***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background — Heart failure has an annual mortality rate ranging from 5 % to 75 % . The purpose of the study was to develop and vali date a multivariate risk model to predict 1- , 2- , and 3-year survival in heart failure patients with the use of easily obtainable characteristics relating to clinical status , therapy ( pharmacological as well as devices ) , and laboratory parameters . Methods and Results — The Seattle Heart Failure Model was derived in a cohort of 1125 heart failure patients with the use of a multivariate Cox model . For medications and devices not available in the derivation data base , hazard ratios were estimated from published literature . The model was prospect ively vali date d in 5 additional cohorts totaling 9942 heart failure patients and 17 307 person-years of follow-up . The accuracy of the model was excellent , with predicted versus actual 1-year survival rates of 73.4 % versus 74.3 % in the derivation cohort and 90.5 % versus 88.5 % , 86.5 % versus 86.5 % , 83.8 % versus 83.3 % , 90.9 % versus 91.0 % , and 89.6 % versus 86.7 % in the 5 validation cohorts . For the lowest score , the 2-year survival was 92.8 % compared with 88.7 % , 77.8 % , 58.1 % , 29.5 % , and 10.8 % for scores of 0 , 1 , 2 , 3 , and 4 , respectively . The overall receiver operating characteristic area under the curve was 0.729 ( 95 % CI , 0.714 to 0.744 ) . The model also allowed estimation of the benefit of adding medications or devices to an individual patient 's therapeutic regimen . Conclusions — The Seattle Heart Failure Model provides an accurate estimate of 1- , 2- , and 3-year survival with the use of easily obtained clinical , pharmacological , device , and laboratory characteristics BACKGROUND AND OBJECTIVES Prognostic information is rarely conveyed by nephrologists because of clinical uncertainty about accuracy . The objective of this study was to develop an integrated prognostic model of 6-mo survival for patients who receive hemodialysis ( HD ) .  DESIGN , SETTING , PARTICIPANTS , & MEASUREMENTS A short-term prognostic model was developed using prospect i ve data from a derivation cohort of 512 patients who were receiving HD at five dialysis clinics . Patient charts were review ed for actuarial predictors ( e.g. , Charlson Comorbidity ) , and nephrologists answered the " surprise " question ( SQ ) , " Would I be surprised if this patient died within the next 6 mo ? " Survival was monitored for up to 24 mo . The prognostic model was tested with a validation cohort of 514 patients from eight clinics . RESULTS In a Cox multivariate analysis of the derivation cohort , five variables were independently associated with early mortality : Older age ( hazard ratio [ HR ] for a 10-yr increase 1.36 ; 95 % confidence interval [ CI ] 1.17 to 1.57 ) , dementia ( HR 2.24 ; 95 % CI 1.11 to 4.48 ) , peripheral vascular disease ( HR 1.88 ; 95 % CI 1.24 to 2.84 ) , decreased albumin ( HR for a 1-U increase 0.27 ; 95 % CI 0.15 to 0.50 ) , and SQ ( HR 2.71 ; 95 % CI 1.76 to 4.17 ) . Area under the curve for the result ing prognostic model predictions of 6-mo mortality were 0.87 ( 95 % CI 0.82 to 0.92 ) in the derivation cohort and 0.80 ( 95 % CI 0.73 to 0.88 ) in the validation cohort . CONCLUSIONS An integrated 6-mo prognostic tool was developed and vali date d for the HD population . The instrument may be of value for research ers and clinicians to improve end-of-life care by providing more accurate prognostic information CONTEXT Patients with chronic heart failure have impaired long-term survival , but their own expectations regarding prognosis have not been well studied . OBJECTIVES To quantify expectations for survival in patients with heart failure , to compare patient expectations to model predictions , and to identify factors associated with discrepancies between patient-predicted and model-predicted prognosis . DESIGN , SETTING , AND PARTICIPANTS Prospect i ve face-to-face survey of patients from the single-center Duke Heart Failure Disease Management Program between July and December 2004 , with follow-up through February 2008 . Patient-predicted life expectancy  was obtained using a visual analog scale . Model-predicted life expectancy was calculated using the Seattle Heart Failure Model . Actuarial-predicted life expectancy , based on age and sex alone , was calculated using life tables . Observed survival was determined from review of medical records and search of the Social Security Death Index . MAIN OUTCOME MEASURE Life expectancy ratio ( LER ) , defined as the ratio of patient-predicted to model-predicted life expectancy . RESULTS The cohort consisted of 122 patients ( mean age , 62 years ; 47 % African American , 42 % New York Heart Association [ NYHA ] class III or IV ) . On average , patients overestimated their life expectancy relative to model-predicted life expectancy ( median patient-predicted life expectancy , 13.0 years ; model-predicted expectancy , 10.0 years ) . Median LER was 1.4 ( interquartile range , 0.8 - 2.5 ) . Younger age , increased NYHA class , lower ejection fraction , and less depression were the most significant predictors of higher LER . During a median follow-up of 3.1 years , 29 % of the original cohort died . There was no association between higher LER and improved survival ( adjusted hazard ratio for overestimated compared with concordant LER , 1.05 ; 95 % confidence interval , 0.46 - 2.42 ) . CONCLUSIONS Ambulatory patients with heart failure tended to substantially overestimate their life expectancy compared with model-based predictions for survival . Because differences in perceived survival could affect decision making regarding advanced therapies and end-of-life planning , the causes of these discordant predictions warrant further study Abstract Objective : To describe doctors ' prognostic accuracy in terminally ill patients and to evaluate the determinants of that accuracy . Design : Prospect i ve cohort study Setting : Five outpatient hospice programmes in Chicago Participants : 343 doctors provided survival estimates for 468 terminally ill patients at the time of hospice referral Main outcome measures : Patients ' estimated and actual survival . Results : Median survival was 24 days . Only 20 % ( 92/468 ) of predictions were accurate ( within 33 % of actual survival ) ; 63 % ( 295/468 ) were overoptimistic and 17 % ( 81/468 ) were overpessimistic . Overall , doctors overestimated survival by a factor of 5.3 . Few patient or doctor characteristics were associated with prognostic accuracy . Male patients were 58 % less likely to have overpessimistic predictions . Non-oncology medical specialists were 326 % more likely than general internists to make overpessimistic predictions . Doctors in the upper quartile of practice experience were the most accurate . As duration of doctor-patient relationship increased and time since last contact decreased , prognostic accuracy decreased . Conclusion : Doctors are inaccurate in their prognoses for terminally ill patients and the error is systematic ally optimistic . The inaccuracy is , in general , not restricted to certain kinds of doctors or patients . These phenomena may be adversely affecting the quality of care given to patients near the end of In order to describe the outcomes of patients hospitalized with an acute exacerbation of severe chronic obstructive pulmonary disease ( COPD ) and determine the relationship between patient characteristics and length of survival , we studied a prospect i ve cohort of 1,016 adult patients from five hospitals who were admitted with an exacerbation of COPD and a PaCO2 of 50 mm Hg or more . Patient characteristics and acute physiology were determined . Outcomes were evaluated over a 6 mo period . Although only 11 % of the patients died during the index hospital stay , the 60-d , 180-d , 1-yr , and 2-yr mortality was high ( 20 % , 33 % , 43 % , and 49 % , respectively ) . The median cost of the index hospital stay was $ 7,100 ( $ 4,100 to $ 16,000 ; interquartile range ) . The median length of the index hospital stay was 9 d ( 5 to 15 d ) . After discharge , 446 patients were readmitted 754 times in the next 6 mo . At 6 mo , only 26 % of the cohort were both alive and able to report a good , very good , or excellent quality of life . Survival time was independently related to severity of illness , body mass index ( BMI ) , age , prior functional status , PaO2/FI(O2 ) , congestive heart failure , serum albumin , and the presence of cor pulmonale . Patients and caregivers should be aware of the likelihood of poor outcomes following hospitalization for exacerbation of COPD associated with hypercarbia CONTEXT The long-term results of r and omized trials have demonstrated equivalent survival rates for mastectomy and breast-conserving therapy for the treatment of early stage breast cancer . Consequently , the choice of treatment should be based on a patient 's preferences . OBJECTIVE To evaluate the impact of a decision aid regarding the different surgical treatment options on patient decision making . DESIGN AND SETTING A cluster r and omized trial for which general surgeons in the communities of central -west , and eastern Ontario , Canada , were r and omly assigned to use the decision aid or not in the surgical consultation . Patients received the decision aid or not based on the surgeon seen . PARTICIPANTS Twenty surgeons participated in the study . Of the 208 eligible women with newly diagnosed clinical stage I or II breast cancer seen by study surgeons , 201 agreed to be evaluated : 94 were assigned to the decision board and 107 to usual practice . Patients were recruited from November 1999 to April 2002 . INTERVENTION The decision board is a decision aid design ed to help physicians inform their patients about different treatment options and to enable patients to express a preference for treatment . MAIN OUTCOME MEASURES Patient knowledge about the surgical treatment of breast cancer ; decisional conflict ; satisfaction with decision making ; and the treatment decision following the consultation . RESULTS Patients in the decision board group had higher knowledge scores about their treatment options ( 66.9 vs 58.7 ; P<.001 ) , had less decisional conflict ( 1.40 vs 1.62 , P = .02 ) , and were more satisfied with decision making ( 4.50 vs 4.32 , P = .05 ) following the consultation . Patients who used the decision board were more likely to choose BCT ( 94 % vs 76 % , P = .03 ) . CONCLUSIONS The decision board was helpful in improving communication and enabling women to make a choice regarding treatment . Such instruments should be considered by surgeons when communicating the different surgical options to women with breast cancer Background : Provision of palliative care for patients with non-cancer conditions is hindered by the difficulty of predicting when people will die and fear of causing distress by raising end-of-life issues . Objectives : To compare patients ’ and professionals ’ ( 1 ) estimations of prognosis ; ( 2 ) perceptions of the seriousness of the illness and needs for supportive care ; and ( 3 ) acceptability of this sensitive research , in end-stage cancer and non-cancer diseases . Design : Prospect i ve cohort study . Setting : A teaching hospital and a Marie Curie hospice in London . Subjects : Twenty patients with advanced non-malignant disease ( heart failure , chronic obstructive pulmonary disease and renal failure ) and 20 patients with advanced cancer , and their physicians in charge . Method : A feasibility study using vignettes to aid patients and doctors estimate of prognoses . Main outcome measures were ( 1 ) patients ’ and physicians ’ estimates of health status , care needs and prognosis ; and ( 2 ) patient survival . Results : Patients were willing and able to estimate their own life expectancy and cancer patients correctly estimated that they had a poorer prognosis than non-cancer patients . Non-cancer patients perceived that they had similar needs for supportive care as cancer patients . Physicians made little distinction in palliative care needs between patients with and without cancer , but tended to make more pessimistic estimates of prognosis in non-cancer patients . Conclusions : Patients are able to judge their health status and life expectancy and do not object to questions about end-of-life care . Cancer and non-cancer patients have similar needs for supportive care . We need further evidence on the value of self-rated prognosis and how to provide palliative and supportive care for all patients who are near death Underst and ing patients ' preferences for end-of-life care and their desire to communicate with their physicians about end-of-life care decisions is of increasing interest . Recent studies [ 1 - 4 ] demonstrated that although a majority of surveyed patients ( both inpatient and ambulatory ) want to discuss cardiopulmonary resuscitation and other end-of-life decisions with their physicians , less than 50 % of patients have actually done so . Physicians and patients ' family members are frequently unaware of patient preferences for end-of-life care ; this suggests that communication about these issues may be inadequate . Several studies have shown that concordance between substituted jud 
    Output:
    
life-limiting disease .
The available evidence showed that patients with heart and renal failure can make unrealistically optimistic predictions .