig, Jonathan C
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ObjectivesTo determine the accuracy of a clinical decision rule (the traffic light system developed by the National Institute for Health and Clinical Excellence (NICE)) for detecting three common serious bacterial infections (urinary tract infection, pneumonia, and bacteraemia) in young febrile children.DesignRetrospective analysis of data from a two year prospective cohort studySettingA paediatric emergency department.Participants15 781 cases of children under 5 years of age presenting with a febrile illness.Main outcome measuresClinical features were used to categorise each febrile episodes as low, intermediate, or high probability of serious bacterial infection (green, amber, and red zones of the traffic light system); these results were checked (using standard radiological and microbiological tests) for each of the infections of interest and for any serious bacterial infection.ResultsAfter combination of the intermediate and high risk categories, the NICE traffic light system had a test sensitivity of 85.8% (95% confidence interval 83.6% to 87.7%) and specificity of 28.5% (27.8% to 29.3%) for the detection of any serious bacterial infection. Of the 1140 cases of serious bacterial infection, 157 (13.8%) were test negative (in the green zone), and, of these, 108 (68.8%) were urinary tract infections. Adding urine analysis (leucocyte esterase or nitrite positive), reported in 3653 (23.1%) episodes, to the traffic light system improved the test performance: sensitivity 92.1% (89.3% to 94.1%), specificity 22.3% (20.9% to 23.8%), and relative positive likelihood ratio 1.10 (1.06 to 1.14).ConclusionThe NICE traffic light system failed to identify a substantial proportion of serious bacterial infections, particularly urinary tract infections. The addition of urine analysis significantly improved test sensitivity, making the traffic light system a more useful triage tool for the detection of serious bacterial infections in young febrile children.
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- 2017
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46. Su1043 Nonalcoholic Fatty Liver Disease and Cardiovascular Mortality in Older Individuals: A Prospective Cohort Study.
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Mahady, Suzanne E., Wong, Germaine, Turner, Robin M., Mitchell, Paul, Macaskill, Petra, Craig, Jonathan, and George, Jacob
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- 2015
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47. Liquid-based versus conventional cervical cytology – Authors' reply
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Davey, Elizabeth, Barratt, Alexandra, Irwig, Les, Macaskill, Petra, and Saville, A Marion
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- 2006
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48. Red flags to screen for malignancy and fracture in patients with low back pain: systematic review
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Downie, Aron, Williams, Christopher M, Henschke, Nicholas, Hancock, Mark J, Ostelo, Raymond W J G, de Vet, Henrica C W, Macaskill, Petra, Irwig, Les, van Tulder, Maurits W, Koes, Bart W, and Maher, Christopher G
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ObjectiveTo review the evidence on diagnostic accuracy of red flag signs and symptoms to screen for fracture or malignancy in patients presenting with low back pain to primary, secondary, or tertiary care.DesignSystematic review.Data sourcesMedline, OldMedline, Embase, and CINAHL from earliest available up to 1 October 2013.Inclusion criteriaPrimary diagnostic studies comparing red flags for fracture or malignancy to an acceptable reference standard, published in any language.Review methodsAssessment of study quality and extraction of data was conducted by three independent assessors. Diagnostic accuracy statistics and post-test probabilities were generated for each red flag.ResultsWe included 14 studies (eight from primary care, two from secondary care, four from tertiary care) evaluating 53 red flags; only five studies evaluated combinations of red flags. Pooling of data was not possible because of index test heterogeneity. Many red flags in current guidelines provide virtually no change in probability of fracture or malignancy or have untested diagnostic accuracy. The red flags with the highest post-test probability for detection of fracture were older age (9%, 95% confidence interval 3% to 25%), prolonged use of corticosteroid drugs (33%, 10% to 67%), severe trauma (11%, 8% to 16%), and presence of a contusion or abrasion (62%, 49% to 74%). Probability of spinal fracture was higher when multiple red flags were present (90%, 34% to 99%). The red flag with the highest post-test probability for detection of spinal malignancy was history of malignancy (33%, 22% to 46%).ConclusionsWhile several red flags are endorsed in guidelines to screen for fracture or malignancy, only a small subset of these have evidence that they are indeed informative. These findings suggest a need for revision of many current guidelines.
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- 2013
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49. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses of randomised controlled trials
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Sterne, Jonathan A C, Sutton, Alex J, Ioannidis, John P A, Terrin, Norma, Jones, David R, Lau, Joseph, Carpenter, James, Rücker, Gerta, Harbord, Roger M, Schmid, Christopher H, Tetzlaff, Jennifer, Deeks, Jonathan J, Peters, Jaime, Macaskill, Petra, Schwarzer, Guido, Duval, Sue, Altman, Douglas G, Moher, David, and Higgins, Julian P T
- Published
- 2011
50. The accuracy of clinical symptoms and signs for the diagnosis of serious bacterial infection in young febrile children: prospective cohort study of 15 781 febrile illnesses
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Craig, Jonathan C, Williams, Gabrielle J, Jones, Mike, Codarini, Miriam, Macaskill, Petra, Hayen, Andrew, Irwig, Les, Fitzgerald, Dominic A, Isaacs, David, and McCaskill, Mary
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OBJECTIVE:s To evaluate current processes by which young children presenting with a febrile illness but suspected of having serious bacterial infection are diagnosed and treated, and to develop and test a multivariable model to distinguish serious bacterial infections from self limiting non-bacterial illnesses. Design Two year prospective cohort study. Setting The emergency department of The Children’s Hospital at Westmead, Westmead, Australia. Participants Children aged less than 5 years presenting with a febrile illness between 1 July 2004 and 30 June 2006. Intervention A standardised clinical evaluation that included mandatory entry of 40 clinical features into the hospital’s electronic record keeping system was performed by physicians. Serious bacterial infections were confirmed or excluded using standard radiological and microbiological tests and follow-up. MAIN OUTCOME MEASURES: Diagnosis of one of three key types of serious bacterial infection (urinary tract infection, pneumonia, and bacteraemia), and the accuracy of both our clinical decision making model and clinician judgment in making these diagnoses. RESULTS: We had follow-up data for 93% of the 15 781 instances of febrile illnesses recorded during the study period. The combined prevalence of any of the three infections of interest (urinary tract infection, pneumonia, or bacteraemia) was 7.2% (1120/15 781, 95% confidence interval (CI) 6.7% to 7.5%), with urinary tract infection the diagnosis in 543 (3.4%) cases of febrile illness (95% CI 3.2% to 3.7%), pneumonia in 533 (3.4%) cases (95% CI 3.1% to 3.7%), and bacteraemia in 64 (0.4%) cases (95% CI 0.3% to 0.5%). Almost all (>94%) of the children with serious bacterial infections had the appropriate test (urine culture, chest radiograph, or blood culture). Antibiotics were prescribed acutely in 66% (359/543) of children with urinary tract infection, 69% (366/533) with pneumonia, and 81% (52/64) with bacteraemia. However, 20% (2686/13 557) of children without bacterial infection were also prescribed antibiotics. On the basis of the data from the clinical evaluations and the confirmed diagnosis, a diagnostic model was developed using multinomial logistic regression methods. Physicians’ diagnoses of bacterial infection had low sensitivity (10-50%) and high specificity (90-100%), whereas the clinical diagnostic model provided a broad range of values for sensitivity and specificity. CONCLUSIONS: Emergency department physicians tend to underestimate the likelihood of serious bacterial infection in young children with fever, leading to undertreatment with antibiotics. A clinical diagnostic model could improve decision making by increasing sensitivity for detecting serious bacterial infection, thereby improving early treatment.
- Published
- 2010
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