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Development and application of a population-oriented measure of ambulatory care case-mix

Med Care 29:452-472. Department of Health Policy and Management, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD, USA This article describes a […]

Adjusted Clinical Groups (ACGs) explain the utilization of primary care in Spain based on information registered in the medical records: a cross-sectional study

Health Policy 76:38-48. Centro de Salud Astrabudua, Consulado Bilbao, Bizkaia, Spain BACKGROUND: Previous studies have shown the validity of Adjusted Clinical Groups (ACGs) in the […]

Diabetes quality of care and outpatient utilization associated with electronic patient-provider messaging: a cross-sectional analysis

Diabetes Care 32:1182-1187. Department of Health Services, University of Washington School of Public Health and Community Medicine, Seattle, WA, USA OBJECTIVE: To test the hypothesis […]

Imputation of 10-year osteoporotic fracture rates from hip fractures: a clinical validation study.

J Bone Miner Res 25:388-392. Faculty of Medicine, University of Manitoba, Winnipeg, MB, Canada The World Health Organization (WHO) fracture risk assessment system (FRAX) allows […]

Differences in referral rates to specialised health care from four primary health care models in Klaipeda, Lithuania

BMC Fam Pract 9:63. Lund University, Department of Clinical Sciences in Malmö, General Practice/Family Medicine, Malmö, Sweden BACKGROUND: Lithuanian primary health care (PHC) is undergoing […]

Managing the gap: evaluating the impact of Medicaid managed care on preventive care receipt by child and adolescent minority populations

J Health Care Poor Underserved 21:92-111. St. Mary’s College of Maryland, St. Mary’s City, MD, USA The increased use of managed care in Medicaid warrants […]

Patient web services integrated with a shared medical record: patient use and satisfaction

J Am Med Inform Assoc 14:798-806. Center for Health Studies, Group Health Cooperative, Seattle, WA, USA OBJECTIVES: This study sought to describe the evolution, use, […]

Using the Johns Hopkins’ Aggregated Diagnosis Groups (ADGs) to predict 1-year mortality in population-based cohorts of patients with diabetes in Ontario, Canada

Diabet Med 29:1134-1141. Institute for Clinical Evaluative Sciences, University of Toronto, ON, Canada AIMS: There are limited validated methods to ascertain comorbidities for risk adjustment […]

Quantifying morbidity burdens and medical utilization of children with intellectual disabilities in Taiwan: A nationwide study using the ACG case-mix adjustment system

Res Dev Disabil 33:1270-1278. Department of Medical Affairs and Planning, Taipei Veterans General Hospital, Taipei City, Taiwan, ROC The purpose of this study was to […]

Is it necessary that some patients come to see us so often? Factors associated with primary care use in pediatrics

Gac Sanit 14:195-202. Published in Spanish. Centro de Salud de Astrabudúa (Bizkaia), Osakidetza-Servicio Vasco de Salud, Bilbao, Spain OBJECTIVES: To analyze the relationship between pediatric […]

Development of a claims-based risk score to identify obese individuals

Popul Health Manag 13:201-207. Division of General Internal Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA Obesity is underdiagnosed, hampering system-based health promotion […]

Comparison of health care expenditures among insured users and nonusers of complementary and alternative medicine in Washington State: a cost minimization analysis

J Altern Complement Med 16:411-417. Department of Health Services, University of Washington, Seattle, WA, USA OBJECTIVES: The purpose of this analysis was to compare health […]

Guided care: cost and utilization outcomes in a pilot study

Dis Manag 11:29-36. Johns Hopkins HealthCare, Glen Burnie, MD, USA Guided Care (GC) is an enhancement to primary care that incorporates the operative principles of […]

Identifying frail older people using predictive modeling

Am J Manag Care 18:e392-e397. Department of Geriatric Medicine, Maccabi Healthcare Services, Tel Aviv, Israel OBJECTIVES: To determine whether a designation of frailty using the […]

A randomized study to decrease the use of potentially inappropriate medications among community-dwelling older adults in a southeastern managed care organization

Am J Manag Care 10:761-768. Department of Medicine and Center for Healthcare Improvement, Medical College of Georgia, Atlanta, Ga, USA BACKGROUND: Despite progress in describing […]

Development and validation of a model for predicting inpatient hospitalization

Med Care 50:131-139. Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health and School of Medicine, Baltimore, MD, USA BACKGROUND: Hospitalizations […]

Involuntary unemployment and mortality in Taiwan

J Formos Med Assoc 103:900-907. Institute of Public Health, National Yang-Ming University, Taipei, Taiwan. BACKGROUND AND PURPOSE: Unemployment is known to be associated with increased […]

Case-control study of antibiotic use and subsequent Clostridium difficile-associated diarrhea in hospitalized patients

Infect Control Hosp Epidemiol 29:44-50. Permanente Medical Group, Oakland, CA, USA OBJECTIVE: To determine which antibiotics increase or decrease the risk of Clostridium difficile-associated diarrhea […]

More preventive care, and fewer emergency room visits and prescription drugs–health care utilization in a consumer-driven health plan

Benefits Q 24:46-54. Healthcare Informatics, Blue Cross Blue Shield of Minnesota, USA. Although consumer-driven health plans (CDHPs) have grown dramatically, the question of whether CDHPs […]

Assessing comorbidity using claims data: an overview

Med Care 40:IV-26-IV-35. Health Services and Economics Branch, Applied Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, MD, USA Comorbidity, […]

Pharmacy- and diagnosis-based risk adjustment for children with Medicaid

Med Care 43:1155-1159. Center for Child and Adolescent Health Policy, MassGeneral Hospital for Children, Department of Pediatrics, Harvard Medical School, Boston, MA, USA BACKGROUND: Risk […]

The influence of incidental abdominal aortic aneurysm monitoring on patient outcomes

J Vasc Surg 54:1290-1297.e2. Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada BACKGROUND: Incidental abdominal aortic aneurysms (AAAs) are identified when the abdomen is […]

Population based study of long-term rates of surgery for urinary incontinence after radical prostatectomy for prostate cancer

J Urol 188:502-506. Division of Urology, Sunnybrook Health Sciences Centre, Sunnybrook Research Institute, Toronto, ON, Canada PURPOSE: Urinary incontinence can be a significant complication of […]

Prescribing of psychotropic medications to the elderly population of a Canadian province: a retrospective study using administrative databases

PeerJ 1:e168. Faculty of Pharmacy, University of Manitoba , Winnipeg, MB, Canada BACKGROUND. Psychotropic medications, in particular second-generation antipsychotics (SGAs) and benzodiazepines, have been associated […]

Comparative safety and effectiveness of sitagliptin in patients with type 2 diabetes: retrospective population based cohort study

BMJ 346:f2267. Department of Public Health Sciences, School of Public Health, University of Alberta, Edmonton, AB, Canada OBJECTIVE: To determine if the use of sitagliptin […]

Association between fee-for-service expenditures and morbidity burden in primary care

Eur J Health Econ 15:599-610. Faculty of Health Sciences, COHERE-Centre of Health Economics Research, Institute of Public Health, University of Southern Denmark, Odense, Denmark BACKGROUND: […]

Using risk-adjustment models to identify high-cost risks

Med Care 41:1301-1312. Center for Health Research, Northwest and Hawaii, Kaiser Permanente Northwest, Portland, OR, USA BACKGROUND: We examine the ability of various publicly available […]

Predicting persistently high primary care use

Ann Fam Med 3:324-330. Division of Health Care Policy & Research, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, MN, USA PURPOSE: […]

Specialty use among patients with treated hypertension in a patient-centered medical home

J Gen Intern Med Division of General Internal Medicine and Geriatrics, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA BACKGROUND: Little is known about […]

One-year outcomes associated with using observation services in triaging patients with nonspecific chest pain

Clin Cardiol 37:591-596. Division of Management, Policy and Community Health, University of Texas School of Public Health, Houston, Texas. BACKGROUND: Observation services are provided in […]

Changes in office visit use associated with electronic messaging and telephone encounters among patients with diabetes in the PCMH

Ann Fam Med 12:338-343. Group Health Research Institute, Seattle, WA, USA PURPOSE: Telephone- and Internet-based communication are increasingly common in primary care, yet there is […]

Measuring morbidity in populations: performance of the Johns Hopkins Adjusted Clinical Group (ACG) case-mix adjustment system in Manitoba

Winnipeg, MB, Canada: Manitoba Centre for Health Policy. Manitoba Centre for Health Policy, Winnipeg, MB, Canada This study examined the performance of the Johns Hopkins […]

Creating meaningful composite scores for primary care

2015 North American Primary Care Research Group Annual Meeting, October 2015, Cancun, Mexico. Context: Composite scores (CSs) provide a global measure of quality. CS development […]

Long-term risk of heart failure associated with adjuvant trastuzumab in breast cancer patients

2014 American Society of Clinical Oncology Annual Meeting. Abstract 9504. J Clin Oncol 32 (suppl; abstr 9504). University of Toronto, Toronto, ON, Canada; St. Michael’s […]

Is the class half empty? A population-based perspective on socioeconomic status and educational outcomes

IRPP Choices 12:1-30. Manitoba Centre for Health Policy, Department of Community Health Sciences, Faculty of Medicine University of Manitoba, Winnipeg, MB, Canada The purpose of […]

Characteristics of risk adjustment systems. Working Paper Series 2

Gainesville, FL, USA: Institute for Child Health Policy, University of Florida. Institute for Child Health Policy, University of Florida, Gainesville, FL, USA Increasing numbers of […]

Using the ACG case-mix adjustment system to evaluate veteran’s morbidity burdens and medical utilizations in Taiwan

J Healthc Manag 8:67-84. Published in Chinese. Department of Medical Affairs and Planning, Taipei Veterans General Hospital, Taipei City, Taiwan, ROC OBJECTIVES: Veterans have been […]

Performance of risk adjusted capitated systems in allocating a global budget

Baltimore, MD, USA: Johns Hopkins University (doctoral dissertation). Johns Hopkins University, Baltimore, MD, USA Rapidly rising health care costs in the United States have led […]

The Adjusted Clinical Groups (ACGs) system in Osakidetza

Final report (1/05/2003 – 30/04/2003). Vitoria-Gasteiz, Spain: Osakidetza Servicio vasco de salud. Published in Spanish. Osakidetza Servicio vasco de salud, Vitoria-Gasteiz, Spain No abstract

How are Manitoba’s children doing?

Winnipeg, MB, Canada: Manitoba Centre for Health Policy. Manitoba Centre for Health Policy, Winnipeg, MB, Canada The health and development of Manitoba’s children were examined […]

Using selected diagnoses to improve the Chilean capitation formula

Greifswald, Germany: Ernst Moritz Arndt University of Greifswald. Ernst Moritz Arndt University of Greifswald, Greifswald, Germany OBJECTIVES: To contribute to the policy discussion of equity […]

Home health services in British Columbia: a portrait of users and trends over time

Home health services in British Columbia: a portrait of users and trends over time. Vancouver, BC, Canada: University of British Columbia. University of British Columbia, […]

The effect of a coordinated care program on uninsured, chronically ill patients

Richmond, VA, USA: Virginia Commonwealth University (doctoral dissertation). Virginia Commonwealth University, Richmond, VA, USA This study explored how being enrolled in a program that both […]

Equity in the use and financing of medicines in British Columbia before and after the move to income-based pharmacare

Vancouver, BC, Canada: University of British Columbia (doctoral dissertation). University of British Columbia, Vancouver, BC, Canada BACKGROUND: In May 2003, the B.C. government introduced an […]

Utilizacion de servicios de salud en atencion primaria del area 11 de Madrid y nivel psicobioquimico de estres y de salud bucodental en su poblacion immigrante y autoctona

Madrid, Spain: Universidad Complutense de Madrid (masters thesis). Published in Spanish. Universidad Computense de Madrid, Madrid, Spain La naturaleza trashumante de la Humanidad le es […]

Developing decision trees to classify patients suited for similar interventions by combining clinical judgments with Leeds Risk Stratification Tool

London, UK: London School of Economics and Political Science. London School of Economics and Political Science, London, UK The objectives of the project are to […]

What is most important: social factors, health selection, and adolescent educational achievement

Soc Indic Res 110:385-414. Department of Community Health Sciences, Faculty of Medicine, Manitoba Centre for Health Policy, University of Manitoba, Winnipeg, MB, Canada This paper […]

Case Finding & Population Profiling – Separate Disciplines or Both Sides of the Same Coin?

This award-winning document presented at the 2015 PCSI conference highlights work undertaken with Slough Clinical Commissioning Group in the UK. The work has challenged some […]

Leicester City CCG Case Study 2

 Use of ACG® System output to support practices in participating in a medicines management scheme – STOPP-START

Care Management Program Case Study-Payer

Clalit Health (an integrated delivery system in Israel) used the ACG System to identify high-risk patients for enrollment in a comprehensive complex care management program […]

Case-Mix Information Uses and Health Services Sustainability

Iasist Casemix Information Uses and Health Services Sustainability: A Few Examples From Current Spanish Downturn Mercè Casas Carles Illa

Options for Concurrent Risk Assessment

DST Health Solutions Options for Concurrent Risk Assessment Amy Salls

Monday(C2)-Steep Increase of Registered Diagnosis Due to New Primary Care Funding Model-Martin Fredriksson

Steep Increase of Registered Diagnosis Due to New Primary Care Funding Model —Martin Fredriksson Region Västra Götaland Medical Advisor at Healtcare Department M.D. Ph.D.

Wednesday(P4)-Population Health Emerging Risk-Medscheme

Population Health Emerging Risk-Medscheme

PREDICTING HEALTHCARE COSTS IN VENETO REGION WITH ACG SYSTEM: VALIDATION AND COMPARISON OF DIAGNOSIS-BASED AND DRUG-BASED MORBIDITY GROUPS IN A NORTHERN ITALIAN POPULATION 

F. Avossa, 1, M.C. Corti, 2 , E. Schievano1, C. Abrams, 3 , N. Alba,  4 , S. Elvini, 5 , P. Gallina,  5, C. […]

Cost Risk Scores: Amy Salls, DST Health Solutions

ACG System The Johns Hopkins ACG® System Cost Risk Models Amy Salls

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The ACG System and Public Health

Joshua Sharfstein, MD, Associate Dean of the Office of Public Health Practice & Training, Johns Hopkins Bloomberg School of Public Health and former Secretary of […]

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Provider Profiling and Engagement Case Study – Payer

Johns Hopkins HealthCare (JHHC), the managed care arm of Johns Hopkins, created Provider Profile reports leveraging outputs from the Johns Hopkins ACG System to build a comprehensive Provider Engagement program.

The uptake of active surveillance for the management of prostate cancer: A population-based analysis

Introduction: Active surveillance (AS) is a strategy for the management of low-risk prostate cancer (PCa). However, few studies have assessed the uptake of AS at […]

Apples and Oranges: Four Definitions of Multiple Chronic Conditions and their Relationship to 30-Day Hospital Readmission

Health Innovation Program, the University of Wisconsin School of Medicine and Public Health from The Wisconsin Partnership Program, and the Community–Academic Partnerships core of the […]

Primary care utilization in people who experience imprisonment in Ontario, Canada: a retrospective cohort study

Abstract Background Access to primary care is an important determinant of health, and data are sparse on primary care utilization for people who experience imprisonment. […]

Vulnerable And Less Vulnerable Women In High-Deductible Health Plans Experienced Delayed Breast Cancer Care

ABSTRACT The effects of high-deductible health plans (HDHPs) on breast cancer diagnosis and treatment among vulnerable populations are unknown. We examined time to first breast […]

Patient-reported symptoms after breast cancer diagnosis and treatment: A retrospective cohort study

Abstract Aim Breast cancer and its treatment are associated with varying symptoms. The province of Ontario (13.6 million) has implemented a provincial programme to screen for symptoms among […]

Performance on the Operant Test Battery in young children exposed to procedures requiring general anaesthesia: the MASK study

Abstract Background It is not known whether the neurotoxicity produced by anaesthetics administered to young animals can also occur in children. Exposure of infant macaques […]

Prevalence of intellectual and developmental disabilities among first generation adult newcomers, and the health and health service use of this group: A retrospective cohort study

Abstract Background Attention to research and planning are increasingly being devoted to newcomer health, but the needs of newcomers with disabilities remain largely unknown. This […]

Multimorbidity Patterns in Patients with Back Pain: A Study of Patient Records at a Primary Health Care Centre in Sweden

Abstract In Primary Care, multimorbidity is the norm in most patients. A large part of these have pain disorders, very often related to the spine. […]

Changes in primary care provider utilization by phase of care for women diagnosed with breast cancer: a CanIMPACT longitudinal cohort study

Abstract Background Primary care providers (PCPs) have always played an important role in cancer diagnosis. There is increasing awareness of the importance of their role […]

Does early palliative identification improve the use of palliative care services?

Abstract Purpose To evaluate whether the early identification of patients who may benefit from palliative care impacts on the use of palliative, community and acute-based […]

Predicting the Cost of Health Care Services : A Comparison of Case-mix Systems and Comorbidity Indices That Use Administrative Data

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. These […]

Use of administrative record linkage to measure medical and social risk factors for early developmental vulnerability in Ontario, Canada

Abstract Background Linkage of demographic, health, and developmental administrative data can enrich population-based surveillance and research on developmental and educational outcomes. Transparency of the record […]

Analysis of the relationship between surgeon procedure volume and complications after total knee arthroplasty using a propensity-matched cohort study

Abstract Objectives This study aimed to identify a threshold in annual surgeon volume associated with increased risk of revision (for any cause) and deep infection […]

Determinants of vaccination uptake, and influenza vaccine effectiveness in preventing deaths and hospital admissions in the elderly population; Treviso, Italy, 2014/2015-2016/2017 seasons

ABSTRACT Objective Seasonal influenza is an important cause of morbidity and mortality, particularly among the elderly population. Determinants of vaccination uptake and its impact on […]

Frailty impact on postoperative complications and early mortality rates in patients undergoing radical cystectomy for bladder cancer: a systematic review

Abstract Objective To assess the prevalence of frailty, a status of vulnerability to stressors leading to adverse health events, in bladder cancer patients undergoing radical […]

Medical use of cocaine and perioperative morbidity following sinonasal surgery—A population study

Abstract Background Topical cocaine is favoured by many surgeons for sinonasal surgery due to its superior vasoconstrictive and anesthetic properties. However, historical reports suggesting cocaine […]

Congestive heart failure and comorbidity as determinants of colorectal cancer perioperative outcomes

Abstract Objective There has been an increase in surgical interventions in frailer elderly with concomitant chronic diseases. The purpose of this paper was to evaluate […]

Real-world Safety of Bevacizumab with First-line Combination Chemotherapy in Patients with Metastatic Colorectal Cancer: Population-based Retrospective Cohort Studies in Three Canadian Provinces

Abstract Aims To examine the real-world safety of adding bevacizumab to first-line irinotecan-based chemotherapy for patients with metastatic colorectal cancer (mCRC). Materials and methods Patients diagnosed with CRC in […]

The receipt of information by family physicians about their patient’s emergency department visits: a record linkage study of electronic medical records to health administrative data

Abstract Background Canadians are known to be frequent users of emergency department (ED) care. However, the exchange of information from ED visits to family physicians […]

The effect of frailty on post-operative outcomes and health care expenditures in patients treated with partial nephrectomy

Abstract Objective To examine the effect of frailty on short-term post-operative outcomes and total hospital charges (THCs) in patients with non-metastatic renal cell carcinoma, treated […]

Improving patient well-being in the United States through care coordination interventions informed by social determinants of health

Abstract Health and well-being are promoted when primary care teams partner with patients and provide care coordination to mitigate risks and promote optimal health. Identification […]

Performance of administrative database frailty instruments in predicting clinical outcomes and cost for patients undergoing transcatheter aortic valve implantation: a historical cohort study

Abstract Purpose Frailty instruments may improve prognostic estimates for patients undergoing transcatheter aortic valve implantation (TAVI). Few studies have evaluated and compared the performance of […]

Predicting Provider Workload Using Predicted Patient Risk Score and Social Determinants of Health in Primary Care Setting

Abstract Background Provider burnout due to workload is a significant concern in primary care settings. Workload for primary care providers encompasses both scheduled visit care […]

Evaluating the impact of capitation funding top-up payments in primary care

Abstract Background Capitation payments account for approximately half of core funding for General Practitioner (GP) practices in England, allocated via the Global Sum Allocation (‘Carr-Hill’) […]

Longitudinal costs and health service utilisation associated with primary care reforms in Ontario: a retrospective cohort study protocol

ABSTRACT Introduction Over the last 20 years, the Canadian province of Ontario implemented several new models of primary care focusing on changes to physician remuneration, […]

Readmissions Infographic

Preventing avoidable hospital readmissions is considered by many to be the most important opportunity for reducing waste in health care.  The Johns Hopkins ACG® System can […]

Defining and Assessing Geriatric Risk Factors and Associated Health Care Utilization Among Older Adults Using Claims and Electronic Health Records

Abstract Background: Using electronic health records (EHRs), in addition to claims, to systematically identify patients with factors associated with adverse outcomes (geriatric risk) among older […]

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Supporting Clinical Activities

The ACG System UK Team hosts a series of webinars aimed at providing an overview on a number of topics related to risk stratification, population […]

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Predictive Modelling in Action

An introduction to the principles of predictive modeling in health care and examples of how predictive models are being used in the NHS in England. Learn more.

Do physicians who diagnose more mental health disorders generate lower health care costs?

J Fam Pract 49:305-310. University of Rochester School of Medicine, New York, NY, USA BACKGROUND: Underrecognition and undertreatment of mental health disorders in primary care […]

A cross-sectional, population-based study measuring comorbidity among people living with HIV in Ontario

BMC Public Health 14:161. Primary Health Care Research Centre, Bruyère Research Institute, Ottawa, ON, Canada BACKGROUND: As people diagnosed with HIV and receiving combination antiretroviral […]

Health information exchange and the frequency of repeat medical imaging

Am J Manag Care 20:eSP16-24. Weill Cornell Medical College, New York, NY, USA OBJECTIVES: Medical imaging, which is expensive, is frequently repeated for the same […]

Missed strokes using computed tomography imaging in patients with vertigo: population-based cohort study

Stroke 46:108-113. University of Toronto, Toronto, ON, Canada; University Health Network, Toronto, ON, Canada; Institute for Clinical Evaluative Sciences, Toronto, ON, Canada BACKGROUND AND PURPOSE: […]

The effect of pelvic fractures on future stress incontinence and pelvic organ prolapse surgery

Int Urogynecol J Western University, London, ON, Canad INTRODUCTION AND HYPOTHESIS: Pelvic fractures in women significantly disrupt the pelvic floor, which may cause stress urinary […]

Association between metformin use and mortality after cervical cancer in older women with diabetes

Cancer Epidemiol Biomarkers Prev 25:507-512. University Health Network, Toronto, ON, Canada; University of Toronto, Toronto, ON, Canada; Women’s College Hospital, Toronto, ON, Canada; Institute of […]

Effect of specialized diagnostic assessment units on the time to diagnosis in screen-detected breast cancer patients

Br J Cancer 112:1744-1750. Queen’s University, 10 Stuart Street, Kingston, ON, Canada; Cancer Care Ontario, Toronto, ON, Canada; Kingston General Hospital, Kingston, ON, Canada; University […]

Is the association between physical activity and healthcare utilization affected by self-rated health and socio-economic factors?

BMC Public Health 15:737. Lund University, Malmö, Sweden BACKGROUND: Physical activity and healthcare utilization has negative association. However, there appears to be limited knowledge of […]

Full-service family practice in British Columbia: policy interventions and trends in practice, 1991-2010

Healthc Policy 9:32-47. University of British Columbia Vancouver, BC, Canada BACKGROUND: British Columbia’s primary care reform (initiated in 2002) aims to promote “full-service family practice” […]