***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: OBJECTIVES This study was done to compare characteristics and outcomes of patients with acute myocardial infa rct ion participating in two thrombolysis trials with those of nontrial patients at study hospitals and external hospitals . BACKGROUND Preferential recruitment of lower risk patients into r and omized trials of thrombolysis has been suggested by earlier studies . However , to date there has not been a definitive population -based comparison of characteristics and outcomes for thrombolysis trial participants and non participants . METHODS Population -based data on hospital admissions and mortality from acute myocardial infa rct ion for all hospitals in Ontario from 1989 to 1992 were linked to data on trial participants in two distinct thrombolysis studies ( GUSTO I and LATE ) . Included were 1,304 patients entered into GUSTO , 12,657 non participants at GUSTO hospitals , 249 patients entered into LATE , 5,997 non participants at LATE hospitals and 12,299 patients at external hospitals . The main outcomes were differences in age , gender , comorbidity scores , coronary revascularization and survival to hospital discharge . RESULTS Patients in both GUSTO and LATE were significantly more likely to be < 70 years old ( odds ratio [ OR ] 2.8 and 3.2 , respectively ) , to be male ( OR 2.0 and 2.1 , respectively ) , to have low comorbidity scores ( OR 2.0 and 2.3 , respectively ) and , for GUSTO alone , to undergo coronary revascularization ( OR 2.4 ) . Nontrial patients were similar between trial hospitals and external hospitals . In-hospital mortality rates for GUSTO and LATE patients were lower ( 6.9 % and 6.6 % , respectively ) than for non participants at study hospitals ( 16.8 % and 19.7 % , respectively ; p<0.001 for both comparisons ) . Survival to hospital discharge remained higher among GUSTO ( OR 1.9 ) and LATE patients ( OR 2.0 ) than non participants at study hospitals even after adjustment for age , gender , revascularization and comorbidity scores . CONCLUSIONS Compared with nontrial patients , thrombolysis trial participants are younger , more often male , undergo more revascularization and have less comorbid disease . Even after adjustment for these factors , participants have a survival advantage over non participants that is larger than expected from thrombolysis alone . These findings are not attributable to inferior care or skewed population s at hospitals that did not join these major trials . Further study of these selection biases may guide future trial design and deepen our underst and ing of why thrombolytics have been underused for high risk patients in routine practice The changes in clinical practice following a r and omised controlled trial of early discharge  for inguinal hernia and varicose veins are review ed . A significant reduction in mean length of stay was recorded in the study area between 1970 ( the year before the start of the study ) and 1975 ( two complete years after the study ) . This change was not found in two adjacent health districts Background The long‐term effects of participation in trials has not been reported . A r and omized‐controlled trial ( the ONE study ) reported on the management of gastro‐oesophageal reflux disease  with esomeprazole in primary care , testing on‐dem and treatment vs. treatment courses BACKGROUND The ADEBAR study is a prospect i ve multicenter Phase III trial to examine whether high-risk breast cancer patients > or = 4 involved axillary lymph nodes ) benefit from a sequential anthracycline-docetaxel regimen compared to st and ard chemotherapy with anthracyclines . With a median recruitment of 33 patients per month at 198 actively-recruiting centers , the ADEBAR study was the best recruiting study in Germany until the end of the trial . MATERIAL S AND METHODS A st and ardized question naire was sent to all participating centers in order to determine the extent to which treatment strategies and patient care are affected by participation in the ADEBAR study . The question naire covered 5 areas of interest : previous inclusion of patients at the same tumor stage in other studies , the type of chemotherapy received by comparable patients previously outside the study , change in the intensity of medical care since participating in the ADEBAR study , the information gained through participation in the study and changes in the overall quality of medical care . RESULTS 51.0 % ( n=98 ) of the question naires were returned , from which 3 were excluded from the analysis due to being incomplete . In the year preceding the ADEBAR study , 63.2 % of participating centers had not entered their high-risk patients into a clinical trial . Before participating in the ADEBAR protocol , 44.2 % of patients with the same indication had received inadequate therapy by today 's st and ards , such as CMF , EC/CMF or 4x EC . 59.0 % of the centers noted an increase in the intensity of patient care as a result of participation in the study , independent of the care provided purely because of the study . By being part of a research network , with a regular flow of information via newsletters , study meetings and the like , 80.0 % noted an improvement in their professional knowledge in the field of breast cancer . Moreover , 31.6 % of the centers reported an improvement in the overall quality of their patient care since the start of the trial . CONCLUSION The results of the survey demonstrate that both physicians and patients benefit from participation in clinical trials as this is associated with optimized decision-making as regards therapy and patient care OBJECTIVES : To assess the variation in practice of Barrett 's esophagus ( BE ) management in comparison with accepted international guidelines before and after the introduction of a large BE r and omized controlled trial ( RCT ) with protocol s including those of tissue sampling . DESIGN : A vali date d anonymized question naire was sent to 401 senior attending gastroenterologists asking for details of their current management of BE , especially histological sampling . Of the 228 respondents , 57 individuals ( each from a different center ) were in the first group to enter the ASPirin Esomeprazole ( BE ) Chemoprevention Trial ( AspECT ) , and we assessed change in practice in these centers . RESULTS : Ninety percent of specialists did not take adequate biopsies for histological diagnosis . Furthermore , 74 % would consider aggressive surgical resection for prevalent cases of high- grade dysplasia in BE as their first-line choice despite the associated perioperative mortality . Ninety-two percent cl aim their lack of adherence to guidelines is because there is a need for stronger evidence for surveillance and medical interventions .Effect of the AspECT trial : Those clinicians in centers where the AspECT trial has started have improved adherence to ACG guidelines compared with their previous practice ( P < 0.05 ) . BE patients now get 18.8 % more biopsies compared with previous practice , and 37.7 % if the patient is entered into the AspECT trial ( P < 0.01 ) . CONCLUSIONS : This large study indicates both wide variation in practice and poor compliance with guidelines . Because optimal histology is arguably the most important facet of BE management , the improvement in practice in centers taking part in the AspECT trial indicates an additional value of large international RCTs CONTEXT Use of experimental therapies during but outside of r and omized controlled trials ( RCTs ) has not been studied . OBJECTIVE To determine whether initiation of an RCT leads to increased use of the experimental therapy outside the trial . DESIGN AND SETTING Data on national apheresis use during 3 Canadian RCTs for multiple sclerosis ( 1986 - 1988 ) , thrombotic thrombocytopenic purpura ( 1982 - 1988 ) , and myeloma cast nephropathy ( 1998 - 2000 ) were obtained from 19 major medical centers in Canada . The multiple sclerosis and myeloma cast nephropathy trials had data on apheresis use for 3 years prior to and during the trials , which permitted a time-series analysis to determine the impact of the RCTs on the use of apheresis . The ongoing myeloma cast nephropathy trial provided data on the number of patients inside and outside of the RCTs in trial and nontrial centers . Initial and follow-up question naires were sent to 24 Canadian physicians in trial and nontrial centers to determine if they had noted an increase in  apheresis activity during the trials and , if so , their explanation for it . MAIN OUTCOME MEASURE Change in number of patients undergoing apheresis  for thrombotic thrombocytopenic purpura , multiple sclerosis , and myeloma cast nephropathy prior to and during the respective RCTs compared with all patients undergoing apheresis  during the same periods . RESULTS During all 3 RCTs , there were large increases in use of apheresis .  The majority of the increased use of apheresis  was outside of the trials : for multiple sclerosis , 30 of 49 patients per year ( 61 % of increase ) ; thrombotic thrombocytopenic purpura , 49 of 56 patients per year ( 72 % of increase ) ; and myeloma cast nephropathy , 60 of 72 patients per year ( 57 % of increase ) . The myeloma cast nephropathy study noted that this increase occurred in both nontrial and trial centers . Among question naire respondents ( n = 22 ; 92 % response rate ) , most physicians noted an increase in apheresis activity during the trials and attributed it to a " jumping-the-gun " phenomenon . CONCLUSIONS During 3 Canadian RCTs , apheresis increased , but most of the increase occurred outside the trials . This behavior during an RCT , in the absence of clear efficacy , can be termed jumping the gun The purpose of this study was to determine the effect of participation in research on staff nurses '  attitude towards , access to , perceived support of and reported use of research in practice . Six medical surgical units in a southeastern Ontario teaching hospital were r and omly assigned to receive 3 different levels of exposure to research : high , low and usual . On the high participation units , a clinical research group consisting of the investigator and interested nurses ( n = 18 ) critiqued research literature related to an important clinical issue ( i.e. , patterns of sleep ) and design ed and implemented a clinical research study . On the low participation units , a similar clinical research group ( n = 10 ) met once and were involved , solely , in the design and implementation of the clinical research protocol . On the control units , there were no formalized research groups or activities . All registered nurses ( n = 235 ) , including the research group participants , on the 6 units were surveyed with a research utilization question naire ( RUQ ) pre and post participant intervention . The RUQ scores were higher on the high participation units at baseline and post intervention in comparison to the low and control units . Nurses who participated directly in the clinical research groups ( high and low ) reported similar RUQ scores post intervention and higher scores in comparison to all nurses . All RUQ scores were higher post intervention . Nurses with clinical expertise but minimal research expertise participated meaningfully in clinical research . While participation had an individual effect there was no unit effect , suggesting other factors , such as organizational support and culture , are important determinants of research use 
    Output:
    
A Canadian study among nurses found that use of research evidence was higher for those who took part in research working groups and a Danish study on general practitioners found that trial doctors were more likely to prescribe in accordance with research evidence and guidelines .
A study of North American patients at hospitals that had taken part in trials for myocardial infa rct ion found no statistically significant difference in treatment for patients in trial and non-trial hospitals .
A Canadian study of myocardial infa rct ion patients found that trial participants had better survival than patients in the same hospitals who were not in trials or those in non-trial hospitals .
A study of general practice s in Denmark did not detect differences in guideline adherence between trial and non-trial practice s but found that trial practice s were more likely to prescribe the trial sponsor 's drugs .
Conclusions The available findings from existing research suggest that there might be a ' trial effect ' of better outcomes , greater adherence to guidelines and more use of evidence by practitioners and institutions that take part in trials .
However , the consequences for patient health are uncertain and the most robust conclusion may be that there is no apparent evidence that patients treated by practitioners or in institutions that take part in trials do worse than those treated elsewhere