Differing Definitions of First-Ever Stroke Influence Incidence Estimates More than Trends: A Study Using Linked Administrative Data.

INTRODUCTION: Researchers apply varying definitions when measuring stroke incidence using administrative data. We aimed to investigate the sensitivity of incidence estimates to varying definitions of stroke and lookback periods and to provide updated incidence rates and trends for Western Australia (WA). METHODS: We used linked state-wide hospital and death data from 1985 to 2017 to identify incident strokes from 2005 to 2017. A standard definition was applied which included strokes coded as the principal hospital diagnosis or the underlying cause of death, with a 10-year lookback used to clear prevalent cases. Alternative definitions were compared against the standard definition by percentage difference in case numbers. Age-standardised incidence rates were calculated, and age- and sex-adjusted Poisson regression models were used to estimate incidence trends. RESULTS: The standard definition with a 10-year lookback period captured 31,274 incident strokes. Capture increased by 19.3% when including secondary diagnoses, 4.1% when including nontraumatic subdural and extradural haemorrhage, and 8.1% when including associated causes of death. Excluding death records reduced capture by 11.1%. A 20-year lookback reduced over-ascertainment by 2.0%, and a 1-year lookback increased capture by 13.3%. Incidence declined 0.6% annually (95% confidence interval -0.9, -0.3). Annual reductions were similar for most definitions except when death records were excluded (-0.1%, CI: -0.4, 0.2) and with the shortest lookback periods (greatest annual reduction). CONCLUSION: Stroke incidence has declined in WA. Differing methods of identifying stroke influence estimates of incidence to a greater extent than estimates of trends. Reductions in stroke incidence over time are primarily driven by declines in fatal strokes.

Regularity and Continuity of GP Contacts and Use of Statins Amongst People at Risk of Cardiovascular Events.

BACKGROUND: Regularity and continuity of general practitioner (GP) contacts are associated with reduced hospitalisation. Opportunities for improved medication management are cited as a potential cause. OBJECTIVE: Determine associations between continuity and regularity of primary care and statin use amongst individuals at risk of cardiovascular disease (CVD) outcomes. DESIGN: Observational cohort study using self-report and administrative data from 267,153 participants of the Sax Institute's 45 and Up Study conducted in New South Wales, Australia. from 2006 to 2009. Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) data, from Services Australia, were linked to survey, hospital and death data by the NSW Centre for Health Record Linkage. PARTICIPANTS: The 45 and Up Study participants at risk of CVD outcomes based on self-report and administrative data, divided into existing users and potential users based on dispensing records through the exposure period. MAIN MEASURES: The Continuity of Care index (COC), measuring whether patients see the same GP, and an index assessing whether GP visits are on a regular basis, measured from July 2011 to June 2012. Amongst potential users, statin initiation from July 2012 to June 2013 was assessed using logistic regression; amongst existing users, adherence was assessed from July 2012 to June 2015 using Cox regression (non-adherence being 30 days without statins). KEY RESULTS: Amongst 29,420 potential users, the most regular quintile had 1.22 times the odds of initiating statin (95%CI 1.11-1.34), while the high continuity group had an odds ratio of 1.12 (95%CI 1.02-1.24). Amongst 30,408 existing users, the most regular quintile had 0.82 the hazard of non-adherence (95%CI 0.78-0.87); the high continuity group had a hazard ratio of 0.89 (95%CI 0.84-0.94). CONCLUSIONS: Regularity and continuity of care impact on medication management. It is possible that this mediates impacts on hospitalisation. Where there is a risk of unobserved confounding, potential causal pathways should be investigated.

Effect Modification of Multimorbidity on the Association Between Regularity of General Practitioner Contacts and Potentially Avoidable Hospitalisations.

BACKGROUND: Scheduled regular contact with the general practitioner (GP) may lower the risk of potentially avoidable hospitalisations (PAHs). Despite the high prevalence of multimorbidity, little is known about its effect on the relationship between regularity of GP contact and PAHs. OBJECTIVE: To investigate potential effect modification of multimorbidity on the relationship between regularity of GP contact and probability of PAHs. DESIGN: A retrospective, cross-sectional study. PARTICIPANTS: 229,964 individuals aged 45 years and older from the 45 and Up Study in New South Wales, Australia, from 2009 to 2015. MAIN MEASURES: The main exposure was regularity of GP contact (capturing dispersion of GP contacts); the outcomes were PAHs evaluated by unplanned hospitalisations, chronic ambulatory care sensitive condition (ACSC) hospitalisations and unplanned chronic ACSC hospitalisations. Multivariable logistic regression models and population attributable fractions (PAF) were conducted to identify effect modification of multimorbidity, assessed by Rx-Risk comorbidity score. KEY RESULTS: Compared with the lowest quintile of regularity, the highest quintile had significantly lower predicted probability of unplanned admission (- 79.9 per 1000 people at risk, 95% confidence interval (CI) - 85.6; - 74.2), chronic ACSC (- 6.07 per 1000 people at risk, 95%CI - 8.07; - 4.08) and unplanned chronic ACSC hospitalisation (- 4.68 per 1000 people at risk, 95%CI - 6.11; - 3.26). Effect modification of multimorbidity was observed. Specifically, the PAF among people with no multimorbidity indicated that 31.7% (95%CI 28.7-34.4%) of unplanned, 36.4% (95%CI 25.1-45.9%) of chronic ACSC and 48.9% (95%CI 32.9-61.1%) of unplanned chronic ACSC hospitalisation would be reduced by a shift to the highest quintile of regularity. However, among people with 10+ morbidities, the proportional reduction was only 5.2% (95%CI 3.8-6.5%), 9.0% (95%CI 0.5-16.8%) and 17.8% (95%CI 5.4-28.5%), respectively. CONCLUSIONS: Weakening of the association between regularity and PAHs with increasing levels of multimorbidity suggests a need to improve primary care support to prevent PAHs for patients with multimorbidity.

The association between general practitioner regularity of care and 'high use' hospitalisation.

BACKGROUND: In Australia, as in many high income countries, there has been a movement to improve out-of-hospital care. If primary care improvements can yield appropriately lower hospital use, this would improve productive efficiency. This is especially important among 'high cost users', a small group of patients accounting for disproportionately high hospitalisation costs. This study aimed to assess the association between regularity of general practitioner (GP) care and 'high use' hospitalisation. METHODS: This retrospective, cohort study used linked administrative and survey data from the 45 and Up Study, conducted in New South Wales, Australia. The exposure was regularity of GP care between 1 July 2005 and 30 June 2009, categorised by quintile (lowest to highest). Outcomes were 'high use' of hospitalisation (defined as ≥3 and ≥ 5 admissions within 12 months), extended length of stay (LOS, ≥30 days), a combined metric (≥3 hospitalisations in a 12 month period where ≥1 hospitalisation was ≥30 days) and 30-day readmission between 1 July 2009 and 31 December 2017. Associations were assessed using multivariable logistic regression. Potential for outcome prevention in a hypothetical scenario where all individuals attain the highest GP regularity was estimated via the population attributable fraction (PAF). RESULTS: Of 253,500 eligible participants, 15% had ≥3 and 7% had ≥5 hospitalisations in a 12-month period. Five percent of the cohort had a hospitalisation lasting ≥30 days and 25% had a readmission within 30 days. Compared with lowest regularity, highest regularity was associated with between 6% (p < 0.001) and 11% (p = 0.027) lower odds of 'high use'. There was a 7-8% reduction in odds for all regularity levels above 'low' regularity for LOS ≥30 days. Otherwise, there was no clear sequential reduction in 'high use' with increasing regularity. The PAF associated with a move to highest regularity ranged from 0.05 to 0.13. The number of individuals who could have had an outcome prevented was estimated to be between 269 and 2784, depending on outcome. CONCLUSIONS: High GP regularity is associated with a decreased likelihood of 'high use' hospitalisation, though for most outcomes there was not an apparent linear association with regularity.

Assessing the cost-effectiveness of RT Prepare: A radiation therapist-delivered intervention for reducing psychological distress prior to radiotherapy.

OBJECTIVE: To determine the cost-effectiveness of RT Prepare in reducing breast cancer patients' psychological distress before treatment, compared with usual care. METHODS: RT Prepare, an intervention involving patient education and support consultations with a radiation therapist (RT), was implemented at three Australian sites (Australian New Zealand Clinical Trials Registration: ACTRN12611001000998). The primary outcome was change in psychological distress using the Hospital Anxiety and Depression Scale (HADS); secondary outcomes were changes in quality of life (QoL) and additional health service use. Costs (2015 $AU) included consultation time and training delivery. Between-group comparisons of HADS and QoL used generalised linear mixed models, and comparisons of health service use used negative binomial regression. Incremental cost-effectiveness ratios (ICERs) indicated mean costs per 1-point decrease in HADS score. Sensitivity analyses explored variation in facility size and uncertainty in intervention effectiveness. RESULTS: Among 218 controls and 189 intervention participants, the intervention significantly lowered HADS scores at treatment commencement (adjusted mean difference 1.06 points). There was no significant effect on QoL or additional service use. Mean intervention costs were AU$171 per participant (US$130, €119) mostly related to RT training (approximately AU$142 (US$108, €99). An ICER of $158 (US$120, €110) was estimated. Cost-effectiveness improved in a sensitivity analysis representing a large facility with higher patient numbers. CONCLUSION: This study provides new data on the cost-effectiveness of an RT-delivered intervention to reduce psychological distress prior to treatment, which will be useful to inform delivery of similar services. As most costs were upfront, cost-effectiveness would likely improve if implemented as standard care.

Regularity of contact with GPs: Measurement approaches to improve valid associations with hospitalization.

BACKGROUND: Studies examine longitudinal continuity of GP contact though few consider 'regularity of GP contact', i.e., the dispersion of contacts over time. Increased regularity may indicate planned ongoing care. Current measures of regularity may be correlated with the number of contacts and may not isolate the phenomenon of interest. OBJECTIVES: To compare two published and one newly developed regularity index in terms of their ability to measure regularity of GP contacts independently of the number of contacts and the impact on their association with hospitalization. METHODS: A cohort at risk of diabetes-related hospitalization in Western Australia from 1990 to 2004 was identified using linked administrative data. For each regularity index, relationships with number of GP contacts were assessed. Hospitalization was then regressed on each index with and without number of contacts as a covariate. RESULTS: Among 153,414 patients the new regularity index showed a reduced association with number of contacts compared with existing indices. Associations with hospitalization differed between measures; for previously published indices, there were no significant associations between regularity and hospitalization, whereas on the new index, most regular GP contact was associated with reduced hospitalization (IRR = 0.90, 95% CI = 0.88-0.93). When number of contacts was added as a covariate, point estimates for this index showed little change, whereas for existing measures this addition changed point estimates. CONCLUSION: A new measure of regularity of GP contact was less correlated with the number of contacts than previously published measures and better suited to estimating unconfounded relationships of regularity with hospitalization.

The cost-effectiveness of a telephone-based intervention to support caregivers of older people discharged from hospital.

BACKGROUND: A telephone intervention for caregivers of older people discharged from hospital was shown to improve preparedness to care, reduce caregiver strain and caregiver distress. No cost-effectiveness analysis has been published on this, or similar interventions. The study aims addressed here were to examine whether positive outcomes for caregivers resulting from the Further Enabling Care at Home (FECH) program changed the use and costs of health services by patients; and to assess cost-effectiveness. METHODS: A single-blind randomised controlled trial compared FECH to usual care. FECH involved a specially trained nurse addressing support needs of caregivers of older patients discharged from hospital. A minimum clinically important difference in preparedness to care was defined as an increase in Preparedness for Caregiving scale score of ≥ two points from baseline. Designated data collection was at: Time 1, within four days of discharge; Time 2, 15-21 days post-discharge; and Time 3, six weeks post-discharge. A last observation carried forward approach to loss to follow-up was used, with a sensitivity analysis including only those who completed all time points. Patient use of hospital, emergency department (ED) and ambulance services were captured for 12 weeks post-discharge using administrative data. Costs included nurse time supporting caregivers, resources used by the nurse, and time taken training the nurse to deliver FECH. Cost-effectiveness was assessed using decision trees for preparedness for caregiving. RESULTS: Sixty-two intervention dyads and 79 controls provided complete data. A significantly greater proportion of intervention group caregivers reported improved preparedness to care to Time 2 (36.4% v 20.9%, p = 0.029), though this was not sustained to Time 3. The intervention cost $AUD268.28 above usual care per caregiver. No significant differences were observed in health service use between groups. The incremental cost-effectiveness ratio for each additional caregiver reporting improved preparedness to care at Time 2 was $AUD1,730.84. CONCLUSIONS: To our knowledge this is the first work to calculate the cost-effectiveness of a telephone-delivered intervention designed to support caregivers of older people post-discharge, and will support decision-making regarding implementation. Further research should examine different settings, and assess impacts on health service use with larger samples and a longer follow-up. TRIAL REGISTRATION: Australian and New Zealand Clinical Trial Registry: ACTRN12614001174673 . Registered 07/11/2014.

RT Prepare: a radiation therapist-delivered intervention reduces psychological distress in women with breast cancer referred for radiotherapy.

BACKGROUND: The aims of this study were to determine whether a radiation therapist-led patient education intervention (RT Prepare) reduced breasts cancer patients' psychological distress (primary endpoint); anxiety, depression and concerns about radiotherapy, and increased knowledge of radiotherapy and preparedness (secondary endpoints). Patient health system usage and costs were also assessed. METHODS: A multiple-baseline study across three sites. The RT Prepare intervention comprised two consultations with a radiation therapist: prior to treatment planning and on the first day of treatment. Radiation therapists focused on providing sensory and procedural information and addressing patients' pre-treatment anxiety. Usual care data were collected prior to intervention commencement. Data collection occurred: after meeting their radiation oncologist, prior to treatment planning, first day of treatment and after treatment completion. Multilevel mixed effects regression models were used. RESULTS: In total, 218 usual care and 190 intervention patients participated. Compared with usual care, intervention participants reported lower psychological distress at treatment commencement (p = 0.01); lower concerns about radiotherapy (p < 0.01); higher patient knowledge (p < 0.001); higher preparedness for procedural concerns (p < 0.001) and higher preparedness for sensory-psychological concerns at treatment planning (p < 0.001). Mean within-trial costs per patient were estimated at $AU159 (US$120); mean ongoing costs at $AU35 (US$26). CONCLUSION: The RT Prepare intervention was effective in reducing breast cancer patients' psychological distress and preparing patients for treatment. This intervention provides an opportunity for radiation therapists to extend their role into providing patients with information and support prior to treatment to reduce psychological distress.

Assessing the feasibility of anticholinergic burden scales and measures in administrative data: A systematic review.

AIM: This systematic review aimed to identify and evaluate the quality and adaptability of existing anticholinergic burden scales and measures by using administrative dispensing data. METHOD: A comprehensive literature search was conducted using the Medline, Embase, CINAHL, and Google Scholar databases from 2001 to 2022. Studies that introduced, updated, or modified anticholinergic burden scales and measures were included in this review. Quality assessment considered various aspects, including scoring systems, tool development criteria, and specific requirements tailored for administrative data. RESULTS: Twenty-eight anticholinergic burden scales and measures were identified in 14 countries. The Modified Anticholinergic Risk Scale excelled in the scoring system, while the German Anticholinergic Burden Scale stood out in the scale development process. However, significant variability was observed in methodologies, medication listings, and adaptability to administrative data. Quality assessment considers aspects such as potency, dose, exposure duration, longitudinal measurement, clinical interpretation, and compatibility with administrative data variables. The evaluation also considered tool development criteria including evidence for medication selection, panel expertise, relevance, updating methods, international applicability, validation, and clinical guidance. CONCLUSION: This review emphasizes the importance of adaptable and robust tools that can work well with administrative data to ensure patient safety and better health outcomes, given the ongoing evolution of anticholinergic medications. The findings of this systematic review provide valuable insights for clinicians and researchers in selecting the most appropriate anticholinergic burden scale or measure according to their specific needs and data sources. This systematic review was registered with PROSPERO (registration ID CRD42023423959).

Temporal trends in concordance between ICD-coded and cardiac biomarker-classified hospitalisation rates for acute coronary syndromes: a linked hospital and biomarker data study.

BACKGROUND: Since 2000, the definition of myocardial infarction (MI) has evolved with reliance on cardiac troponin (cTn) tests. The implications of this change on trends of acute coronary syndrome (ACS) subtypes obtained from routinely collected hospital morbidity data are unclear. Using person-linked hospitalisation data, we compared International Classification of Diseases (ICD)-coded data with biomarker-classified admission rates for ST-segment elevation MI (STEMI), non-STEMI (NSTEMI) and unstable angina (UA) in Western Australia (WA). METHODS: We used linked hospitalisation data from all WA tertiary hospitals to identify patients with a principal diagnosis of STEMI, NSTEMI or UA between 2002 and 2016. Linked biomarker results were classified as 'diagnostic' for MI according to established criteria. We calculated age-standardised and sex-standardised rates (ASSRs) for ICD-coded versus biomarker-classified admissions by ACS subtypes and estimated annual change in admissions using Poisson regression adjusting for age and sex. RESULTS: There were 37 272 ACS admissions in 30 683 patients (64.2% male), and 96% of cases had linked biomarker data, predominantly conventional cTn at the start and high-sensitive cTn from late 2013. Despite lower ASSRs, trends in MI classified with a diagnostic biomarker were concordant with ICD-coded admissions rates for both STEMI and NSTEMI. Between 2002 and 2010, STEMI rates declined by 4.1% (95% CI 5.0%, 3.1%) and 3.4% (95% CI 4.6%, 2.3%) in ICD-coded and biomarker-classified admissions, respectively, and both plateaued thereafter. For NSTEMI between 2002 and 2010, the ICD-coded and biomarker-classified rates increased 8.0% per year (95% CI 7.2%, 8.9%) and 8.0% (95% CI 7.0%, 9.0%), respectively, and both subsequently declined. For UA, both ICD-coded and biomarker-classified UA admission rates declined in a steady and concordant manner between 2002 and 2016. CONCLUSIONS: The present study supports the validity of using administrative data to monitor population trends in ACS subtypes as they appear to generally reflect the redefinition of MI in the troponin era.

Demonstrating the use of population level data to investigate trends in the rate, radiation dose and cost of Computed Tomography across clinical groups: Are there any areas of concern?

INTRODUCTION: Increases in computed tomography (CT) use may not always reflect clinical need or improve outcomes. This study aimed to demonstrate how population level data can be used to identify variations in care between patient groups, by analysing system-level changes in CT use around the diagnosis of new conditions. METHODS: Retrospective repeated cross-sectional observational study using West Australian linked administrative records, including 504,723 adults diagnosed with different conditions in 2006, 2012 and 2015. For 90 days pre/post diagnosis, CT use (any and 2+ scans), effective dose (mSv), lifetime attributable risk (LAR) of cancer incidence and mortality from CT, and costs were assessed. RESULTS: CT use increased from 209.4 per 1000 new diagnoses in 2006 to 258.0 in 2015; increases were observed for all conditions except neoplasms. Healthcare system costs increased for all conditions but neoplasms and mental disorders. Effective dose increased substantially for respiratory (+2.5 mSv, +23.1%, P < 0.001) and circulatory conditions (+2.1 mSv, +15.4%, P < 0.001). The LAR of cancer incidence and mortality from CT increased for endocrine (incidence +23.4%, mortality +18.0%) and respiratory disorders (+21.7%, +23.3%). Mortality LAR increased for circulatory (+12.1%) and nervous system (+11.0%) disorders. The LAR of cancer incidence and mortality reduced for musculoskeletal system disorders, despite an increase in repeated CT in this group. CONCLUSIONS: Use and costs increased for most conditions except neoplasms and mental and behavioural disorders. More strategic CT use may have occurred in musculoskeletal conditions, while use and radiation burden increased for respiratory, circulatory and nervous system conditions. Using this high-level approach we flag areas requiring deeper investigation into appropriateness and value of care.

Association between long-term use of calcium channel blockers (CCB) and the risk of breast cancer: a retrospective longitudinal observational study protocol.

INTRODUCTION: Calcium channel blockers (CCB), a commonly prescribed antihypertensive (AHT) medicine, may be associated with increased risk of breast cancer. The proposed study aims to examine whether long-term CCB use is associated with the development of breast cancer and to characterise the dose-response nature of any identified association, to inform future hypertension management. METHODS AND ANALYSIS: The study will use data from 2 of Australia's largest cohort studies; the Australian Longitudinal Study on Women's Health, and the 45 and Up Study, combined with the Rotterdam Study. Eligible women will be those with diagnosed hypertension, no history of breast cancer and no prior CCB use at start of follow-up (2004-2009). Cumulative dose-duration exposure to CCB and other AHT medicines will be captured at the earliest date of: the outcome (a diagnosis of invasive breast cancer); a competing risk event (eg, bilateral mastectomy without a diagnosis of breast cancer, death prior to any diagnosis of breast cancer) or end of follow-up (censoring event). Fine and Gray competing risks regression will be used to assess the association between CCB use and development of breast cancer using a generalised propensity score to adjust for baseline covariates. Time-varying covariates related to interaction with health services will also be included in the model. Data will be harmonised across cohorts to achieve identical protocols and a two-step random effects individual patient-level meta-analysis will be used. ETHICS AND DISSEMINATION: Ethical approval was obtained from the following Human research Ethics Committees: Curtin University (ref No. HRE2022-0335), NSW Population and Health Services Research Ethics Committee (2022/ETH01392/2022.31), ACT Research Ethics and Governance Office approval under National Mutual Acceptance for multijurisdictional data linkage research (2022.STE.00208). Results of the proposed study will be published in high-impact journals and presented at key scientific meetings. TRIAL REGISTRATION NUMBER: NCT05972785.

Computed Tomography Angiography for Detection of Pulmonary Embolism in Western Australia Shows Increasing Use with Decreasing Diagnostic Yield.

(1) Background: Pulmonary embolism (PE) can be fatal. Computed tomography pulmonary angiography (CTPA) can accurately diagnose PE, but it should be used only when reasonable pre-test probability exists. Overtesting with CTPA exposes patients to excess ionizing radiation and contrast media, while PE overdiagnosis leads to the treatment of small emboli unlikely to cause harm. This study assessed trends in CTPA use and diagnostic yield. We also assessed trends in PE hospitalizations and mortality to indicate PE severity. (2) Methods: Analysis of Western Australian linked administrative data for 2003-2015 including hospitalizations, emergency department (ED) attendances, and CTPA performed at hospitals. Age-sex standardized trends were calculated for CTPA use, PE hospitalizations, and mortality (as a proxy for severity). Logistic regression assessed diagnostic yield of CTPA following unplanned ED presentations. (3) Results: CTPA use increased from 3.3 per 10,000 person-years in 2003 (95% CI 3.0-3.6) to 17.1 per 10,000 person-years (16.5-17.7) in 2015. Diagnostic yield of CTPA increased from 12.7% in 2003 to 17.4% in 2005, declining to 12.2% in 2015 (p = 0.049). PE hospitalizations increased from 3.8 per 10,000 (3.5-4.1) in 2003 to 5.2 per 10,000 (4.8-5.5) in 2015. Mortality remained constant at 0.50 per 10,000 (0.39-0.62) in 2003 and 0.42 per 10,000 (0.32-0.51) in 2015. (4) Conclusions: CTPA increased from 2003 to 2015, while diagnostic yield decreased, potentially indicating overtesting. PE mortality remained constant despite increasing hospitalizations, likely indicating a higher proportion of less severe cases. As treatment can be harmful, this could represent overdiagnosis.

Use of CT, ED presentation and hospitalisations 12 months before and after a diagnosis of cancer in Western Australia: a population-based retrospective cohort study.

OBJECTIVE: To examine the use of CT, emergency department (ED)-presentation and hospitalisation and in 12 months before and after a diagnosis of cancer. DESIGN: Population-based retrospective cohort study. SETTING: West Australian linked administrative records at individual level. PARTICIPANTS: 104 009 adults newly diagnosed with cancer in 2004-2014. MAIN OUTCOME MEASURES: CT use, ED presentations, hospitalisations. RESULTS: As compared with the rates in the 12th month before diagnosis, the rate of CT scans started to increase from 2 months before diagnosis with an increase in both ED presentations and hospitalisation from 1 month before the diagnosis. These rates peaked in the month of diagnosis for CT scans (477 (95% CI 471 to 482) per 1000 patients), and for hospitalisations (910 (95% CI 902 to 919) per 1000 patients), and the month prior to diagnosis for ED (181 (95% CI 178 to 184) per 1000 patients) then rapidly reduced after diagnosis but remained high for the next 12 months. While the patterns of the health services used were similar between 2004 and 2014, the rate of the health services used during after diagnosis was higher in 2014 versus 2004 except for CT use in patients with lymphohaematopoietic cancer with a significant reduction. CONCLUSION: Our results showed an increase in demand for health services from 2 months before diagnosis of cancer. Increasing use of health services during and post cancer diagnosis may warrant further investigation to identify factors driving this change.

Patterns of computed tomography utilisation in injury management: latent classes approach using linked administrative data in Western Australia.

PURPOSE: Whilst computed tomography (CT) imaging has been a vital component of injury management, its increasing use has raised concern regarding ionising radiation exposure. This study aims to identify latent classes (underlying patterns) of CT use over a 3-year period following the incidence of injury and factors predicting the observed patterns. METHOD: A retrospective observational cohort study was conducted in 21,544 individuals aged 18 + years presenting to emergency departments (ED) of four tertiary public hospitals with new injury in Western Australia. Mixture modelling approach was used to identify latent classes of CT use over a 3-year period post injury. RESULTS: Amongst injured people with at least one CT scan, three latent classes of CT use were identified including a: temporarily high CT use (46.4%); consistently high CT use (2.6%); and low CT use class (51.1%). Being 65 + years or older, having 3 + comorbidities, history with 3 + hospitalisations and history of CT use before injury were associated with consistently high use of CT. Injury to the head, neck, thorax or abdomen, being admitted to hospital after the injury and arriving to ED by ambulance were predictors for the temporarily high use class. Living in areas of higher socio-economic disadvantage was a unique factor associated with the low CT use class. CONCLUSIONS: Instead of assuming a single pattern of CT use for all patients with injury, the advanced latent class modelling approach has provided more nuanced understanding of the underlying patterns of CT use that may be useful for developing targeted interventions.

Regularity of contact with general practitioners and diabetes-related hospitalisation through a period of policy change: A retrospective cohort study.

BACKGROUND: This study evaluated changes in regularity of general practitioner (GP) contact (the pattern of visits over time) and the impact of regularity on diabetes-related hospitalisation following introduction of care co-ordination incentives. METHODS: Linked primary care, hospital and death records covered West Australian adults from 1991-2004. Different eras were evaluated based on incentive program changes and model fit, to assess changes in regularity. Changes in regularity, derived from the variance in the number of days between GP contacts, were evaluated using ordered logistic regression. The impact of regularity on hospitalisation rates and costs were evaluated. RESULTS: Two eras prior to program introduction (1991/92-1994/9 and 1995/96-1998/99), and one after (1999/2000-2002/03) were assessed. Among 153,455 at risk of diabetes-related hospitalisation GP contact became slightly less regular in the second era, though there was no change from the second to third era. The most regular decile had 5.5% fewer hospitalisations (95% CI -0.9% to -9.9%) and lower per-patient costs (difference AU$115, CI -$63 to -$167) than the least regular. Associations were similar in each era. CONCLUSIONS: Ongoing relationships between GPs and patients are important to maintaining health. Historical data provide the opportunity to assess the impact of care co-ordination incentives on relationships.

Association of regulatory body actions and subsequent media coverage with use of services in a fee-for-service system: a longitudinal cohort study of CT scanning in Australia.

OBJECTIVE: The professional service review (PSR) is an Australian Government agency aiming to reduce inappropriate practices funded via Medicare, Australia's public insurer. Our objective was to examine changes in CT following the 2008-2009 PSR annual report, which noted excessive CT use. DESIGN: Interrupted time series analysis examined trends in CT use following the 2008-2009 PSR report, estimating both change in the immediate rate of CT and the slope of the trend in usage postintervention. SETTING: Medicare-funded imaging (most out-of-hospital imaging) in Australia. PARTICIPANTS: Patients receiving Medicare-funded CT and other imaging. INTERVENTION: The 2008-2009 PSR report highlighted concerns regarding excessive CT use. Two providers were financially penalised for CT overuse with these cases detailed in the PSR report and highlighted in an associated Report to the Professions, distributed to 50 000 providers. Media articles on radiation risks followed. OUTCOMES: Quarterly rates of out-of-hospital CT, MRI (as a comparator), and all other Medicare-funded diagnostic imaging examinations 2001-2019. RESULTS: CT scanning increased from 4663.5 per 100 000 person-years in 2001 to 14 506 in 2019 (211% increase), with substantial variation by type and anatomical region. The 2008-2009 PSR report was followed by an immediate reduction in CT scanning of 237.7 CTs per 100 000 people per quarter (95% CI -333.4 to -141.9) though growth in use soon continued at the preintervention rate. The degree of change in utilisation following the report differed between states/territories and by scan type, both in terms of the immediate change and the slope. For other diagnostic imaging modalities, there was an increase in the slope, while for MRI there was no change in either parameter. CONCLUSION: Actions consisting of financial disincentives for service overtesting and provider/public education components may limit excessive use of diagnostic imaging in fee-for-service systems, however, effects observed here were only short lived.

Trend in CT utilisation and its impact on length of stay, readmission and hospital mortality in Western Australia tertiary hospitals: an analysis of linked administrative data 2003-2015.

OBJECTIVE: High use of CT scanning has raised concern due to the potential ionising radiation exposure. This study examined trends of CT during admission to tertiary hospitals and its associations with length of stay (LOS), readmission and mortality. DESIGN: Retrospective observational study from 2003 to 2015. SETTING: West Australian linked administrative records at individual level. PARTICIPANTS: 2 375 787 episodes of tertiary hospital admission in adults aged 18+ years. MAIN OUTCOME MEASURES: LOS, 30-day readmissions and mortality stratified by CT use status (any, multiple (CTs to multiple areas during episode), and repeat (repeated CT to the same area)). METHODS: Multivariable regression models were used to calculate adjusted rate of CT use status. The significance of changes since 2003 in the outcomes (LOS, 30-day readmission and mortality) was compared among patients with specific CT imaging status relative to those without. RESULTS: Between 2003 and 2015, while the rate of CT increased 3.4% annually, the rate of repeat CTs significantly decreased -1.8% annually and multiple CT showed no change. Compared with 2003 while LOS had a greater decrease in those with any CT, 30-day readmissions had a greater increase among those with any CT, while the probability of mortality remained unchanged between the any CT/no CT groups. A similar result was observed in patients with multiple and repeat CT scanning, except for a significant increase in mortality in the recent years in the repeat CT group. CONCLUSION: The observed pattern of increase in CT utilisation is likely to be activity-based funding policy-driven based on the discordance between LOS and readmissions. Meanwhile, the repeat CT reduction aligns with a more selective strategy of use based on clinical severity. Future research should incorporate in-hospital and out-of-hospital CT to better understand overall CT trends and potential shifts between settings over time.

The use of computed tomography in the management of injury in tertiary emergency departments in Western Australia: Evidence of overtesting?

BACKGROUND: This study investigated trends in computed tomography (CT) utilization across different triage categories of injury presentations to tertiary emergency departments (EDs) and associations with diagnostic yield measured by injury severity, hospitalization and length of stay (LOS), and mortality. METHODS: A total of 411,155 injury-related ED presentations extracted from linked records from Western Australia from 2004 to 2015 were included in the retrospective study. The use of CT scanning and diagnostic yield measured by rate of diagnosis with severe injury, hospitalizations and LOS, and mortality were captured annually for injury-related ED presentations. Multivariable regression models were used to calculate the annual adjusted rate of CT scanning for injury presentations and hospitalizations across triage categories, diagnosis with severe injury, LOS, and mortality. The significance of changes observed was compared among patients with CT imaging relative to those without CT. RESULTS: While the number of ED presentations with injury increased by 65% from 2004 to 2015, the use of CT scanning in these presentations increased by 176%. The largest increase in CT use was among ED presentations triaged as semi-/nonurgent (+256%). Injury presentations with CT, compared to those without, had a higher rate of diagnosis with moderate/severe injury and hospitalization but no difference in LOS and mortality. The probability/rate observed in the outcomes of interest had a greater decrease over time in those with CT scanning compared with those without CT scanning across triage categories. CONCLUSIONS: The reduction in diagnostic yield in terms of injury severity and hospitalization found in our study might indicate a shift toward overtesting using CT in ED for injury or a higher use of CT to assist in the management of injuries. This helps health care policymakers consider whether the current increase in CT use meets the desired levels of quality and efficient care.

Associations between regular GP contact, diabetes monitoring and glucose control: an observational study using general practice data.

OBJECTIVE: Continuity and regularity of general practitioner (GP) contacts are associated with reduced hospitalisation in type 2 diabetes (T2DM). We assessed associations of these GP contact patterns with intermediate outcomes reflecting patient monitoring and health. DESIGN: Observational longitudinal cohort study using general practice data 2011-2017. SETTING: 193 Australian general practices in Western Australia and New South Wales participating in the MedicineInsight programme run by NPS MedicineWise. PARTICIPANTS: 22 791 patients aged 18 and above with T2DM. INTERVENTIONS: Regularity was assessed based on variation in the number of days between GP visits, with more regular contacts assumed to indicate planned, proactive care. Informational continuity (claims for care planning incentives) and relational continuity (usual provider of care index) were assessed separately. OUTCOME MEASURES: Process of care indicators were glycosylated haemoglobin (HbA1c) test underuse (8 months without test), estimated glomerular filtration rate (eGFR) underuse (14 months) and HbA1c overuse (two tests within 80 days). The clinical indicator was T2DM control (HbA1c 6.5% (47.5 mmol/mol)-7.5% (58.5 mmol/mol)). RESULTS: The quintile with most regular contact had reduced odds of HbA1c and eGFR underuse (OR 0.74, 95% CI 0.67 to 0.81 and OR 0.78, 95% CI 0.70 to 0.86, respectively), but increased odds of HbA1c overuse (OR 1.20, 95% CI 1.05 to 1.38). Informational continuity was associated with reduced odds of HbA1c underuse (OR 0.53, 95% CI 0.49 to 0.56), reduced eGFR underuse (OR 0.62, 95% CI 0.58 to 0.67) and higher odds of HbA1c overuse (OR 1.48, 95% CI 1.34 to 1.64). Neither had significant associations with HbA1c level. Results for relational continuity differed. CONCLUSIONS: This study provides evidence that regularity and continuity influence processes of care in the management of patients with diabetes, though this did not result in the recording of HbA1c within target range. Research should capture these intermediate outcomes to better understand how GP contact patterns may influence health rather than solely assessing associations with hospitalisation outcomes.