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Production of physician services under fee‐for‐service and blended fee‐for‐service: Evidence from Ontario, Canada

Abstract We examine family physicians’ responses to financial incentives for medical services in Ontario, Canada. We use administrative data covering 2003–2008, a period during which […]

Patient frailty predicts worse perioperative outcomes and higher cost after radical cystectomy

Abstract Background Relatively few studies investigated the importance of frailty in radical cystectomy (RC) patients. We tested the ability of frailty, using the Johns Hopkins […]

Patient-reported symptoms following diagnosis in esophagus cancer patients treated with palliative intent

Summary The majority of patients with esophagus cancer have advanced-stage disease without curative options. For these patients, treatment is focused on improving symptoms and quality […]

Peri‐complication diagnosis of hepatitis C infection: Risk factors and trends over time

Abstract Background & Aims Hepatitis C virus (HCV) is a common and treatable cause of cirrhosis and its complications, yet many chronically infected individuals remain […]

Using Health Plan Authorization Data to Predict Hospitalizations and Readmissions in a Combined Commercial and Medicaid Population

Abstract Health plans develop predictive models to predict key clinical events (eg, admissions, readmissions, emergency department visits). The authors developed predictive models of admissions and […]

Association between socioeconomic deprivation and surgical complications in adults undergoing ankle fracture fixation: a population-based analysis

Abstract Background Few studies have investigated the outcomes of surgical fracture care among socially deprived patients despite the increased incidence of fractures and the inequality […]

Breast cancer diagnosis and treatment wait times in specialized diagnostic units compared with usual care: a population-based study

Abstract Background Breast assessment sites (bass) were developed to provide expedited and coordinated care for patients being evaluated for breast cancer (bca) in Ontario. We […]

Epidemiology and Impact of Spinal Cord Injury in the Elderly: Results of a Fifteen-Year Population-Based Cohort Study

Abstract Objective Although experience suggests a shift in the epidemiology of spinal cord injury (SCI) toward an older demographic, population studies are lacking. We aimed […]

Systematic review on the instruments used for measuring the association of the level of multimorbidity and clinically important outcomes

ABSTRACT Objectives There are multiple instruments for measuring multimorbidity. The main objective of this systematic review was to provide a list of instruments that are […]

Inequities in access to primary care among opioid recipients in Ontario, Canada: A population-based cohort study

Abstract Background Stigma and high-care needs can present barriers to the provision of high-quality primary care for people with opioid use disorder (OUD) and those […]

Prevalence, determinants, and outcomes of SARS-COV-2 infection among cancer patients. A population-based study in northern Italy

Abstract Background It is well established that cancer patients infected with SARSCoV-2 are at particularly elevated risk of adverse outcomes, but the comparison of SARS-CoV-2 […]

Outcomes after the regionalization of care for high-grade endometrial cancers: a population-based study

Abstract Background In June 2013, Ontario Health (Cancer Care Ontario), the agency responsible for advancing cancer care in Ontario, Canada, published practice guidelines recommending that […]

Pre-operative wait times in high-grade non-endometrioid endometrial cancer: Do surgical delays impact patient survival?

Abstract Objective Practice guidelines advocating for regionalization of endometrial cancer surgery to gynecologic oncologists practicing in designated gynecologic oncology centres were published in Ontario in […]

Patterns Of Multimorbidity Of Patients In Geriatric Care – A Register-Based Cohort Study In Sweden

Abstract Background Patients in geriatric care display a high degree of multimorbidity. We aimed to explore and visualise various patterns of multimorbidity in a person-oriented […]

Impact of Social Needs in Electronic Health Records and Claims on Health Care Utilization and Costs Risk-Adjustment Models Within Medicaid Population

Abstract Patients enrolled in Medicaid have significantly higher social needs (SNs) than others. Using claims and electronic health records (EHRs) data, managed care organizations (MCOs) […]

Creating a Cost-map From Claims Data to Guide Improvement Actions for Children With Asthma

Abstract Purpose It is difficult to reduce cost and improve quality without knowledge pertaining to the distribution of expenses in the population in question. We […]

Effect of sustained virologic response on liver-related mortality among individuals living with hepatitis C by treatment era: A population-based retrospective cohort study

Abstract Purpose Sustained virologic response (SVR) is a validated surrogate marker for successful hepatitis C virus (HCV) treatment. Historically, interferon-based therapies, the standard of care […]

Risk Profile of Young Adults with Chronic Obstructive Pulmonary Disease

Abstract Background: COPD risk profiles have been described in populations comprised of or including older adults, leaving factors associated with COPD in younger adults overlooked. […]

Improving Prediction of Risk of Admission to Long-Term Care or Mortality Among Home Care Users With IDD

ABSTRACT Background Frailty is an established predictor of admission into long-term care (LTC) and mortality in the elderly population. Assessment of frailty among adults with […]

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Case Finding and Population Profiling

This webinar focuses on a project undertaken in Slough Clinical Commissioning Group where information from the ACG System was used to profile the population of […]

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Leveraging Prescription Data to Derive Future Costs and Predictors Regarding Opioid Abuse Patients

Presented by: David Bodycombe, ScD, MSc

Director ACG System Research

This Webinar describes his study, which created and assessed three measures of high-risk opioid use, presents results supporting the utility of these measures, and describes how the resulting measures are being deployed within the ACG System. Learn More.

Risk prediction models to predict emergency hospital admission in community-dwelling adults: a systematic review

Med Care 52:751-756. Centre for Primary Care Research, Royal College of Surgeons in Ireland, Dublin, Ireland BACKGROUND: Risk prediction models have been developed to identify […]

Frequent attenders in general practice and immigrant status in Norway: A nationwide cross-sectional study

Scand J Prim Health Care 32:232-240. Department of Global Public Health and Primary Care, University of Bergen, Norway OBJECTIVE: To compare the likelihood of being […]

Drugs prescribed by general practitioners according to age, gender and socioeconomic status after adjustment for multimorbidity level

BMC Fam Pract 15:183. Department of Clinical Sciences in Malmö, Center for Primary Health Care Research, Lund University, Malmö, Sweden BACKGROUND: Age, gender and socioeconomic […]

Direct medical costs attributable to venous thromboembolism among persons hospitalized for major operation: a population-based longitudinal study

Surgery 157:423-451. Mayo Clinic, Rochester, MN, USA; K Long Health Economics Consulting LLC, St. Paul, MN, USA BACKGROUND: We estimated medical costs attributable to venous […]

Preventive counseling services during primary care visits: a comparison of health centers versus other physician offices

J Health Care Poor Underserved 26:519-535. Johns Hopkins University, Baltimore, MD, USA We compared preventive counseling services provided by health centers versus other physician offices. […]

A comprehensive assessment of family physician gender and quality of care: a cross-sectional analysis in Ontario, Canada

Med Care 54:277-286. University of Ottawa, Ottawa, ON, Canada; Institute of Clinical Evaluative Sciences, Ottawa, ON, Canada; Queen’s University, Kingston, ON, Canada; Monash University, Clayton, […]

Prescription stimulant use and hospitalization for psychosis or mania: a population-based study

J Clin Psychopharmacol 35:667-671. Institute for Clinical Evaluative Sciences, Toronto, ON, Canada; University of Toronto, Toronto, ON, Canada; St Michael’s Hospital, Toronto, ON, Canada Small […]

Risk of cardiovascular events and mortality among a population-based cohort of immigrants and long-term residents with diabetes: Are all immigrants healthier and if so, for how long?

Am Heart J 170:123-132. University Health Network, Toronto, ON, Canada; Mount Sinai Hospital, Toronto, ON, Canada; Institute for Clinical Evaluative Sciences, Toronto, ON, Canada; University […]

Pain among older adults from a gender perspective: findings from the Swedish National Study on Aging and Care (SNAC-Blekinge)

Scand J Public Health Blekinge Institute of Technology, Karlskrona, Sweden; Lund University, Lund, Sweden; Linnaeus University, Växjö, Sweden BACKGROUND AND AIMS: Pain is common in […]

Ethnic disparities in care following acute coronary syndromes among Asian Americans and Pacific Islanders during the initial hospitalization

Cell Mol Biol 47:1209-1215. Hawaii Medical Service Association, Care Management, Honolulu, HI, USA Despite the fact that Asian Americans and Pacific Islanders are the fastest […]

Changes in health care costs over time following the cessation of intimate partner violence

J Gen Intern Med 25:920-925. Group Health Research Institute, Seattle, WA, USA BACKGROUND: Research has documented greater health care costs attributable to intimate partner violence […]

Universal health insurance and equity in primary care and specialist office visits: a population-based study

Ann Fam Med 7:396-405. Institute for Clinical Evaluative Sciences, Toronto, ON, Canada PURPOSE: Universal coverage of physician services should serve to reduce socioeconomic disparities in […]

Geographic variation in primary care visits in Iowa.

Health Serv Res 30:657-671. Graduate Program in Hospital and Health Administration, University of Iowa, Iowa City, IA, USA. OBJECTIVE: This study investigates the determinants of […]

Coding algorithms for defining comorbidities in ICD-9-CM and ICD-10 administrative data

Med Care 43:1130-1139. Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada OBJECTIVES: Implementation of the International Statistical Classification of Disease and Related […]

Epidemiology and impact of multimorbidity in primary care: a retrospective cohort study

Br J Gen Pract 61:e12-e21. Department of Community Medicine, University of Bristol, Bristol, UK BACKGROUND: In developed countries, primary health care increasingly involves the care […]

Predictive modeling in practice: improving the participant identification process for care management programs using condition-specific cut points

Popul Health Manag 14:205-210. Research and Development Unit, Johns Hopkins HealthCare LLC, Glen Burnie, MD, USA The objective of this study was to optimize predictive […]

Fracture risk from psychotropic medications: a population-based analysis

J Clin Psychopharmacol 28:384-391. Department of Psychiatry, University of Manitoba, Winnipeg, MB, Canada BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs), benzodiazepines, and antipsychotics have each been […]

Ankle fractures do not predict osteoporotic fractures in women with or without diabetes

Osteoporos Int 23:957-962. Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada It is not clear whether ankle fractures predict future osteoporotic fractures in women, […]

The role of provider continuity in preventing hospitalizations

Arch Fam Med 7:352-357. Department of Family and Community Medicine, Christiana Care Health System, Wilmington, DE, USA OBJECTIVES: To examine the association between provider continuity […]

The effect of distance to primary care physician on health care utilization and disease burden

Health Care Manage Rev 32:22-29. University of Michigan Medical School, Ann Arbor, USA. BACKGROUND: The relationship of distance to care with total health care utilization […]

Case mix measures for ambulatory care

J Public Health Med 13:189-197. University of Newcastle upon Tyne, School of Health Care Sciences, Medical School, Newcastle, UK Resource management in Ambulatory Care is […]

Performance of diagnosis-based risk adjustment measures in a population of sick Australians

Aust N Z J Public Health 26:500-507. Faculty of Health Sciences, School of Public Health, La Trobe University, Victoria, Australia OBJECTIVE: Australia is beginning to […]

Morbidity profiles at three primary care clinics in Perlis, Malaysia

Med J Malaysia 67:363-368. Ministry of Health, Kangar Health Clinic, Jalan Kolam, Kangar, Perlis, Malaysia Allocation of funding within the Ministry of Health of Malaysia […]

Healthcare utilization in patients with Parkinson’s disease: a population-based analysis

Parkinsonism Relat Disord 18:930-935. Movement Disorder Clinic, 200 Woodlawn Street, Winnipeg, MB, Canada PURPOSE: To investigate factors associated with healthcare utilization and prescription drug use […]

Referral of children to specialists in the United States and the United Kingdom

Arch Pediatr Adolesc Med 157:279-285. Department of Health Policy and Management, Health Services Research and Development Center, Bloomberg School of Public Health, Johns Hopkins University, […]

Is quality free? The relationship between cost and quality across 18 provider groups

Am J Manag Care 8:413-422. HealthPartners Research Foundation, Minneapolis, MN, USA OBJECTIVE: To learn whether the healthcare costs for patients of various care delivery systems […]

A patient classification system for our primary care: the Ambulatory Care Groups (ACGs)

Gac Sanit 11:83-94. Published in Spanish. Unitat d’Investigació Centre del Institut Catalá de la Salut, Barcelona, Spain OBJECTIVES: The ambulatory care groups (ACGs) were developed […]

Influence of morbidity, metabolic control, and use of resources in subjects with cardiovascular risk in the primary care setting

Aten Primaria 40:447-454. Published in Spanish. Dirección de Planificación y Desarrollo Organizativo. Badalona Serveis Assistencials S.A. Badalona. Barcelona. España OBJECTIVE: To determine the comorbidity, the […]

Complexity and continuity of treatments among privately insured youth diagnosed with bipolar disorder

Front Psychiatry 1:144. Health Services and Population Research Department, Institute of Psychiatry, King’s College London, London, UK OBJECTIVES: To examine longitudinal patterns of complexity, continuity, […]

Cognitive and behavioral outcomes after early exposure to anesthesia and surgery

Pediatrics 128:e1053-e1061. Erratum in: Pediatrics. 2012 Mar;129(3):595. Department of Anesthesiology, College of Medicine, Mayo Clinic, Rochester, MN, USA BACKGROUND: Annually, millions of children are exposed […]

Use and costs of medical care for children and adolescents with and without attention-deficit/hyperactivity disorder

JAMA 285:60-66. Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA CONTEXT: A shortage of data exists on medical care use by persons with […]

Use of other opioids during methadone therapy: a population-based study

Addiction 107:776-780. Institute for Clinical Evaluative Sciences, Toronto, ON, Canada AIMS: To determine the extent to which other opioids are prescribed to patients receiving methadone […]

Adaptive capacity of the Adjusted Clinical Groups Case-Mix System to the cost of primary healthcare in Catalonia (Spain): a observational study

BMJ Open 2:2012-000941. Directorate of Planning, Badalona Serveis Assistencials SA, Badalona, Barcelona, Spain OBJECTIVES: To describe the adaptive capacity of the Adjusted Clinical Groups (ACG) […]

Estimating diabetes prevalence in the Military Health System population from 2006 to 2010

Mil Med 178:986-993. Healthcare Informatics Division, United States Air Force Medical Support Agency, San Antonio, TX, USA Evidence-based articles have demonstrated an increase in diabetes […]

Glycemic control associated with secure patient-provider messaging within a shared electronic medical record: a longitudinal analysis

Diabetes Care 36:2726-2733. University of Washington School of Public Health, Seattle, WA, USA; Harvard School of Public Health, Boston, MA, USA; Group Health Research Institute, […]

Direct health-care costs attributed to hip fractures among seniors: a matched cohort study

Osteoporos Int 24:659-669. Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada SUMMARY: Using a matched cohort design, we estimated the mean direct […]

Predictors of dislocation and revision after shoulder stabilization in Ontario, Canada, from 2003 to 2008

Am J Sports Med 41:2034-2040. University of Toronto Orthopaedic Sports Medicine, Women’s College Hospital, Toronto, ON, Canada BACKGROUND: Factors contributing to recurrent dislocation, revision stabilization, […]

Estimating Demand for Care After a Medicaid Expansion: Lessons From Oregon

J Ambul Care Manage. Kaiser Permanente Northwest Center for Health Research, Portland, OR; Oregon Health and Science University, Portland, OR, USA To estimate how the […]

Characteristics of adult primary care patients as predictors of future health services charges

Med Care 39:1170-1181. Department of Community and Family Medicine, Duke University Medical Center, Durham, NC, USA BACKGROUND: Utilization risk assessment is potentially useful for allocation […]

The patient-centered medical home, electronic health records, and quality of care

Ann Intern Med 160:741-749. Weill Cornell Medical College, New York, NY, USA BACKGROUND: The patient-centered medical home (PCMH) model of primary care is being implemented […]

Relationship between pain and quality of life – findings from the Swedish National Study on Aging and Care – Blekinge study

Scand J Pain 5:270-275. Blekinge Institute of Technology, Karlskrona, Sweden; Lund University, Lund, Sweden; Linnaeus University, Växjö, Sweden BACKGROUND AND AIMS: The influence of pain […]

MEDS-AD Waiver (MTM) Program final report

Prepared for Florida Medicaid. Tallahassee, FL, USA: College of Medicine, Florida State University. Florida State University, Tallahassee, FL, USA This report summarizes the final findings […]

Change in functional outcomes during inpatient rehabilitation for patients with hypoxic-ischemic brain injury

Arch Phys Med Rehabil 96:e18. Toronto Rehabilitation Institute, Toronto, ON, Canada Objective(s): To investigate determinants of change in functional outcomes during inpatient rehabilitation (IR) among […]

Performance of an ambulatory case-mix measurement in primary care in Spain: Ambulatory Care Groups (ACGs)

Eur J Public Health 9:27-35. Unitat d’Investigació Centre del Institut Catalá de la Salut, Barcelona, Spain BACKGROUND: Patient classification systems based on the defining of […]

ACG use in Veterans Administration in Taiwan: final report

Taipei, Taiwan: Veterans General Hospital Taipei. Published in Chinese. Department of Medical Affairs and Planning, Taipei Veterans General Hospital, Taipei City, Taiwan, ROC The goal […]

Sex differences in health status, health care use and quality of care: a population-based analysis for Manitoba’s regional health authorities

Winnipeg, MB, Canada: Manitoba Centre for Health Policy. Manitoba Centre for Health Policy, Department of Community Health Sciences, Faculty of Medicine, University of Manitoba, Winnipeg, […]

A comparison of alternative approaches to risk measurement

Final report, grant number 93-G07, Physician Payment Review Commission. Minneapolis, MN, USA: Park Nicollet Medical Foundation. Park Nicollet Medical Foundation, Minneapolis, MN, USA Under health […]

ACGs: ambulatory care groupings for case-mix categorization

Final report for grant #HS05505, National Center for Health Care Research/Health Care Technology Assessment. Baltimore, MD, USA: Johns Hopkins University. Johns Hopkins University, Baltimore, MD, […]

CYDL Project One summary report: experiences of Albertan youth 2008/2009

Child and Youth Data Laboratory. Edmonton, AB, Canada: Centre for Child, Family and Community Research. Site also has videos of presentations of report data. Centre […]

A study of population needs-based funding applied to health care and physician services in British Colulmbia

Vancouver, BC, Canada: University of British Columbia (masters thesis). University of British Columbia, Vancouver, BC, Canada The BC Ministry of Health has developed a Population […]

Evaluation of the Medicaid Value Program: health supports for consumers with chronic conditions

Hamilton, NJ, USA: Center for Health Care Strategies. Center for Health Care Strategies, Hamilton, NJ, USA The Center for Health Care Strategies’ (CHCS) Medicaid Value […]

Chapter 5: Antihypertensive adherence and drug class among Asian Pacific Americans

In: Bateman WB – Abesamis-Mendoza J – Ho-Asjoe H – ed. Praeger handbook of Asian-American health: taking notice and taking action. Santa Barbara CA USA: […]

Adherence with lipid-lowering, antihypertensive, and diabetes medications

Am J Pharm Benefits 3:165-171. Hawaii Medical Service Association, Honolulu, HI, USA OBJECTIVES: To investigate the combinations of medications patients were taking, the study examined […]

Adaptation of the categories Johns-Hopkins ACG Case-Mix System in primary healthcare: a longitudinal, retrospective claim database study

WebmedCentral ECONOMICS OF MEDICINE 2:WMC001657. Directorate of Planning, Badalona Serveis Assistencials SA, Badalona, Spain BACKGROUND: To determine the adaptation capacitating of categories case-mix adjustment (Adjusted […]

Comparing the costs and use of services in TRICARE Prime with employer sponsored insurance

Orlando, FL, USA: AcademyHealth Annual Research Meeting. NORC at the University of Chicago, Bethesda, MD, USA RESEARCH OBJECTIVE: The objectives are: to compare the cost […]

The trend of prevalence of multimorbidity and needs of out-patient health care services in rural and urban areas in Klaipeda region

Health Sci 23:173-178. Published in Lithuanian. The aim of the study: to evaluate multimorbidity dynamics, and needs of out-patient health care services in rural and […]

Predicting the Cost of Health Care Services

Abstract   Background: Case-mix systems and comorbidity indices aggregate clinical information about patients over time and are used to characterize need for health care services. […]

Data Validation

DST Health Solutions Data Validation Sokchay Chiv

Monday(C1)-Persistent High Users Characteristics and Identification-Chang

Persistent High Users Characteristics and Identification-Hsien-Yen Chang PhD 

Monday(P4)-The association between expenditures and quality in type 2 diabetes mellitus care

The association between expenditures and quality in type 2 diabetes mellitus care  Troels Kristensena, Msc, PhD, Kim Rose-Olsena, Msc, PhD  Charlotte Ejersted, MD., PhD  Anders […]

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Research and publications utilizing the ACG System

Chris Forrest, MD, PhD, Professor of Pediatrics and Health Care Management, University of Pennsylvania and Children’s Hospital of Philadelphia, and ACG System co-developer discusses how […]

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Population Health Management through Care Coordination and Interventions

Population health management at JHHC represents a comprehensive approach to health care considering the distribution of health outcomes within a population, and the health determinants […]

Predictors of hospital stay and home care services use: A population-based, retrospective cohort study in stage IV gastric cancer

Background: Home care services use has been proposed as a means of reducing costs in palliative care by decreasing hospital stay without impacting quality of […]

Albuminuria, Reduced Kidney Function, and the Risk of ST‐ and non–ST‐segment–elevation myocardial infarction

Abstract Background Chronic kidney disease is a recognized independent risk factor for cardiovascular disease, but whether the risks of ST‐segment–elevation myocardial infarction (STEMI) and non–ST‐segment–elevation […]

Correlation between Potentially Inappropriate Medication and Alzheimer’s Disease among the Elderly

Abstract   Purpose This study is conducted to explore the association between potentially inappropriate medication (PIM) and Alzheimer’s disease (AD) among the elderly. Methods We […]

Variation in the health outcomes associated with frailty among home care clients: relevance of caregiver distress and client sex

Abstract Background The identification of contextual factors that modify associations between client frailty and their health and service use outcomes is essential for informed home […]

The Incremental Health Care Costs of Frailty Among Home Care Recipients With and Without Dementia in Ontario, Canada: A Cohort Study

Abstract Objective In this study, we investigated the incremental 1-year direct costs of health care associated with frailty among home care recipients in Ontario with and without […]

Do Incentive Payments Reward The Wrong Providers? A Study Of Primary Care Reform In Ontario, Canada

ABSTRACT Primary care payment reform in the US and elsewhere usually involves capitation, often combined with bonuses and incentives. In capitation systems, providing care within […]

Economic Analysis of Adjuvant Chemoradiotherapy Compared with Chemotherapy in Resected Pancreas Cancer

Abstract Background Population-based survival and costs of pancreas adenocarcinoma patients receiving adjuvant chemoradiation and chemotherapy following pancreaticoduodenectomy are poorly understood. Methods This retrospective cohort study used […]

Incremental healthcare utilisation and costs among new senior high-cost users in Ontario, Canada: a retrospective matched cohort study

Abstract Objectives To describe healthcare use and spending before and on becoming a new (incident) senior high-cost user (HCU) compared with senior non-HCUs; to estimate […]

Diagnostic accuracy of administrative codes for autosomal dominant polycystic kidney disease in clinic patients with cystic kidney disease

Abstract Background The ability to identify patients with autosomal dominant polycystic kidney disease (ADPKD) and distinguish them from patients with similar conditions in healthcare administrative […]