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Dive into the research topics where Greg Samsa is active.

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Featured researches published by Greg Samsa.


Medical Decision Making | 2001

General Performance on a Numeracy Scale among Highly Educated Samples

Isaac M. Lipkus; Greg Samsa; Barbara K. Rimer

Background. Numeracy, how facile people are with basic probability and mathematical concepts, is associated with how people perceive health risks. Performance on simple numeracy problems has been poor among populations with little as well as more formal education. Here, we examine how highly educated participants performed on a general and an expanded numeracy scale. The latter was designed within the context of health risks. Method. A total of 463 men and women aged 40 and older completed a 3-item general and an expanded 7-item numeracy scale. The expanded scale assessed how well people 1) differentiate and perform simple mathematical operations on risk magnitudes using percentages and proportions, 2) convert percentages to proportions, 3) convert proportions to percentages, and 4) convert probabilities to proportions. Results. On average, 18% and 32% of participants correctly answered all of the general and expanded numeracy scale items. Approximately 16% to 20% incorrectly answered the most straightforward questions pertaining to risk magnitudes (e.g., Which represents the larger risk: 1%, 5%, or 10%?). A factor analysis revealed that the general and expanded risk numeracy items tapped the construct of global numeracy. Conclusions. These results suggest that even highly educated participants have difficulty with relatively simple numeracy questions, thus replicating in part earlier studies. The implication is that usual strategies for communicating numerical risk may be flawed. Methods and consequences of communicating health risk information tailored to a person’s level of numeracy should be explored further.


PharmacoEconomics | 1999

Determining clinically important differences in health status measures: a general approach with illustration to the Health Utilities Index Mark II.

Greg Samsa; David Edelman; Margaret L. Rothman; G. Rhys Williams; Joseph Lipscomb; David B. Matchar

The objective of this article was to describe and illustrate a comprehensive approach for estimating clinically important differences (CIDs) in health-related quality-of-life (HR-QOL). A literature review and pilot study were conducted to determine whether effect size-based benchmarks are consistent with CIDs obtained from other approaches.CIDs may be estimated based primarily upon effect sizes, supplemented by more traditional anchor-based methods of benchmarking (i.e. direct, cross-sectional or longitudinal approaches). A literature review of articles discussing CIDs provided comparative data on effect sizes for various chronic conditions. A pilot study was then conducted to estimate the minimum CID of the Health Utilities Index (HUI) Mark II, and to compare the observed between-group differences observed in a recent randomised trial of an acute stroke intervention with this benchmark.The use of standardised effect size benchmarks has a number of advantages–for example, effect sizes are efficient, widely accepted outside HR-QOL, and have well accepted benchmarks based upon external anchors. In addition, our literature review and pilot study suggest that effect size-based CID benchmarks are similar to those which would be obtained using more traditional methods. For most HR-QOL instruments, we do not know the changes in score which constitute CIDs of various magnitudes. This makes interpretation of HR-QOL results from clinical trials difficult, and having a benchmarking process which is relatively straightforward would be highly desirable.


Journal of the American Geriatrics Society | 1994

Predicting falls: the role of mobility and nonphysical factors.

Stephanie A. Studenski; Pamela W. Duncan; Julie Chandler; Greg Samsa; Barbara Prescott; Carol J. Hogue; Lucille B. Bearon

Our purpose was to test a four‐domain predictive model of recurrent falls developed for this study. In this model, limited mobility is considered a necessary but not sufficient element in risk of recurrent falls. Three other domains, attitudinal, social, and environmental, are proposed to influence fall risk only in persons with impaired mobility.


Journal of the American Geriatrics Society | 1996

The Relative Importance of Strength and Balance in Chair Rise by Functionally Impaired Older Individuals

Margaret Schenkman; Michael A. Hughes; Greg Samsa; Stephanie Studenski

OBJECTIVE: The ability to stand independently and safely from the seated position is essential for independent function. This investigation determined the relative contributions of measures of lower extremity strength and measures of balance control in explaining the performance characteristics of sitting‐to‐standing. Variables analyzed included those related to success of the activity (e.g., time to rise, lowest chair height) and to biomechanical characteristics of performance (e.g., how fast specific body segments moved).


JAMA Internal Medicine | 2015

Safety and benefit of discontinuing statin therapy in the setting of advanced, life-limiting illness: a randomized clinical trial.

Jean S. Kutner; Patrick J. Blatchford; Donald H. Taylor; Christine S. Ritchie; Janet Bull; Diane L. Fairclough; Laura C. Hanson; Thomas W. LeBlanc; Greg Samsa; Steven Wolf; Noreen M. Aziz; Betty Ferrell; Nina D. Wagner-Johnston; S. Yousuf Zafar; James F. Cleary; Sandesh Dev; Patricia S. Goode; Arif H. Kamal; Cordt T. Kassner; Elizabeth Kvale; Janelle G. McCallum; Adeboye Ogunseitan; Steven Z. Pantilat; Russell K. Portenoy; Maryjo Prince-Paul; Jeff A. Sloan; Keith M. Swetz; Charles F. von Gunten; Amy P. Abernethy

IMPORTANCE For patients with limited prognosis, some medication risks may outweigh the benefits, particularly when benefits take years to accrue; statins are one example. Data are lacking regarding the risks and benefits of discontinuing statin therapy for patients with limited life expectancy. OBJECTIVE To evaluate the safety, clinical, and cost impact of discontinuing statin medications for patients in the palliative care setting. DESIGN, SETTING, AND PARTICIPANTS This was a multicenter, parallel-group, unblinded, pragmatic clinical trial. Eligibility included adults with an estimated life expectancy of between 1 month and 1 year, statin therapy for 3 months or more for primary or secondary prevention of cardiovascular disease, recent deterioration in functional status, and no recent active cardiovascular disease. Participants were randomized to either discontinue or continue statin therapy and were monitored monthly for up to 1 year. The study was conducted from June 3, 2011, to May 2, 2013. All analyses were performed using an intent-to-treat approach. INTERVENTIONS Statin therapy was withdrawn from eligible patients who were randomized to the discontinuation group. Patients in the continuation group continued to receive statins. MAIN OUTCOMES AND MEASURES Outcomes included death within 60 days (primary outcome), survival, cardiovascular events, performance status, quality of life (QOL), symptoms, number of nonstatin medications, and cost savings. RESULTS A total of 381 patients were enrolled; 189 of these were randomized to discontinue statins, and 192 were randomized to continue therapy. Mean (SD) age was 74.1 (11.6) years, 22.0% of the participants were cognitively impaired, and 48.8% had cancer. The proportion of participants in the discontinuation vs continuation groups who died within 60 days was not significantly different (23.8% vs 20.3%; 90% CI, -3.5% to 10.5%; P=.36) and did not meet the noninferiority end point. Total QOL was better for the group discontinuing statin therapy (mean McGill QOL score, 7.11 vs 6.85; P=.04). Few participants experienced cardiovascular events (13 in the discontinuation group vs 11 in the continuation group). Mean cost savings were


Hypertension | 2009

Hypertension Improvement Project. Randomized Trial of Quality Improvement for Physicians and Lifestyle Modification for Patients

Laura P. Svetkey; Kathryn I. Pollak; William S. Yancy; Rowena J Dolor; Bryan C. Batch; Greg Samsa; David B. Matchar; Pao-Hwa Lin

3.37 per day and


Health and Quality of Life Outcomes | 2004

A new instrument for measuring anticoagulation-related quality of life: development and preliminary validation.

Greg Samsa; David B. Matchar; Rowena J Dolor; Ingela Wiklund; Ewa Hedner; Gail Wygant; Ole Hauch; Cheryl Beadle Marple; Roger Edwards

716 per patient. CONCLUSIONS AND RELEVANCE This pragmatic trial suggests that stopping statin medication therapy is safe and may be associated with benefits including improved QOL, use of fewer nonstatin medications, and a corresponding reduction in medication costs. Thoughtful patient-provider discussions regarding the uncertain benefit and potential decrement in QOL associated with statin continuation in this setting are warranted. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01415934.


Journal of the American Geriatrics Society | 1992

Predictors of Two-Year Post-Hospitalization Mortality among Elderly Veterans in a Study Evaluating a Geriatric Consultation Team

Harvey J. Cohen; Constance C. Saltz; Greg Samsa; Laura J. McVey; Donald E. Davis; John R. Feussner

Despite widely publicized hypertension treatment guidelines for physicians and lifestyle recommendations for patients, blood pressure control rates remain low. In community-based primary care clinics, we performed a nested, 2×2 randomized, controlled trial of physician intervention versus control and/or patient intervention versus control. Physician intervention included internet-based training, self-monitoring, and quarterly feedback reports. Patient intervention included 20 weekly group sessions followed by 12 monthly telephone counseling contacts and focused on weight loss, Dietary Approaches to Stop Hypertension dietary pattern, exercise, and reduced sodium intake. The primary outcome was change in systolic blood pressure at 6 months. Eight primary care practices (32 physicians) were randomized to physician intervention or control groups. Within those practices, 574 patients were randomized to patient intervention or control groups. Patient mean age was 60 years, 61% were women, and 37% were black. Blood pressure data were available for 91% of patients at 6 months. The main effect of physician intervention on systolic blood pressure at 6 months, adjusted for baseline pressure, was 0.3 mm Hg (95% CI: −1.5 to 2.2; P=0.72). The main effect of the patient intervention was −2.6 mm Hg (95% CI: −4.4 to −0.7; P=0.01). The interaction of the 2 interventions was significant (P=0.03); the largest impact was observed with the combination of physician and patient intervention (−9.7±12.7 mm Hg). Differences between treatment groups did not persist at 18 months. Combined physician and patient interventions lowers blood pressure; future research should focus on enhancing effectiveness and sustainability of these interventions.


Medical Decision Making | 1997

Assessing uncertainty in cost-effectiveness analyses: application to a complex decision model.

Giovanni Parmigiani; Greg Samsa; Marek Ancukiewicz; Joseph Lipscomb; Vic Hasselblad; David B. Matchar

BackgroundAnticoagulation can reduce quality of life, and different models of anticoagulation management might have different impacts on satisfaction with this component of medical care. Yet, to our knowledge, there are no scales measuring quality of life and satisfaction with anticoagulation that can be generalized across different models of anticoagulation management. We describe the development and preliminary validation of such an instrument – the Duke Anticoagulation Satisfaction Scale (DASS).MethodsThe DASS is a 25-item scale addressing the (a) negative impacts of anticoagulation (limitations, hassles and burdens); and (b) positive impacts of anticoagulation (confidence, reassurance, satisfaction). Each item has 7 possible responses. The DASS was administered to 262 patients currently receiving oral anticoagulation. Scales measuring generic quality of life, satisfaction with medical care, and tendency to provide socially desirable responses were also administered. Statistical analysis included assessment of item variability, internal consistency (Cronbachs alpha), scale structure (factor analysis), and correlations between the DASS and demographic variables, clinical characteristics, and scores on the above scales. A follow-up study of 105 additional patients assessed test-retest reliability.Results220 subjects answered all items. Ceiling and floor effects were modest, and 25 of the 27 proposed items grouped into 2 factors (positive impacts, negative impacts, this latter factor being potentially subdivided into limitations versus hassles and burdens). Each factor had a high degree of internal consistency (Cronbachs alpha 0.78–0.91). The limitations and hassles factors consistently correlated with the SF-36 scales measuring generic quality of life, while the positive psychological impact scale correlated with age and time on anticoagulation. The intra-class correlation coefficient for test-retest reliability was 0.80.ConclusionsThe DASS has demonstrated reasonable psychometric properties to date. Further validation is ongoing. To the degree that dissatisfaction with anticoagulation leads to decreased adherence, poorer INR control, and poor clinical outcomes, the DASS has the potential to help identify reasons for dissatisfaction (and positive satisfaction), and thus help to develop interventions to break this cycle. As an instrument designed to be applicable across multiple models of anticoagulation management, the DASS could be crucial in the scientific comparison between those models of care.


Journal of General Internal Medicine | 1991

Predicting the outcomes of electrophysiologic studies of patients with unexplained syncope - Preliminary validation of a derived model

Mark Linzer; Eric N. Prystowsky; George W. Divine; David B. Matchar; Greg Samsa; Frank E. Harrell; Joyce C. Pressley; David B. Pryor

Objective: To determine predictors of 2‐year post‐hospitalization mortality in a cohort of elderly hospitalized patients originally assembled to assess the impact of a Geriatric Consultation Team (GCT).

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David B. Matchar

National University of Singapore

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