***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 
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    ***EXAMPLES*** 
    Input: Background — Evidence on economically efficient strategies to lower  blood pressure ( BP )  from low- and middle-income countries remains scarce . The Control of Blood Pressure and Risk Attenuation ( COBRA ) trial r and omized 1341 hypertensive subjects in 12 r and omly selected communities in Karachi , Pakistan , to 3 intervention programs : ( 1 ) combined home health education ( HHE ) plus trained general practitioner ( GP ) ; ( 2 ) HHE only ; and ( 3 ) trained GP only . The comparator was no intervention ( or usual care ) . The reduction in BP was most pronounced in the combined group . The present study examined the cost-effectiveness of these strategies . Methods and Results — Total costs were assessed at baseline and 2 years to estimate incremental cost-effectiveness ratios based on ( 1 ) intervention cost ; ( 2 ) cost of physician consultation , medications , diagnostics , changes in lifestyle , and productivity loss ; and ( 3 ) change in systolic BP . Precision of the incremental cost-effectiveness ratio estimates was assessed by 1000 bootstrapping replications . Bayesian probabilistic sensitivity analysis was also performed . The annual costs per participant associated with the combined HHE plus trained GP , HHE alone , and trained GP alone were $ 3.99 , $ 3.34 , and $ 0.65 , respectively . HHE plus trained GP was the most cost-effective intervention , with an incremental cost-effectiveness ratio of $ 23 ( 95 confidence interval , 6–99 ) per mm Hg reduction in systolic BP compared with usual care , and remained so in 97.7 of 1000 bootstrapped replications . Conclusions — The combined intervention of HHE plus trained GP is potentially affordable and more cost-effective for BP control than usual care or either strategy alone in some communities in Pakistan , and possibly other countries in Indochina with similar healthcare infrastructure . Clinical Trial Registration — http://www . clinical trials.gov . Unique identifier : NCT00327574 OBJECTIVE To evaluate a simple cardiovascular risk management package for assessing and managing cardiovascular risk using hypertension as an entry point in primary care facilities in low-re source setting s. METHODS Two geographically distant regions in two countries ( China and Nigeria ) were selected and 10 pairs of primary care facilities in each region were r and omly selected and matched . Regions were then r and omly assigned to a control group , which received usual care , or to an intervention group , which applied the cardiovascular risk management package . Each facility enrolled 60 consecutive patients with hypertension . Intervention sites educated patients about risk factors at baseline and initiated treatment with hydrochlorothiazide at 4 months in patients at medium risk of a cardiovascular event , according to a st and ardized treatment algorithm . Systolic blood pressure change from baseline to 12 months was the primary outcome measure . FINDINGS The study included 2397 patients with baseline hypertension : 1191 in 20 intervention facilities and 1206 in 20 control facilities .  Systolic and diastolic blood pressure decreased more in intervention patients than in controls . However , at 12 months more than half of patients still had uncontrolled hypertension ( systolic blood pressure > 140 mmHg and /or diastolic blood pressure > 90 mmHg ) . Behavioural risk factors had improved among intervention patients in Nigeria but not in China . Only about 2 % of hypertensive patients required referral to the next level of care . CONCLUSION Even in low-re source setting s , hypertensive patients can be effectively assessed and managed in primary care facilities Lifestyle factors like weight , alcohol consumption , salt intake and physical activity have shown to be important in treating hypertension . There have been made some r and omised trials about the effects of lifestyle interventions , but the numbers of patients have been relatively small and the duration s of follow-ups have been short . No controlled trials assessing the effects of lifestyle intervention in a rehabilitation setting have been reported . In this study , the effects of multidisciplinary lifestyle intervention in rehabilitation centres among middle-aged hypertensive employees were described . A total of 731 hypertensives from 45 worksites were r and omised to lifestyle intervention in a rehabilitation centre or to usual care in an occupational or primary health-care centre for 12 months . St and ard measurements were conducted before the intervention and 1-year later . Blood pressure ( BP ) levels were clearly reduced in the intervention group , while only minor changes were observed in the control group . The net changes between the two groups both for systolic and diastolic BPs were −2.1 mmHg ( 95 % confidence intervals ( CI ) −4.0 to −0.1 ) and −1.5 mmHg ( 95 % CI −2.6 to −0.4 ) , respectively . The net changes were greater among men than women . The multidisciplinary lifestyle intervention in a rehabilitation centre setting produced significant reductions in BP among middle-aged employees with hypertension Background & objectives : Cardiovascular risk factors clustering associated with blood pressure ( BP ) has not been studied in the Indian population . This study was aim ed at assessing the clustering effect of cardiovascular risk factors with suboptimal BP in Indian population as also the impact of risk reduction interventions . Methods : Data from 10543 individuals collected in a nation-wide surveillance programme in India were analysed . The burden of risk factors clustering with blood pressure and coronary heart disease ( CHD ) was assessed . The impact of a risk reduction programmme on risk factors clustering was prospect ively studied in a sub-group . Results : Mean age of participants was 40.9 ± 11.0 yr . A significant linear increase in number of risk factors with increasing blood pressure , irrespective of stratifying using different risk factor thresholds was observed . While hypertension occurred in isolation in 2.6 per cent of the total population , co-existence of hypertension and > 3 risk factors was observed in 12.3 per cent population . A comprehensive risk reduction programme significantly reduced the mean number of additional risk factors in the intervention population across the blood pressure groups , while it continued to be high in the control arm without interventions ( both within group and between group P<0.001 ) . The proportion of ‘ low risk phenotype ’ increased from 13.4 to 19.9 per cent in the intervention population and it was decreased from 27.8 to 10.6 per cent in the control population ( P<0.001 ) . The proportion of individuals with hypertension and three more risk factors decreased from 10.6 to 4.7 per cent in the intervention arm while it was increased from 13.3 to 17.8 per cent in the control arm ( P<0.001 ) . Interpretation & conclusions : Our findings showed that cardiovascular risk factors clustered together with elevated blood pressure and a risk reduction programme significantly reduced the risk factors burden Background Dealing with heterogeneity in meta-analyses is often tricky , and there is only limited advice for authors on what to do . We investigated how authors addressed different degrees of heterogeneity , in particular whether they used a fixed effect model , which assumes that all the included studies are estimating the same true effect , or a r and om effects model where this is not assumed . Methods We sample d r and omly 60 Cochrane review s from 2008 , which presented a result in its first meta- analysis with substantial heterogeneity ( I2 greater than 50 % , i.e. more than 50 % of the variation is due to heterogeneity rather than chance ) . We extracted information on choice of statistical model , how the authors had h and led the heterogeneity , and assessed the method ological quality of the review s in relation to this . Results The distribution of heterogeneity was rather uniform in the whole I2 interval , 50 - 100 % . A fixed effect model was used in 33 review s ( 55 % ) , but there was no correlation between I2 and choice of model ( P = 0.79 ) . We considered that 20 review s ( 33 % ) , 16 of which had used a fixed effect model , had major problems . The most common problems were : use of a fixed effect model and lack of rationale for choice of that model , lack of comment on even severe heterogeneity and of reservations and explanations of its likely causes . The problematic review s had significantly fewer included trials than other review s ( 4.3 vs. 8.0 , P = 0.024 ) . The problems became less pronounced with time , as those review s that were most recently up date d more often used a r and om effects model . Conclusion One-third of Cochrane review s with substantial heterogeneity had major problems in relation to their h and ling of heterogeneity . More attention is needed to this issue , as the problems we identified can be essential for the conclusions of the review Context Weight loss and exercise decrease the development of diabetes in people with impaired glucose tolerance , but the effectiveness of these interventions in people with normal glucose tolerance is unknown . Contribution Using data from a large r and omized , controlled trial of cardiovascular disease prevention in men , the investigators show that participants with normal glucose tolerance at baseline developed diabetes at similar rates whether they received the diet and exercise intervention or usual care . However , the intervention was associated with lower risk of diabetes among nonsmokers . Implication s While diet and exercise may reduce the development of diabetes in nonsmokers with normal glucose metabolism at baseline , this benefit was not apparent among smokers . The Editors Epidemiologic studies have identified several potentially modifiable risk factors for type 2 diabetes mellitus , including obesity , a diet in which a high proportion of calories comes from fat , and low levels of physical activity ( 1 - 7 ) . Authorities have advocated that trials should test promising hypotheses about the primary prevention of type 2 diabetes ( 1 ) . R and omized intervention studies have demonstrated that , among those who already have impaired glucose tolerance , interventions that promote weight loss and increased exercise can reduce the risk for incident diabetes ( 8 - 10 ) . However , interventions should occur before at-risk individuals develop impaired glucose tolerance . A 2-year r and omized trial of diet , exercise , or both in individuals with a parental history of diabetes showed a statistically imprecise lower risk for developing diabetes in the intervention group ( 11 ) . To test such a hypothesis in groups who do not necessarily have a parental history of diabetes would be expensive . Strategies proposed for the primary prevention of type 2 diabetes include  weight reduction , reduced dietary fat intake , and increased exercise  ( 2 , 4 , 7 ) . These interventions are similar to those developed for preventing coronary heart disease ; therefore , examination of type 2 diabetes incidence rates in coronary heart disease prevention trials can provide preliminary evidence on the potential of such interventions to reduce type 2 diabetes risk . The Multiple Risk Factor Intervention Trial ( MRFIT ) enrolled 12866 middle-aged men at high risk for coronary heart disease and delivered either special intervention or usual care  over 6 to 7 years . The research ers obtained fasting glucose values yearly , and participants self-reported their use of insulin or oral hypoglycemic agents . The glucose values and reports of diabetes medication use enable estimation of diabetes incidence during the trial . Previous reports from MRFIT have described risk factors for the development of diabetes in the usual care group ( 12 ) and the risk for death associated with incident diabetes in the combined special intervention and usual care groups ( 13 ) . In this paper , we compare the incidence of diabetes in the  intervention and control groups of the MRFIT , report on an unexpected subgroup finding related to baseline cigarette smoking status , and explore reasons for the different results among smokers and nonsmokers . Methods Procedures Detailed descriptions of the MRFIT have been published ( 14 - 17 ) . Briefly , between 1973 and 1976 , the MRFIT investigators screened 361662 men for eligibility at 22 U.S. clinical centers . Of this group , 12866 men age 35 to 57 years were r and omly assigned : 6428 men to the special intervention group and 6438 men to the usual care group . Screening occurred at 3 visits . At the first screening visit , investigators assessed the risk for coronary heart disease by using measurements of serum cholesterol level , diastolic blood pressure , and self-reported cigarette smoking ( 14 ) . Men who were in the upper 15 % ( changed to 10 % after one third of the screening was completed ) of risk were invited to attend a second screening visit . Because of the eligibility criteria used in the MRFIT , the usual relationships among these risk factors were modified . For example , nonsmokers had to have higher blood pressure and lipid levels on average than smokers to be eligible for the trial . At the second screening visit , a blood sample was taken after an overnight fast . A central laboratory at the Institute of Medical Sciences in San Francisco , California , analyzed the blood sample s by using a protocol previously described ( 18 ) and measured serum glucose in the fasting sample and in a sample taken 1 hour after a 75-g oral glucose load . The MRFIT also measured height and weight ( after the patient had disrobed ) . Individuals with body weight 150 % or more of desirable weight were excluded from the trial ( defined as 0.9 of the average for men of the same height in the 19601962 National Health Examination Survey [ 19 ] ) . We used body mass index ( BMI ) as the measure of relative weight in our report . Men without evidence of cardiovascular or other life-threatening diseases were invited to attend a third screening visit . At this visit , eligible men who consented to the trial were r and omly assigned . All participants had annual examinations for at least 6 years . A fasting blood sample was taken at each annual examination , from which serum 
    Output:
    
Due to the limited evidence currently available , we can draw no conclusions as to the effectiveness of multiple risk factor interventions on combined CVD events and mortality .
There is some evidence that multiple risk factor interventions may lower blood pressure levels , body mass index and waist circumference in population s in LMIC setting s at high risk of hypertension and diabetes .