Can supervise: YES
Cheah, SL, Scarf, VL, Rossiter, C, Thornton, C & Homer, CSE 2019, 'Creating the first national linked dataset on perinatal and maternal outcomes in Australia: Methods and challenges.', Journal of biomedical informatics, vol. 93.View/Download from: Publisher's site
BACKGROUND:Data linkage offers a powerful mechanism for examining healthcare outcomes across populations and can generate substantial robust datasets using routinely collected electronic data. However, it presents methodological challenges, especially in Australia where eight separate states and territories maintain health datasets. This study used linked data to investigate perinatal and maternal outcomes in relation to place of birth. It examined data from all eight jurisdictions regarding births planned in hospitals, birth centres and at home. Data linkage enabled the first Australia-wide dataset on birth outcomes. However, jurisdictional differences in data collection created challenges in obtaining comparable cohorts of women with similar low-risk pregnancies in all birth settings. The objective of this paper is to describe the techniques for managing previously linked data, and specifically for ensuring the resulting dataset contained only low-risk pregnancies. METHODS:This paper indicates the procedures for preparing and merging linked perinatal, inpatient and mortality data from different sources, providing technical guidance to address challenges arising in linked data study designs. RESULTS:We combined data from eight jurisdictions linking four collections of administrative healthcare and civil registration data. The merging process ensured that variables were consistent, compatible and relevant to study aims. To generate comparable cohorts for all three birth settings, we developed increasingly complex strategies to ensure that the dataset eliminated women with pregnancies at risk of complications during labour and birth. It was then possible to compare birth outcomes for comparable samples, enabling specific examination of the impact of birth setting on maternal and infant safety across Australia. CONCLUSIONS:Data linkage is a valuable resource to enhance knowledge about birth outcomes from different settings, notwithstanding methodological challenges...
Homer, CSE, Cheah, SL, Rossiter, C, Dahlen, HG, Ellwood, D, Foureur, MJ, Forster, DA, McLachlan, HL, Oats, JJN, Sibbritt, D, Thornton, C & Scarf, VL 2019, 'Maternal and perinatal outcomes by planned place of birth in Australia 2000 - 2012: a linked population data study.', BMJ open, vol. 9, no. 10.View/Download from: Publisher's site
OBJECTIVE:To compare perinatal and maternal outcomes for Australian women with uncomplicated pregnancies according to planned place of birth, that is, in hospital labour wards, birth centres or at home. DESIGN:A population-based retrospective design, linking and analysing routinely collected electronic data. Analysis comprised χ2 tests and binary logistic regression for categorical data, yielding adjusted ORs. Continuous data were analysed using analysis of variance. SETTING:All eight Australian states and territories. PARTICIPANTS:Women with uncomplicated pregnancies who gave birth between 2000 and 2012 to a singleton baby in cephalic presentation at between 37 and 41 completed weeks' gestation. Of the 1 251 420 births, 1 171 703 (93.6%) were planned in hospital labour wards, 71 505 (5.7%) in birth centres and 8212 (0.7%) at home. MAIN OUTCOME MEASURES:Mode of birth, normal labour and birth, interventions and procedures during labour and birth, maternal complications, admission to special care/high dependency or intensive care units (mother or infant) and perinatal mortality (intrapartum stillbirth and neonatal death). RESULTS:Compared with planned hospital births, the odds of normal labour and birth were over twice as high in planned birth centre births (adjusted OR (AOR) 2.72; 99% CI 2.63 to 2.81) and nearly six times as high in planned home births (AOR 5.91; 99% CI 5.15 to 6.78). There were no statistically significant differences in the proportion of intrapartum stillbirths, early or late neonatal deaths between the three planned places of birth. CONCLUSIONS:This is the first Australia-wide study to examine outcomes by planned place of birth. For healthy women in Australia having an uncomplicated pregnancy, planned births in birth centres or at home are associated with positive maternal outcomes although the number of homebirths was small overall. There were no significant differences in the perinatal mortality rate, although the absolute numbers of deaths w...
Scarf, VL, Viney, R, Yu, S, Foureur, M, Rossiter, C, Dahlen, H, Thornton, C, Cheah, SL & Homer, CSE 2019, 'Mapping the trajectories for women and their babies from births planned at home, in a birth centre or in a hospital in New South Wales, Australia, between 2000 and 2012', BMC Pregnancy and Childbirth, vol. 19, no. 1.View/Download from: Publisher's site
Hosie, A, Phillips, J, Lam, L, Kochovska, S, Noble, B, Brassil, M, Kurrle, SE, Cumming, A, Caplan, GA, Chye, R, Le, B, Ely, EW, Lawlor, PG, Bush, SH, Davis, JM, Lovell, M, Brown, L, Fazekas, B, Cheah, SL, Edwards, L & Agar, M 2019, 'Multicomponent non-pharmacological intervention to prevent delirium for hospitalised people with advanced cancer: study protocol for a phase II cluster randomised controlled trial.', BMJ open, vol. 9, no. 1, pp. e026177-e026177.View/Download from: Publisher's site
INTRODUCTION:Delirium is a significant medical complication for hospitalised patients. Up to one-third of delirium episodes are preventable in older inpatients through non-pharmacological strategies that support essential human needs, such as physical and cognitive activity, sleep, hydration, vision and hearing. We hypothesised that a multicomponent intervention similarly may decrease delirium incidence, and/or its duration and severity, in inpatients with advanced cancer. Prior to a phase III trial, we aimed to determine if a multicomponent non-pharmacological delirium prevention intervention is feasible and acceptable for this specific inpatient group. METHODS AND ANALYSIS:The study is a phase II cluster randomised wait-listed controlled trial involving inpatients with advanced cancer at four Australian palliative care inpatient units. Intervention sites will introduce delirium screening, diagnostic assessment and a multicomponent delirium prevention intervention with six domains of care: preserving natural sleep; maintaining optimal vision and hearing; optimising hydration; promoting communication, orientation and cognition; optimising mobility; and promoting family partnership. Interdisciplinary teams will tailor intervention delivery to each site and to patient need. Control sites will first introduce only delirium screening and diagnosis, later implementing the intervention, modified according to initial results. The primary outcome is adherence to the intervention during the first seven days of admission, measured for 40 consecutively admitted eligible patients. Secondary outcomes relate to fidelity and feasibility, acceptability and sustainability of the study intervention, processes and measures in this patient population, using quantitative and qualitative measures. Delirium incidence and severity will be measured to inform power calculations for a future phase III trial. ETHICS AND DISSEMINATION:Ethical approval was obtained for all four sites. Trial r...
Hosie, A, Siddiqi, N, Featherstone, I, Johnson, M, Lawlor, PG, Bush, SH, Amgarth-Duff, I, Edwards, L, Cheah, SL, Phillips, J & Agar, M 2019, 'Inclusion, characteristics and outcomes of people requiring palliative care in studies of non-pharmacological interventions for delirium: A systematic review.', Palliative medicine, vol. 33, no. 8, pp. 878-899.View/Download from: Publisher's site
BACKGROUND:Delirium is common, distressing, serious and under-researched in specialist palliative care settings. OBJECTIVES:To examine whether people requiring palliative care were included in non-pharmacological delirium intervention studies in inpatient settings, how they were characterised and what their outcomes were. DESIGN:Systematic review (PROSPERO 2017 CRD42017062178). DATA SOURCES:Systematic search in March 2017 for non-pharmacological delirium intervention studies in adult inpatients. Database search terms were 'delirium', 'hospitalisation', 'inpatient', 'palliative care', 'hospice', 'critical care' and 'geriatrics'. Scottish Intercollegiate Guidelines Network methodological checklists guided risk of bias assessment. RESULTS:The 29 included studies were conducted between 1994 and 2015 in diverse settings in 15 countries (9136 participants, mean age = 76.5 years (SD = 8.1), 56% women). Most studies tested multicomponent interventions (n = 26) to prevent delirium (n = 19). Three-quarters of the 29 included studies (n = 22) excluded various groups of people requiring palliative care; however, inclusion criteria, participant diagnoses, illness severity and mortality indicated their presence in almost all studies (n = 26). Of these, 21 studies did not characterise participants requiring palliative care or report their specific outcomes (72%), four reported outcomes for older people with frailty, dementia, cancer and comorbidities, and one was explicitly focused on people receiving palliative care. Study heterogeneity and limitations precluded definitive determination of intervention effectiveness and only allowed interpretations of feasibility for people requiring palliative care. Acceptability outcomes (intervention adverse events and patients' subjective experience) were rarely reported overall. CONCLUSION:Non-pharmacological delirium interventions have frequently excluded and under-characterised people requiring palliative care and infrequently reported ...
Cheah, S 2015, 'An examination of subject variables that influence pressure pain threshold'.
Background: Pain is a primary clinical concern for most people. Pain is the most common reason for seeking any form of health assistance be it medical, dental, physiotherapeutic or alternative disciplines. Pain threshold is defined as the lowest application of a stimulus that is perceived as pain. Experimental pain studies use a range of pain challenges including electrical, heat or cold, ischaemic and pressure. Some carry a higher potential risk of tissue injury or the sensations experienced are less acceptable to subjects. Pressure pain threshold (PPT), measured by a simple mechanical algometer is an attractive alternative well-suited for non-invasive repeated measurements on multiple sites not limited to limbs over short time intervals in a relaxed setting. Since 2000, the University of Technology Sydney had conducted eight PPT studies and collected over 47,500 baseline PPT measurements on 262 healthy subjects at 24 regional sites with three or four PPT readings for each site at each session of four to eight occasions of at least one week apart. Research Study One included seven studies with over 32,000 pre-intervention PPT measures on 235 healthy subjects at 17 sites with three PPT measures at each occasion for four consecutive occasions. These data were being analysed to develop comprehensive epidemiological profiles that assess relationships between PPT with subject variables (gender, age, BMI) and duration of temporal sessions. Research Study Two assessed the PPT at two affected and two non-affected sites of 20 patients with lateral epicondylitis. Research Study Three examined the inter-device reliability between mechanical and electronic algometers at six sites of 17 subjects. Aims: Research Study One explored the temporal stability of possible relationships between subject variables of gender, age and BMI, the duration of temporal sessions with the regional PPT at each measurement site. Research Study Two assessed the regional PPT measures at LI10 and LI...
Chenoweth, L, Jeon, Y-H, Stein-Parbury, J, Forbes, I, Fleming, R, Cook, J, Cheah, S, Fletcher, S & Tinslay, L 2015, 'PerCEN trial participant perspectives on the implementation and outcomes of person-centered dementia care and environments', INTERNATIONAL PSYCHOGERIATRICS, vol. 27, no. 12, pp. 2045-2057.View/Download from: Publisher's site
Cheah, S 2006, 'Composite Cubic Bezier Surface with C^r Continuity', Sunway Academic Journal, vol. 3, pp. 21-33.
The Bézier surface with Cr continuity on each common boundary between two composite triangular Bézier patches is generated. The directional derivatives on the Bernstein polynomials are discussed. This is to ensure that the Cr continuity is maintained along the boundary between the piecewise polynomials. The composite patches are then generated by elevating the degree of the Bézier triangles.
Cheah, S 1988, 'Malay version: Algoritma subbahagian untuk penjanaan lengkung dan permukaan spline di dalam CAGDEnglish version: Subdivision algorithms for generating spline curves and surfaces in Computer Aided Geometric Design'.