***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 The work setting provides an opportunity to introduce overweight ( i.e. , Body Mass Index ≥ 25 kg/m2 ) adults to a weight management programme , but new approaches are needed in this setting . The main purpose of this study was to investigate the effectiveness of lifestyle counselling by phone or e-mail on body weight , in an overweight working population . Secondary purpose s were to establish effects on waist circumference and lifestyle behaviours , and to assess which communication method is the most effective . Methods A r and omized controlled trial with three treatments : intervention material s with phone counselling ( phone group ) ; a web-based intervention with e-mail counselling ( internet group ) ; and usual care , i.e. lifestyle brochures ( control group ) . The interventions used lifestyle modification and lasted a maximum of six months . Subjects were 1386 employees , recruited from seven companies ( 67 % male ; mean age 43 ( SD 8.6 ) y ; mean BMI 29.6 ( SD 3.5 ) kg/m2 ) .  Body weight was measured by research personnel and by question naire . Secondary outcomes fat , fruit and vegetable intake , physical activity and waist circumference were assessed by question naire . Measurements were done at baseline and after six months . Missing body weight was multiply imputed . Results Body weight reduced 1.5 kg ( 95 % CI -2.2;-0.8 , p < 0.001 ) in the phone group and 0.6 kg ( 95 % CI -1.3 ; -0.01 , p = 0.045 ) in the internet group , compared with controls . In completers analyses , weight and waist circumference in the phone group were reduced with 1.6 kg ( 95 % CI -2.2;-1.0 , p < 0.001 ) and 1.9 cm ( 95 % CI -2.7;-1.0 , p < 0.001 ) respectively , fat intake decreased with 1 fatpoint ( 1 to 4 grams)/day ( 95 % CI -1.7;-0.2 , p = 0.01 ) and physical activity increased with 866 METminutes/week ( 95 % CI 203;1530 , p = 0.01 ) , compared with controls . The internet intervention result ed in a weight loss of 1.1 kg ( 95 % CI -1.7;-0.5 , p < 0.001 ) and a reduction in waist circumference of 1.2 cm ( 95 % CI -2.1;-0.4 , p = 0.01 ) , in comparison with usual care . The phone group appeared to have more and larger changes than the internet group , but comparisons revealed no significant differences . Conclusion Lifestyle counselling by phone and e-mail is effective for weight management  in overweight employees and shows potential for use in the work setting .Trial registration ISCRTN04265725 CONTEXT Rapid increases in access to the Internet have made it a viable mode for public health intervention . No controlled studies have evaluated this re source for weight loss . OBJECTIVE To determine whether a structured Internet behavioral weight loss program produces greater initial weight loss and changes in waist circumference than a weight loss education Web site . DESIGN R and omized , controlled trial conducted from April to December 1999 . SETTING AND PARTICIPANTS Ninety-one healthy , overweight adult hospital employees aged 18 to 60 years with a body mass index of 25 to 36 kg/m(2 ) . Analyses were performed for the 65 who had complete follow-up data . INTERVENTIONS Participants were r and omly assigned to a 6-month weight loss program of either Internet education ( education ; n = 32 with complete data ) or Internet behavior therapy ( behavior therapy ; n = 33 with complete data ) . All participants were given 1 face-to-face group weight loss session and access to a Web site with organized links to Internet weight loss re sources . Participants in the behavior therapy group received additional behavioral procedures , including a sequence of 24 weekly behavioral lessons via e-mail , weekly online su bmi ssion of self-monitoring diaries with individualized therapist feedback via e-mail , and an online bulletin board . MAIN OUTCOME MEASURES Body weight and waist circumference , measured at 0 , 3 , and 6 months , compared the 2 intervention groups . RESULTS Repeated- measures analyses showed that the behavior therapy group lost more weight than the education group ( P = .005 ) . The behavior therapy group lost a mean ( SD ) of 4.0 ( 2.8 ) kg by 3 months and 4.1 ( 4.5 ) kg by 6 months . Weight loss in the education group was 1.7 ( 2.7 ) kg at 3 months and 1.6 ( 3.3 ) kg by 6 months . More participants in the behavior therapy than education group achieved the 5 % weight loss goal ( 45 % vs 22 % ; P = .05 ) by 6 months . Changes in waist circumference were also greater in the behavior therapy group than in the education group at both 3 months ( P = .001 ) and 6 months ( P = .005 ) . CONCLUSIONS Participants who were given a structured behavioral treatment program with weekly contact and individualized feedback had better weight loss compared with those given links to educational Web sites . Thus , the Internet and e-mail appear to be viable methods for delivery of structured behavioral weight loss programs Background Rising levels of obesity coupled with the limited success of currently available weight control methods highlight the need for investigation of novel approaches to obesity treatment . This study aims to determine the effectiveness and cost-effectiveness of an Internet-based re source for obesity management . Methods A r and omised controlled trial conducted in a community setting , where obese volunteers ( n = 221 ) were r and omly assigned to  Internet group ( n = 111 ) or usual care group ( n = 110 ) . Objective measures of weight and height were obtained . Question naires were used to collect dietary , lifestyle , physical activity and quality of life data . Data were collected at baseline , six months and 12 months . Results Data were collected on 54 ( 49 % ) participants in the Internet group and 77 ( 70 % ) participants in the usual care group at 12 months . Based on analysis conducted on all available data , the Internet group lost 1.3 kg , compared with 1.9 kg weight loss in the usual care group at 12 months , a non-significant difference ( difference = 0.6 kg ; 95 % CI : -1.4 to 2.5 , p = 0.56 ) . No significant differences in change in secondary outcome measures between the two groups at six or 12 months were revealed . Total costs per person per year were higher in the Internet group than the usual care group ( £ 992.40 compared to £ 276.12 ) , primarily due to the fixed costs associated with setting up the website , and QALYs were similar ( 0.78 and 0.77 ) for both groups . Conclusion This trial failed to show any additional benefit of this website in terms of weight loss or secondary outcome measures compared with usual care . High attrition and low compliance limits the results of this research . The results suggest that the Internet-based weight control re source was not a cost-effective tool for weight loss in the obese sample studied . Trail Registration IS RCT N BACKGROUND Several studies have shown that e-mail counseling improves weight loss achieved in self-directed Internet programs . Computer-tailored feedback offers a population -based alternative to human e-mail counseling . METHODS One hundred ninety-two adults , aged 49.2 + /- 9.8 years , having a body mass index ( calculated as weight in kilograms divided by height in meters squared ) of 32.7 + /- 3.5 , were r and omized to 1 of 3 Internet treatment groups : No counseling , computer-automated feedback , or human e-mail counseling .  All participants received 1 weight loss group session , coupons for meal replacements , and access to an interactive Web site . The human e-mail counseling and computer-automated feedback groups also had access to an electronic diary and message board . The human e-mail counseling group received weekly e-mail feedback from a counselor , and the computer-automated feedback group received automated , tailored messages . RESULTS Retention was 82 % at 3 months and 80 % at 6 months for all 3 groups . At 3 months , completers in both the computer-automated feedback ( -5.3 + /- 4.2 kg ) and human e-mail counseling ( -6.1 + /- 3.9 kg ) groups had significantly greater weight losses compared with the no counseling group ( -2.8 + /- 3.5 kg ) and these groups did not differ from each other . At 6 months , weight losses were significantly greater in the human e-mail counseling group ( -7.3 + /- 6.2 kg ) than in the computer-automated feedback ( -4.9 + /- 5.9 kg ) or no counseling ( -2.6 + /- 5.7 kg ) groups . Intent-to-treat analyses using single or multiple imputation techniques showed the same pattern of significance . CONCLUSIONS Providing automated computer-tailored feedback in an Internet weight loss program was as effective as human e-mail counseling at 3 months . Further research is needed to improve the efficacy of automated computer-tailored feedback as a population -based weight loss approach Purpose . To evaluate minimal-contact and telephone-assisted weight-loss programs for overweight persons . Design . Participants were r and omized to a minimal-contact group or one of two telephone-assisted weight-loss groups .  All participants attended two group-based behavioral weight-loss classes and received written educational material s and diaries . For the subsequent 24 weeks , the minimal-contact group received no contact and the telephone-assisted group members received weekly calls to monitor their weight , food intake , and exercise . Setting . Baseline educational sessions and data collection were conducted at a university site . Subjects . Sixty-four healthy subjects ( 4 men ) who were from 120 % to 150 % of ideal weight and were 25 to 55 years of age participated in the study . Measures . The major outcome of interest was change in measured weight over a 24-week period Data on calories expended in exercise , dietary intake , and demographics were also gathered at baseline and 24 weeks . Results . Weight loss did not differ significantly by treatment . Unexpectedly , the minimal-contact group lost almost twice as much weight as the telephone-assisted groups ( 12.7 vs 7.9 lb ) . Conclusions . There appears to be an audience for low-contact and telephone-assisted weight-loss programs , and such programs can be delivered easily . However , because the data show only modest weight-loss success , work should continue to identify the optimal content and design of such interventions BACKGROUND Since many successful dieters regain the weight they lose , programs that teach maintenance skills are needed . We developed a maintenance program based on self-regulation theory and tested the efficacy of delivering the program face to face or over the Internet . METHODS We r and omly assigned 314 participants who had lost a mean of 19.3 kg of body weight in the previous 2 years to one of three groups : a control group , which received quarterly newsletters ( 105 participants ) , a group that received face-to-face intervention ( 105 ) , and a group that received Internet-based intervention ( 104 ) . The content of the programs in the two intervention groups was the same , emphasizing daily self-weighing and self-regulation , as was the frequency of contact with the groups . The primary outcome was weight gain over a period of 18 months . RESULTS The mean ( + /-SD ) weight gain was 2.5+/-6.7 kg in the face-to-face group , 4.7+/-8.6 kg in the Internet group , and 4.9+/-6.5 kg in the control group , with a significant difference between the face-to-face group and the control group ( 2.4 kg ; 95 % confidence interval [ CI ] , 0.002 to 10.8 ; P=0.05 ) . The proportion of participants who regained 2.3 kg or more over the 18-month period was significantly higher in the control group ( 72.4 % ) than in the face-to-face group ( 45.7 % ; absolute difference , 27 % ; 95 % CI , 14 to 39 ; P<0.001 ) or the Internet group ( 54.8 % ; absolute difference , 18 % ; 95 % CI , 5 to 30 ; P=0.008 ) . Daily self-weighing increased in both intervention groups and was associated with a decreased risk of regaining 2.3 kg or more ( P<0.001 ) . CONCLUSIONS As compared with receiving quarterly newsletters , a self-regulation program based on daily weighing improved maintenance of weight loss , particularly when delivered face to face . ( Clinical Trials.gov number , NCT00067145 [ Clinical Trials.gov ] . This experiment evaluated the efficacy of television delivery of a  behavioral weight reduction program .  Seventy-one overweight adults were r and omly assigned to a live-contact weight loss group that was videotaped for viewing by other groups , a live-contact group that was not videotaped , a television-delivered group that observed the videotaped weight loss sessions , or a waiting-list control group . Participants in all 3 treatment groups lost significantly more weight during the 8-week treatment program than those in the waiting-list control group . There was no significant weight loss differences among the 3 treatment groups during the program . These weight changes were maintained at 3-month follow-up . At 15-month follow-up , the television-delivered group and the live-contact group maintained their weight losses , whereas the videotaped group did not . Cost-effectiveness analyses indicated that the television-delivered group received the most cost-effective treatment Purpose : The increased availability and use of the Internet by midlife and older women who seek health information may provide an innovative method for delivering weight loss interventions . This 
    Output:
    
An examination of effect sizes show that the higher significant effects pertain studies that found a superiority of behavioral internet-based programs enhanced by features such as tailored feedback on self-monitoring of weight , eating and activity  over education only internet-based interventions .
Hence , questions still remain as to the effectiveness  of  web-based interventions in achieving weight loss or maintenance .