***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: A r and omised control trial evaluated the effectiveness of a theory-based persuasive leaflet design ed to encourage students to undertake at least one additional physical exercise session a week . Participants were 503 secondary school students attending a school in South-East Engl and . The leaflet was written to target potentially modifiable cognitive antecedents of exercise specified by the Theory of Planned Behaviour . It was separately augmented with two cognitive change techniques , result ing in three intervention conditions , leaflet alone ; leaflet plus motivational quiz , and leaflet plus implementation intention prompt , as well as a no-leaflet control condition .  Cognitions and behaviour were measured immediately before and 3 weeks after intervention . The results showed that all three-leaflet interventions significantly increased reported exercise , intention to exercise and related cognitions , compared to the control condition , but did not differ in their impact . Mediation analysis showed that intervention effects on exercise were partially mediated by intentions and perceived behavioural control OBJECTIVES ICAPS ( Intervention Centred on Adolescents ' Physical activity and Sedentary behaviour ) is aim ed at preventing excessive weight gain and cardiovascular risk in adolescents by promoting physical activity ( PA ) with an emphasis on recreational and daily-life PA , with a lifelong perspective . DESIGN R and omized study design ed to last for four years . Study cohort constituted of 954 first-level students ( 91 % of eligible pupils ) , aged 11.7 + /- 0.6 y ( mean + /- SD ) from four pairs of schools r and omly selected in eastern France , after sociogeographical stratification . In each pair , intervention status was r and omised at school-level . The program , not limited to school setting s , involves multiple partners with three objectives : 1 ) changing attitudes through debates and access to attractive activities during breaks and after-school hours , 2 ) encouraging social support , 3 ) providing environmental conditions that enable PA . Adapted times and places , open participation , emphasis on fun , meeting with others and absence of competitive aspects are used to reduce usual barriers to PA .  Accessibility and safety are permanent concerns . RESULTS Prevalence of overweight was 23.7 % . High participation rates were attained ( 50 % participated in at least one weekly activity ) . At six-month , the proportion of intervention adolescents  not performing supervised PA out of academic PA  was reduced by half ( 36 % to 17 % vs 42 % to 42 % in controls P < 10 - 4 ) ; the proportion of those spending > 3 h/day in sedentary occupations decreased ( 34 % to 28 % vs 27 % to 36 % ; P < 10 - 4 ) . CONCLUSION These data demonstrate the feasibility of implementing a multilevel PA intervention program in adolescents . Six-month results document increased PA  and decreased sedentary behaviour Abstract Objectives : To evaluate the effectiveness of inviting teenagers to  general practice consultations to discuss health behaviour concerns and appropriate follow up care . Design : R and omised controlled trial , with participants r and omised to a consultation ( intervention ) or usual care ( control ) . Question naires completed at baseline , 3 months , and 12 months . Setting : Eight general practice s in Hertfordshire , Engl and . Participants : 1516 teenagers aged 14 - 15 years . Intervention : Consultations with practice nurses to discuss health concerns and develop plans for healthier lifestyles . Main outcome measures : Mental and physical health , “ stage of change ” for health related behaviour , and use of health services . Results : At baseline 970 teenagers completed question naires ; 23 % smoked , 35 % had been drunk in the previous three months , 64 % considered they ate unhealthily , 39 % took little exercise , and 36 % had possible depression . 41 % ( 304 ) of teenagers invited attended for a consultation ; over one third ( 112 ) were offered follow up care . More intervention group teenagers reported positive movement in stage of change for diet and exercise and in at least one of four behaviours ( diet , exercise , smoking , drinking alcohol ) at 3 months ( 41 % v 31 % , P<0.01 ) , but this did not persist at 12 months . There was marginally more positive change in actual behaviour by intervention teenagers at 3 months ( 16 % v 12 % , P=0.06 ) . Recognition of possible depression result ed in improved mental health outcomes at 3 and 12 months . 97 % of attenders said they would recommend the intervention to a friend . Conclusions : Change in behaviour was slight but encouraging , and the intervention was well received and relatively cheap Interventions to promote physical activity are important in preventing children from becoming overweight . Many projects have been developed but only a few showed ( moderate ) effects . JUMP-in is a systematic ally developed primary -school-based intervention that focuses on the use of theory , environmental changes , parental influences and cooperation with multi-level parties in intervention development . The effects of JUMP-in were evaluated with a quasi-experimental pre-test/post-test research design . In total , 510 children from Grade s 4 , 5 and 6 of four intervention schools and two control schools in Amsterdam were followed for an intervention period of one school year . Changes in physical activity as well as in the social cognitive determinants were assessed using self-reports . In addition , a process evaluation has been executed . The results show that JUMP-in was effective in influencing physical activity , especially among children from Grade 6 . Children in the control group decreased their level of physical activity considerably , while activity levels in intervention children from Grade 6 remained stable . The intervention effects could not be explained by changes in the measured social cognitive determinants . In contrast , process information illuminated differences in intervention effects between the participating schools . The results from the JUMP-in study show the importance of intervention design s that focus on a theory-based mix of relevant environmental and social cognitive factors Physical activity levels in young adults are low . Research supports the use of the Transtheoretical Model of behaviour change ( TM ) in design ing physical activity interventions . This study used a pre-post r and omized control design to investigate the effectiveness of a self-instructional intervention for helping sedentary young adults to initiate physical activity . Post-intervention , significantly more of the experimental group ( 80 % ) , in comparison to the control group ( 68 % ) , improved their exercise stage of change ( SOC ) from baseline ( P < 0.05 ) . Discriminant analyses revealed that discrimination between stage improvement/non-improvement was possible using the processes of change data . Stage improvers scored significantly higher on all of the behavioral and four out of five of the cognitive processes of change . For stage improvers , the processes of self-re-evaluation and self-liberation were most frequently used , whilst social liberation was used significantly more by the experimental than the control group . This inexpensive , self-instructional intervention , based on the TM and the ' active living message ' , is an effective method of assisting sedentary young adults to progress through the exercise SOC Low levels of physical activity coupled with high levels of television viewing have been linked with obesity in children . The objective of this study was to assess the efficacy of ' Switch Off-Get Active ' , a 16-week controlled health education intervention , in increasing physical activity and reducing screen time and BMI in primary school children . A secondary objective was to compare children with high and low screen time . Participants were 312 children aged 10.2+/-0.7 years , attending nine schools in areas of social disadvantage . The 10-lesson , teacher-led intervention , conducted in spring 2003 , emphasised self-monitoring , budgeting of time and selective viewing . Differences , adjusted for baseline values by ANCOVA , existed between intervention and control children at follow-up for self-reported physical activity ( intervention + 0.84 30 min blocks/day , 95%CI 0.11 - 1.57 , p<0.05 ) and self-efficacy for physical activity ( p<0.05 ) but not self-reported screen time ( intervention--0.41 blocks/day , 95%CI--0.93 - 0.12 , p=0.13 ) or BMI ( p=0.63 ) . Cross-sectional comparisons at baseline indicated lower physical activity , self-efficacy for physical activity and aerobic fitness and a higher BMI in children with high screen time . In conclusion , health education interventions can increase physical activity in primary school children but follow-ups of longer duration may be needed to demonstrate intervention effects on BMI Background Aim ing at an active lifestyle , healthy food habits and non-smoking among Swedish children , the Swedish Heart Lung Foundation initiated the health educational programme ‘ An adventure with Pelle Pump ' . A study kit , including theoretical and practical material on heart-lung function and healthy behaviour , was offered to all fourth grade rs in Sweden . The impact of the programme was examined by study ing health behaviours and health knowledge among programme participants using non- participants as a control population . Methods A question naire on health behaviour and health knowledge was answered by a r and om sample of 1369 children from different social classes and living conditions . Children subjected to the programme formed the  programme group ( n = 523 ) and those without exposure  served as a control group ( n = 846 ) . Results Children in the programme group had a significantly higher level of knowledge ( P < 0.001 ) on questions relating to health behaviour and bodily functions . The actual health behaviour was , however , not affected by the programme . Conclusion Children exposed to a health education programme had , compared with a control population , 2 years after completing the programme , an increased level of knowledge ; however , no difference was found in health behaviour PURPOSE To evaluate the effects of a  middle school physical activity intervention , new in combining an environmental and computer tailored component ; and to evaluate the effects of parental involvement . METHODS A clustered r and omized controlled design was used . A r and om sample of 15 schools with 7th and 8th grade rs was r and omly assigned to one of three conditions : ( a ) intervention with parental support , ( b ) intervention alone , and ( c ) control group . The intervention was new in combining environmental strategies with computer-tailored feedback to increase levels of moderate to vigorous physical activity .  The intervention was implemented by the school staff . Physical activity was measured through a question naire in the total sample and with accelerometers in a sub sample of adolescents . RESULTS The intervention with parental support led to an increase in self-reported school-related physical activity of , on average , 6.4 minutes per day ( p < or = .05 , d = .40 ) . Physical activity of light intensity measured with accelerometers decreased with , on average , 36 minutes per day as a result of the intervention with parental support ( p < or = .05 , d = .54 ) . Physical activity of moderate to vigorous intensity measured with accelerometers significantly increased with on average 4 minutes per day in the intervention group with parental support , while it decreased with almost 7 minutes per day in the control group ( p < or = .05 , d = .46 ) . CONCLUSIONS The physical activity intervention , implemented by the school staff , result ed in enhanced physical activity behaviors in both middle school boys and girls . The combination of environmental approaches with computer-tailored interventions seemed promising OBJECTIVE To evaluate acceptability , feasibility and effectiveness of computer-tailored physical activity education among adolescents . METHODS Two classes of 7th grade rs from 10 r and omly selected schools were assigned to the intervention ( computer-tailored intervention , n=139 ) or control ( no-intervention , n=142 ) condition . Question naires were completed 1 week before and 3 months after the intervention . The computer-tailored intervention was completed during classes . RESULTS Students had few problems with the diagnostic questions and with the use of a computer . About half of the students evaluated the advice as interesting and easy to underst and and about 40 % as personally relevant , easy to use and credible . Half of students evaluated the advice as too long and only 33 % reported to have used the advice . The computer-tailored intervention was effective for increasing school related physical activity levels with on average 25 min per week ( F=3.4 , P < or = .05 ) , but not for increasing total physical activity or leisure time physical activity . CONCLUSIONS A 1-h computer-tailored intervention offered during class-time has the potential to increase school related physical activity . PRACTICE IMPLICATION S Although favourable effects of large scale implementation may be expected , some adaptations that might increase effectiveness should be investigated in the future PURPOSE To investigate the effect of a six-month teacher-led osteogenic physical activity program , vs. a self-led activity program , on ultrasound measurements of bone in inactive teenage girls . METHODS Ninety sedentary girls [ mean ( SD ) age 16.3 ( .6 ) years ] were identified from 300 assessed for physical activity across five schools in southeast Irel and . Schools were matched and r and omly assigned to a teacher-led physical activity ( TLPA ) program , a self-led physical activity ( SLPA ) program , or a control group .  Broadb and ultrasound attenuation ( BUA ) , speed of sound ( SOS ) , and os calcis stiffness index ( OCSI ) were measured using a portable ultrasound machine . Anthropometry , aerobic fitness , calcium intake , and physical activity were assessed , and focus groups held one month after program completion . Descriptive statistics , paired t-tests , and analysis of variance were used to analyze the data . RESULTS Both intervention groups demonstrated significant improvements ( p < .05 ) in BUA , SOS , OCSI and aerobic fitness , i.e. , TLPA : + 14.9 % , + 21.9 % , + 15.9 % , and + 8.5 % , respectively , and SLPA : + 10.6 % , + 30.3 % , + 15.6 % , and + 5.1 % , respectively , with no change in controls . Differences between intervention groups and controls were significant for BUA and OCSI ( p < .0 
    Output:
    
The main findings based on this evidence were : ( 1 ) school-based interventions generally lead to short term improvement in physical activity levels , but there were large differences between interventions with regard to effect sizes ; ( 2 ) a multi-component approach ( including environmental components ) generally result ed in larger effect sizes , thereby providing evidence for the assumption that a multi-component approach should produce synergistic results ; and ( 3 ) if an intervention aim ed to affect more health behaviours besides physical activity , then the intervention appeared to be less effective in favour of physical activity