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1.
Evolution ; 68(3): 802-15, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24171712

ABSTRACT

Understanding the evolutionary dynamics of inbreeding and inbreeding depression requires unbiased estimation of inbreeding depression across diverse mating systems. However, studies estimating inbreeding depression often measure inbreeding with error, for example, based on pedigree data derived from observed parental behavior that ignore paternity error stemming from multiple mating. Such paternity error causes error in estimated coefficients of inbreeding (f) and reproductive success and could bias estimates of inbreeding depression. We used complete "apparent" pedigree data compiled from observed parental behavior and analogous "actual" pedigree data comprising genetic parentage to quantify effects of paternity error stemming from extra-pair reproduction on estimates of f, reproductive success, and inbreeding depression in free-living song sparrows (Melospiza melodia). Paternity error caused widespread error in estimates of f and male reproductive success, causing inbreeding depression in male and female annual and lifetime reproductive success and juvenile male survival to be substantially underestimated. Conversely, inbreeding depression in adult male survival tended to be overestimated when paternity error was ignored. Pedigree error stemming from extra-pair reproduction therefore caused substantial and divergent bias in estimates of inbreeding depression that could bias tests of evolutionary theories regarding inbreeding and inbreeding depression and their links to variation in mating system.


Subject(s)
Genetic Fitness , Genetics, Population/methods , Inbreeding , Pedigree , Sparrows/genetics , Animals , Female , Male , Models, Genetic , Reproduction/genetics , Selection Bias , Sparrows/physiology
3.
Health Aff (Millwood) ; 32(2): 285-93, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23381521

ABSTRACT

Shared decision making is an approach to care that seeks to fully inform patients about the risks and benefits of available treatments and engage them as participants in decisions about the treatments. Although recent federal and state policies pursue the expanded use of shared decision making as a way to improve care quality and patient experience, payers and providers want evidence that this emerging model of care is cost-effective. We examined data obtained from a year-long randomized investigation. The study compared the effects on patients of receiving a usual level of support in making a medical treatment decision with the effects of receiving enhanced support, which included more contact with trained health coaches through telephone, mail, e-mail, and the Internet. We found that patients who received enhanced support had 5.3 percent lower overall medical costs than patients who received the usual level of support. The enhanced-support group had 12.5 percent fewer hospital admissions than the usual-support group, and 9.9 percent fewer preference-sensitive surgeries, including 20.9 percent fewer preference-sensitive heart surgeries. These findings indicate that support for shared decision making can generate savings. They also suggest that a "remote" model of support-combining telephonic coaching with decision aids, for example-may constitute a relatively low-cost and effective intervention that could reach broader populations without the need for the direct involvement of regular medical care team members.


Subject(s)
Decision Making , Health Care Costs , Patient Participation/methods , Cost Control/methods , Cost Control/organization & administration , Delivery of Health Care/economics , Delivery of Health Care/methods , Female , Humans , Male , Middle Aged , Patient Participation/economics , Patient Preference/economics , Quality of Health Care/economics , Quality of Health Care/organization & administration
4.
N Engl J Med ; 363(13): 1245-55, 2010 Sep 23.
Article in English | MEDLINE | ID: mdl-20860506

ABSTRACT

BACKGROUND: Studies have shown that telephone interventions designed to promote patients' self-management skills and improve patient-physician communication can increase patients' satisfaction and their use of preventive services. The effect of such a strategy on health care costs remains controversial. METHODS: We conducted a stratified, randomized study of 174,120 subjects to assess the effect of a telephone-based care-management strategy on medical costs and resource utilization. Health coaches contacted subjects with selected medical conditions and predicted high health care costs to instruct them about shared decision making, self-care, and behavioral change. The subjects were randomly assigned to either a usual-support group or an enhanced-support group. Although the same telephone intervention was delivered to the two groups, a greater number of subjects in the enhanced-support group were made eligible for coaching through the lowering of cutoff points for predicted future costs and expansion of the number of qualifying health conditions. Primary outcome measures at 1 year were total medical costs and number of hospital admissions. RESULTS: At baseline, medical costs and resource utilization were similar in the two groups. After 12 months, 10.4% of the enhanced-support group and 3.7% of the usual-support group received the telephone intervention. The average monthly medical and pharmacy costs per person in the enhanced-support group were 3.6% ($7.96) lower than those in the usual-support group ($213.82 vs. $221.78, P=0.05); a 10.1% reduction in annual hospital admissions (P<0.001) accounted for the majority of savings. The cost of this intervention program was less than $2.00 per person per month. CONCLUSIONS: A targeted telephone care-management program was successful in reducing medical costs and hospitalizations in this population-based study. (Funded by Health Dialog Services; ClinicalTrials.gov number, NCT00793260.)


Subject(s)
Health Care Costs/statistics & numerical data , Health Resources/statistics & numerical data , Patient Care Management/methods , Telemedicine , Adolescent , Adult , Aged , Child , Child, Preschool , Cost-Benefit Analysis , Emergency Service, Hospital/statistics & numerical data , Health Resources/economics , Hospitalization/statistics & numerical data , Humans , Infant , Middle Aged , Models, Theoretical , Patient Care Management/economics , Physician-Patient Relations , Telephone , Young Adult
5.
Emerg Med Clin North Am ; 27(3): 381-99, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19646643

ABSTRACT

The most common complaints among patients with cancer who present to the emergency department are related to the gastrointestinal system, and 40% of these patients complain of abdominal pain. These presentations can stem from the underlying malignancy itself, treatment directed toward the disease, or the full range of pathologies present in a healthy population. Immunosuppression may blunt many of the findings one expects in a healthy population of patients, thus rendering the clinical exam less reliable in many patients with cancer. Moreover, the degree of immunosuppression shapes both the types of pathologies the clinician should consider and the rate at which the disease may progress. Understanding the limitations of physical examination, pathophysiology of disease, and the methods by which these diagnoses are established is of critical importance in this population. This article focuses specifically on patients with cancer who present with an acute abdomen, and it discusses how a concurrent malignancy can shape the differential diagnosis in these cases.


Subject(s)
Abdomen, Acute/diagnosis , Abdomen, Acute/etiology , Neoplasms/complications , Abdomen, Acute/therapy , Ascites/diagnosis , Ascites/etiology , Ascites/therapy , Budd-Chiari Syndrome/diagnosis , Budd-Chiari Syndrome/etiology , Budd-Chiari Syndrome/therapy , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/etiology , Gastrointestinal Diseases/therapy , Humans , Immunocompromised Host , Radiotherapy/adverse effects
6.
Prehosp Disaster Med ; 23(3): 282-4, 2008.
Article in English | MEDLINE | ID: mdl-18702276

ABSTRACT

BBACKGROUND The 14 neighborhoods surrounding University of Chicago Hospitals (UCH) have both Chicago's highest "ambulatory-care-sensitive condition" hospitalization rates and lack of community-based care. To address these problems, in 2004, the Southside Medical Homes (SMH) Network began linking emergency department (ED) patients with 18 community providers. The ED-based patient navigator (patient advocate) is an integral component of this network, and both their current and developing roles will be discussed. MMETHODS Six navigators worked in the UCH-ED approached eligible patients that are flagged by the ED electronic tracking system. Patients were offered the services provided by primary-care referral and appropriate dental, mental health, and substance abuse facilities. Appointments were scheduled, and pertinent ED medical data was faxed to the outlying sites. Navigator roles were expanding with SMH to include: (1) focus on frequent user/chronic disease populations such as sickle cell disease where advocates will expedite a multidisciplinary clinic referral; (2) navigator training to better inform patients of the specific benefits a "medical home" provides for preventive and psychosocial care; (3) and improving navigator, and secondarily, patient knowledge, of community resources: health-education sites, vocational programs, advocacy agencies, support groups, etc. RRESULTS/CONCLUSIONS Data through 01 July 2007 show a monthly average of 950 ED patients surveyed and 80% of these accepting follow-up referral services. Of those patients with ED-scheduled appointments (43%) in community clinics, network data shows patients returning to their referred providers: 39% of patients have been -> or = times. The navigator role is evolving with the expansion of SMH to include: (1) frequent-user population referrals; (2) preventive health education; and (3) utilization of community resources.


Subject(s)
Community Health Services , Cooperative Behavior , Emergency Service, Hospital , Patient-Centered Care , Primary Health Care/organization & administration , Chicago , Community Health Services/organization & administration , Emergency Service, Hospital/organization & administration , Health Care Surveys , Humans , Organizational Case Studies , Organizational Innovation
7.
Acad Emerg Med ; 14(1): 74-6, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17099188

ABSTRACT

BACKGROUND: There are many different confidence interval calculation methods, each providing different as well as in some cases inadequate interval estimates. Readers who know which method is used are better able to understand potentially significant limitations in study reports. OBJECTIVES: To quantify how often confidence interval calculation methods are disclosed by authors in four peer-reviewed North American emergency-medicine journals. METHODS: The authors independently performed searches of four journals for all studies in which comparisons were made between means, medians, proportions, odds ratios, or relative risks. Case reports, editorials, subject reviews, and letters were excluded. Using a standardized abstraction form developed on a spreadsheet, the authors evaluated each article for the reporting of confidence intervals and evaluated the description of methodology used to calculate the confidence intervals. RESULTS: A total of 212 articles met the inclusion criteria. Confidence intervals were reported in 123 articles (58%; 95% CI = 51% to 64%); of these, a description of methodology was reported in 12 (9.8%; 95% CI = 5.7% to 16%). CONCLUSIONS: Confidence interval methods of calculation are disclosed infrequently in emergency medicine literature.


Subject(s)
Confidence Intervals , Emergency Medicine , Periodicals as Topic/statistics & numerical data , Documentation , Humans
8.
Am Nat ; 165(3): 299-310, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15729661

ABSTRACT

Models of sexual selection propose that exaggerated secondary sexual ornaments indicate a male's own fitness and the fitness of his offspring. These hypotheses have rarely been thoroughly tested in free-living individuals because overall fitness, as opposed to fitness components, is difficult to measure. We used 20 years of data from song sparrows (Melospiza melodia) inhabiting Mandarte Island, British Columbia, Canada, to test whether a male's song repertoire size, a secondary sexual trait, predicted overall measures of male or offspring fitness. Males with larger song repertoires contributed more independent and recruited offspring, and independent and recruited grandoffspring, to Mandarte's population. This was because these males lived longer and reared a greater proportion of hatched chicks to independence from parental care, not because females mated to males with larger repertoires laid or hatched more eggs. Furthermore, independent offspring of males with larger repertoires were more likely to recruit and then to leave more grandoffspring than were offspring of males with small repertoires. Although we cannot distinguish whether observed fitness variation reflected genetic or environmental effects on males or their offspring, these data suggest that female song sparrows would gain immediate and intergenerational fitness benefits by pairing with males with large song repertoires.


Subject(s)
Sparrows/physiology , Vocalization, Animal/physiology , Animals , British Columbia , Clutch Size , Cues , Female , Longevity , Male , Reproduction , Sex Factors , Sexual Behavior, Animal
9.
Evolution ; 56(1): 131-42, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11913658

ABSTRACT

We studied heterosis and outbreeding depression among immigrants and their descendants in a population of song sparrows on Mandarte Island, Canada. Using data spanning 19 generations, we compared survival, seasonal reproductive success, and lifetime reproductive success of immigrants, natives (birds with resident-hatched parents and grandparents), and their offspring (F1s, birds with an immigrant and a native parent, and F2s, birds with an immigrant grandparent and resident-hatched grandparent in each of their maternal and paternal lines). Lifetime reproductive success of immigrants was no worse than that of natives, but other measures of performance differed in several ways. Immigrant females laid later and showed a tendency to lay fewer clutches, but had relatively high success raising offspring per egg produced. The few immigrant males survived well but were less likely to breed than native males of the same age that were alive in the same year. Female F1s laid earlier than expected based on the average for immigrant and native females, and adult male F1s were more likely to breed than expected based on the average for immigrant and native males. The performance differences between immigrant and native females and between F1s and the average of immigrants and natives are consistent with the hypothesis that immigrants were disadvantaged by a lack of site experience and that immigrant offspring benefited from heterosis. However, we could not exclude the possibility that immigrants had a different strategy for optimizing reproductive success or that they experienced ecological compensation for life-history parameters. For example, the offspring of immigrants may have survived well because immigrants laid later and produced fewer clutches, thereby raising offspring during a period of milder climatic conditions. Although sample sizes were small, we found large performance differences between F1s and F2s, which suggested that either heterosis was associated with epistasis in F1s, that F2s experienced outbreeding depression, or that both phenomena occurred. These findings indicate that the performance of dispersers may be affected more by fine-scale genetic differentiation than previously assumed in this and comparable systems.


Subject(s)
Reproduction , Songbirds/genetics , Animals , Female , Male , Songbirds/physiology
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