***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 Research increasingly supports the conclusion that well- design ed programs delivered over the Internet can produce significant weight loss compared to r and omized controlled conditions . Much less is known about four important issues addressed in this study : ( 1 ) which recruitment methods produce higher eHealth participation rates , ( 2 ) which patient characteristics are related to enrollment , ( 3 ) which characteristics are related to level of user engagement in the program , and ( 4 ) which characteristics are related to continued participation in project assessment s. Methods We recruited overweight members of three health maintenance organizations ( HMOs ) to participate in an entirely Internet-mediated weight loss program developed by HealthMedia , Inc.  Two different recruitment methods were used : personal letters from prevention directors in each HMO , and general notices in member newsletters . The personal letters were sent to members diagnosed with diabetes or heart disease and , in one HMO , to a general membership sample in a particular geographic location . Data were collected in the context of a 2 × 2 r and omized controlled trial , with participants assigned to receive or not receive a goal setting intervention and a nutrition education intervention in addition to the basic program . Results A total of 2311 members enrolled . Bivariate analyses on aggregate data revealed that personalized mailings produced higher enrollment rates than member newsletters and that members with diabetes or heart disease were more likely to enroll than those without these diagnoses . In addition , males , those over age 60 , smokers , and those estimated to have higher medical expenses were less likely to enroll ( all P < .001 ) . Males and those in the combined intervention were less likely to engage initially , or to continue to be engaged with their Web program , than other participants . In terms of retention , multiple logistic regressions revealed that enrollees under age 60 ( P < .001 ) and those with higher baseline self-efficacy were less likely to participate in the 12-month follow-up ( P = .03 ) , but with these exceptions , those participating were very similar to those not participating in the follow-up . Conclusions A single personalized mailing increases enrollment in Internet-based weight loss . eHealth programs offer great potential for recruiting large numbers of participants , but they may not reach those at highest risk . Patient characteristics related to each of these important factors may be different , and more comprehensive analyses of determinants of enrollment , engagement , and retention in eHealth programs are needed Overweight and physical inactivity are associated with elevated reactive oxygen species and chronic low- grade inflammation . Exercise training studies have measured changes in systemic inflammatory and oxidative/antioxidative biomarkers but predominantly at moderate-high intensities . Few low-intensity , lifestyle-based physical activity ( PA ) studies have been conducted . The purpose of this study was to determine whether improvements in lifestyle-oriented PA result ing from a 16-wk Internet-delivered PA program [ Active Living Every Day-Internet ( ALED-I ) ] elicit cardioprotective improvements in measures of inflammation , oxidation , or antioxidant enzyme capacity .  Forty-one men and women ( age 23 - 62 yr ) were r and omized to either the ALED-I intervention [ n = 19 ; age = 40.4 + /- 1.9 yr ; body mass index ( BMI ) = 31.4 + /- 1.1 kg/m(2 ) ] or a delayed intent-to-treat control condition ( n = 22 ; age = 46.6 + /- 1.3 yr ; BMI = 31.0 + /- 0.7 kg/m(2 ) ) . TNF-alpha , C-reactive protein , myeloperoxidase , superoxide dismutase , catalase , total antioxidative capacity , change in PA , and other cardiometabolic disease risk factors were measured at baseline and postintervention . The ALED-I group increased PA and decreased central adiposity without changes in the control group . There was no change in the control group for any inflammation , oxidation , or antioxidant biomarkers . TNF-alpha decreased ( P = 0.01 ) in the intervention group but was not statistically different from the control group . In conclusion , modest improvements in daily low-intensity ambulatory PA as a result of an Internet-delivered lifestyle PA intervention may be cardioprotective in sedentary and overweight adults through reductions in central adiposity and inflammation . However , the absence of favorable changes in other inflammation , oxidation , and antioxidant biomarkers highlights the need for further attention to the dose response of lifestyle-structured PA promotion strategies for health maintenance/improvement The transition to college has been identified as a critical period for increases in overweight status . Overweight college students are at-risk of becoming obese adults , and , thus prevention efforts targeting college age individuals are key to reducing adult obesity rates . The current study evaluated an Internet intervention with first year college students ( N=170 ) r and omly assigned to one of four treatment conditions : 1 ) no treatment , 2 ) 6-week online intervention 3 ) 6-week weight and caloric feedback only ( via email ) , and 4 ) 6-week combined feedback and online intervention . The combined intervention group had lower BMI s at post-testing than the other three groups . This study demonstrated the effectiveness and feasibility of an online intervention to prevent weight gain among college students 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 Background Overweight ( Body Mass Index [ BMI ] ≥ 25 kg/m2 ) and obesity ( BMI ≥ 30 kg/m2 ) are associated with increased cardiovascular risk , posing a considerable burden to public health . The main aim of this study was to investigate lifestyle intervention effects on cardiovascular risk factors in healthy overweight employees . Methods Participants were 276 healthy overweight employees ( 69.2 % male ; mean age 44.0 years [ SD 9.2 ] ; mean BMI 29.7 kg/m2 [ SD 3.1 ] ) . They were r and omized to one of two intervention groups receiving a six month lifestyle intervention with behavior counseling by phone ( phone group ) or e-mail ( Internet group ) , or to a control group receiving usual care .  Body weight , height , waist circumference , sum of skinfolds , blood pressure , total cholesterol level and predicted aerobic fitness were measured at baseline , at 6 and at 24 months . Regression analyses included the 141 participants with complete data . Results At 6 months a significant favorable effect on total cholesterol level ( -0.2 mmol/l , 95%CI -0.5 to -0.0 ) was observed in the phone group and a trend for improved aerobic fitness ( 1.9 ml/kg/min , 95%CI -0.2 to 3.9 ) in the Internet group . At two years , favorable trends for body weight ( -2.1 kg , 95%CI -4.4 to 0.2 ) and aerobic fitness ( 2.3 ml/kg/min , 95%CI -0.2 to 4.8 ) were observed in the Internet group . Conclusions The intervention effects were independent of the used communication mode . However short-term results were in favor of the phone group and long-term results in favor of the internet group . Thus , we found limited evidence for our lifestyle intervention to be effective in reducing cardiovascular risk in a group of apparently healthy overweight workers . Trial registration IS RCT Background There has been increasing interest in the ability of the internet to produce behaviour change . The focus of this study was to describe program exposure across three intervention groups from a r and omised trial ( RT ) comparing traditional face-to-face , internet-mediated ( combined internet plus face-to-face ) , and internet-only program delivery . Methods Baseline and immediately post-intervention survey data , and exposure rates from participants that commenced the RT were included ( n = 192 ) . Exposure was defined as either face-to-face attendance , website usage , or a combination of both for the internet-mediated group . Characteristics of participants who were exposed to at least 75 % of the program material were explored . Descriptive analysis and logistical regression were used to examine differences between groups for program exposure . Results All groups showed decrease in program exposure over time . Differences were also observed ( χ2 = 10.37 , p < 0.05 ) , between intervention groups . The internet-mediated ( OR = 2.4 , 95 % CI 1.13–5.1 ) and internet-only ( OR = 2.96 , 95 % CI 1.38–6.3 ) groups were more likely to have been exposed to at least 75 % of the program compared to the face-to-face group . Participants with high physical activity self-efficacy were 1.82 ( 95 % CI 1.15–2.88 ) times more likely to have been exposed to 75 % of the program , and those allocated to the face-to-face group were less likely to have attended 75 % of the face-to-face sessions if they were classified as obese ( OR = 0.21 95 % CI 0.04–0.96 ) . Conclusion These results suggest that the internet groups were as effective as the face-to-face delivery mode in engaging participants in the program material . However , different delivery methods may be more useful to different sub- population s. It is important to explore which target groups that internet-based programs are best suited , in order to increase their impact 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 
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AUTHORS ' CONCLUSIONS Compared to no intervention or minimal interventions ( pamphlets , usual care ) , interactive computer-based interventions are an effective intervention for weight loss and weight maintenance .
Compared to in-person interventions , interactive computer-based interventions result in smaller weight losses and lower levels of weight maintenance .
The amount of additional weight loss , however , is relatively small and of brief duration , making the clinical significance of these differences unclear