human
***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 Supporting 21st century health care and the practice of evidence -based medicine ( EBM ) requires ubiquitous access to clinical information and to knowledge-based re sources to answer clinical questions . Many questions go unanswered , however , due to lack of skills in formulating questions , crafting effective search strategies , and accessing data bases to identify best levels of evidence . Methods This r and omized trial was design ed as a pilot study to measure the relevancy of search results using three different interfaces for the PubMed search system . Two of the search interfaces utilized a specific framework called PICO , which was design ed to focus clinical questions and to prompt for publication type or type of question asked . The third interface was the st and ard PubMed interface readily available on the Web . Study subjects were recruited from interns and residents on an inpatient general medicine rotation at an academic medical center in the US . Thirty-one subjects were r and omized to one of the three interfaces , given 3 clinical questions , and asked to search PubMed for a set of relevant articles that would provide an answer for each question . The success of the search results was determined by a precision score , which compared the number of relevant or gold st and ard articles retrieved in a result set to the total number of articles retrieved in that set . Results Participants using the PICO templates ( Protocol A or Protocol B ) had higher precision scores for each question than the participants who used Protocol C , the st and ard PubMed Web interface . ( Question 1 : A = 35 % , B = 28 % , C = 20 % ; Question 2 : A = 5 % , B = 6 % , C = 4 % ; Question 3 : A = 1 % , B = 0 % , C = 0 % ) 95 % confidence intervals were calculated for the precision for each question using a lower boundary of zero . However , the 95 % confidence limits were overlapping , suggesting no statistical difference between the groups . Conclusion Due to the small number of search es for each arm , this pilot study could not demonstrate a statistically significant difference between the search protocol s. However there was a trend towards higher precision that needs to be investigated in a larger study to determine if PICO can improve the relevancy of search results Background The question of whether air pollution contributes to asthma onset remains unresolved . Objectives In this study , we assessed the association between  asthma onset in children and traffic-related air pollution . Methods We selected a sample of 217 children from participants in the Southern California Children ’s Health Study , a prospect i ve cohort design ed to investigate associations between air pollution and respiratory health in children 10–18 years of age . Individual covariates and new asthma incidence ( 30 cases ) were reported annually through question naires during 8 years of follow-up . Children had nitrogen dioxide monitors placed outside their home for 2 weeks in the summer and 2 weeks in the fall – winter season as a marker of traffic-related air pollution . We used multilevel Cox models to test the associations between asthma and air pollution . Results In models controlling for confounders , incident asthma was positively associated with traffic pollution , with a hazard ratio ( HR ) of 1.29 [ 95 % confidence interval ( CI ) , 1.07–1.56 ] across the average within-community interquartile range of 6.2 ppb in annual residential NO2 . Using the total interquartile range for all measurements of 28.9 ppb increased the HR to 3.25 ( 95 % CI , 1.35–7.85 ) . Conclusions In this cohort , markers of traffic-related air pollution were associated with the onset of asthma . The risks observed suggest that air pollution exposure contributes to new-onset asthma Background Physical inactivity  among children is an increasing problem that adversely affects children ’s health . A better underst and ing of factors which affect  physical activity ( PA ) will help create effective interventions aim ed at raising the activity levels of children . This cross-sectional study examined the associations of PA with individual ( biological , social , behavioral , psychological ) and environmental ( East vs. West Germany , rural vs. urban regions ) characteristics in children . Methods Information on PA and potential correlates was collected from 1843 girls and 1997 boys using question naires during the 10-year follow-up of two prospect i ve birth cohort studies ( GINIplus and LISAplus ) . Study regions represent urban and rural sites as well as East and West of Germany . Logistic regression modeling was applied to examine cross-sectional associations between individual as well as environmental factors and  PA levels . Results Five of fourteen variables were significantly associated with  PA .  Among children aged 10 , girls tended to be less active than boys , especially with respect to vigorous PA ( OR = 0.72 for summer ) . Children who were not a member of a sports club showed a substantially reduced amount of PA in winter ( OR = 0.15 ) . Rural environments promote moderate PA  , particularly in winter ( OR = 1.88 ) , whereas an increased time outdoors primarily promotes moderate PA in summer ( OR = 12.41 ) . Children with abnormal emotional symptoms  exhibited reduced physical activity , particularly in winter ( OR = 0.60 ) . BMI , puberty , parental BMI , parental education , household income , siblings , TV/PC consumption , and method of arriving school , were not associated with PA . Conclusions When considering correlates of PA from several domains simultaneously , only few factors ( sex , sports club membership , physical environment , time outdoors , and emotional symptoms ) appear to be relevant . Although the causality needs to be ascertained in longitudinal studies , variables which can not be modified should be used to identify risk groups while modifiable variables , such as sports club activities , may be addressed in intervention programs Background The pre-school years are considered critical for establishing healthy lifestyle behaviours such as physical activity . Levels of physical activity track through childhood into adulthood , thus establishing habitual physical activity early in life is vital . Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school aged children . There are few pre-school , playground-based interventions , and evaluations of these have found mixed results . A recent report published by the UK Chief Medical Officer ( CMO ) highlighted that new interventions to promote movement in the early years ( 0–5 years old ) are needed . The aim of this study is to undertake a pilot cluster r and omised controlled trial ( RCT ) of an outdoor playground-based physical activity intervention for parents and their children aged 18 months to 4 years old ( “ Pre-schoolers in the Playground ” ; PiP ) and to assess the feasibility of conducting a full scale cluster RCT . The PiP intervention is grounded in behavioural theory ( Social Cognitive Theory ) , and is in accordance with the CMO guidance for physical activity in the early years . It is informed by existing literature and data collected from focus groups with parents . Methods / Design One hundred and fifty pre-school children affiliated to 10 primary schools will be recruited . Schools will be r and omised to either the PiP intervention arm or the control arm ( usual practice ) . Children in the intervention arm will be invited to attend three 30 minute outdoor play sessions per week for 30 weeks ( 3 school terms ) at the school . Feasibility will be assessed by examining recruitment rates , attendance , attrition , acceptability of the trial and of the PiP intervention to parents , fidelity of intervention implementation , capability and capacity for schools to deliver the intervention . Health outcomes and the feasibility of outcome measurement tools will be assessed . These include physical activity via triaxial , accelerometry ( Actigraph GT3X+ ) , anthropometry ( height , body mass , BMI , waist and upper arm circumference ) , health related quality of life for child ( PedsQL ) and parent ( EQ5D ) , parent wellbeing ( ComQol-A5 ) , injuries and health service use . A health economic evaluation will also be undertaken . Discussion It is anticipated that results of this pilot trial will be published in spring 2015.Trial registration Current controlled trials : IS RCT Elevated blood pressure ( BP ) during childhood and adolescence increases the risk of hypertension in later life . Although physical activity is known to positively moderate BP , data regarding this relationship are limited in prepubertal children . We aim ed to assess the association between a range of physical activities ( including indoor and outdoor activity ) and BP in a large community-based sample of prepubertal schoolchildren . Eligible year-1 schoolchildren ( n=1765 ; mean age 6.7±0.4 years ) from a r and om cluster sample of 34 schools in Sydney , Australia , were examined .  Parents completed detailed question naires about their child 's activity . Height and weight were measured , and body mass index  ( BMI ) was calculated . BP was measured using a st and ard protocol , and elevated BP was defined using published guidelines . Physical activity was classified as low , medium or high ( that is , as tertiles ) . After adjusting for age , sex , ethnicity , height , BMI , parental qualifications and family history of hypertension and /or cardiovascular disease , children in the highest tertile of outdoor and indoor activities had significantly lower diastolic BP ( ∼1.5 mm Hg ; Ptrend=0.01 ) and systolic BP ( ∼1.3 mm Hg ; Ptrend=0.03 ) , respectively , compared with those in the lowest tertile ( reference ) . Linearly , time spent in indoor activities ( each hour per day ) was associated with ∼2.4 mm Hg decrease in diastolic BP ( P=0.001 ) . Physical activity was independently associated with lower BP in this sample of prepubertal children . The findings emphasize the importance of ensuring regular physical activity programs in primary schools to potentially reduce the risk of elevated BP in childhood and in later life Objective : This study aim ed to determine whether time spent outdoors was associated with objective ly measured physical activity , body mass index ( BMI ) z-score and overweight in elementary-school aged children , cross-sectionally and prospect ively over 3 years . Methods : Three-year cohort study with data collected during 2001 and 2004 . Nineteen r and omly selected state elementary schools across Melbourne , Australia . One hundred and eighty eight 5–6-year-old and 360 10–12-year-old children . Baseline parent reports of children 's time spent outdoors  during warmer and cooler months , on weekdays and weekends . At baseline and follow-up , children 's moderate and vigorous physical activity ( MVPA ) was objective ly assessed by accelerometry , and BMI z-score and overweight was calculated from measured height and weight . Results : Cross-sectionally , each additional hour outdoors on weekdays and weekend days during the cooler months was associated with an extra 27 min week−1 MVPA among older girls , and with an extra 20 min week−1 MVPA among older boys . Longitudinally , more time outdoors on weekends predicted higher MVPA on weekends among older girls and boys ( 5 min week−1 ) . The prevalence of overweight among older children at follow-up was 27–41 % lower among those spending more time outdoors at baseline . Conclusion : Encouraging 10–12-year-old children to spend more time outdoors may be an effective strategy for increasing physical activity and preventing increases in overweight and obesity . Intervention research investigating the effect of increasing time outdoors on children 's physical activity and overweight is warranted This study analyzed time-use interviews to report levels of active and inactive behavior  during the after-school period ( 3 - 6 pm ) . Interviews were conducted on r and om days from three separate seasons during third and fourth grade . Youth with at least two interviews during third ( 356 completed 2 interviews ; 506 completed 3 interviews [ 9 yrs ; 50 % boys ] ) and fourth ( 186 completed 2 interviews ; 768 completed 3 interviews [ 10 yrs ; 50 % boys ] ) grade were included to report levels of moderate-to-vigorous physical activity ( MVPA ) , light physical activity , inactive screen time  , inactive nonscreen time , and travel by location and who the activity was undertaken with .  Reporting time outside the home and with peers ( single or group ) was related to higher levels of MVPA . While inside the home , screen and nonscreen proportions were comparable ( 38 % and 40 % , respectively ) , despite unique patterns ( screen : boys > girls ; nonscreen : girls > boys ) . Reporting time with both parents was associated with more nonscreen time ; whereas reporting time with peer groups was associated with lower screen time . Underst and ing active and inactive patterns of children 's behavior outside of school hours can be very important in contributing toward the development of innovative interventions for increasing physical activity PURPOSE To evaluate an incentive-based intervention to increase time spent outdoors among children in a 9-month cluster r and omised controlled trial . METHODS Two hundred and eighty-five children aged 6 - 12 years of age were r and omised to the intervention ( n = 147 ) or control arm ( n = 138 ) in the Family incentive trial ( FIT ) . The FIT intervention comprised of targeted education on myopia and good eye care habits , structured weekend outdoor activities and incentives for children to increase their daily steps via pedometers . The main outcome measure was outdoor time , measured by the WHO question naire and a 1-week diary . RESULTS Interim analysis at 6 months showed a significant increase in mean outdoor time per week in the intervention arm ( 14.75 h week(-1 ) ) compared to the control arm ( 12.40 h week(-1 ) ) as measured by the question naire ( p = 0.04 ) . However , greater outdoor time was not statistically significant at the end of the trial ( 15.95 h week(-1 ) vs 14.34 h in the control group ( p = 0.29 ) . CONCLUSIONS There was an increase in outdoor time for children in the incentive-based physical activity outdoor program after 6 months but not at the end of the trial . Further larger school trials with better compliance with the intervention and longer duration could be conducted to evaluate clinical outcomes such as myopic shifts 
    Output:
    
agent
The systematic review revealed overall positive effects of outdoor time  on physical activity , sedentary behaviour , and cardiorespiratory fitness , although causality could not be assumed due to a lack of RCTs .
Motor skill development was unrelated to outdoor time ; however , this relationship was only examined in a single study of preschool children .
No studies were found that examined associations between outdoor time and musculoskeletal fitness
***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 Supporting 21st century health care and the practice of evidence -based medicine ( EBM ) requires ubiquitous access to clinical information and to knowledge-based re sources to answer clinical questions . Many questions go unanswered , however , due to lack of skills in formulating questions , crafting effective search strategies , and accessing data bases to identify best levels of evidence . Methods This r and omized trial was design ed as a pilot study to measure the relevancy of search results using three different interfaces for the PubMed search system . Two of the search interfaces utilized a specific framework called PICO , which was design ed to focus clinical questions and to prompt for publication type or type of question asked . The third interface was the st and ard PubMed interface readily available on the Web . Study subjects were recruited from interns and residents on an inpatient general medicine rotation at an academic medical center in the US . Thirty-one subjects were r and omized to one of the three interfaces , given 3 clinical questions , and asked to search PubMed for a set of relevant articles that would provide an answer for each question . The success of the search results was determined by a precision score , which compared the number of relevant or gold st and ard articles retrieved in a result set to the total number of articles retrieved in that set . Results Participants using the PICO templates ( Protocol A or Protocol B ) had higher precision scores for each question than the participants who used Protocol C , the st and ard PubMed Web interface . ( Question 1 : A = 35 % , B = 28 % , C = 20 % ; Question 2 : A = 5 % , B = 6 % , C = 4 % ; Question 3 : A = 1 % , B = 0 % , C = 0 % ) 95 % confidence intervals were calculated for the precision for each question using a lower boundary of zero . However , the 95 % confidence limits were overlapping , suggesting no statistical difference between the groups . Conclusion Due to the small number of search es for each arm , this pilot study could not demonstrate a statistically significant difference between the search protocol s. However there was a trend towards higher precision that needs to be investigated in a larger study to determine if PICO can improve the relevancy of search results Background The question of whether air pollution contributes to asthma onset remains unresolved . Objectives In this study , we assessed the association between  asthma onset in children and traffic-related air pollution . Methods We selected a sample of 217 children from participants in the Southern California Children ’s Health Study , a prospect i ve cohort design ed to investigate associations between air pollution and respiratory health in children 10–18 years of age . Individual covariates and new asthma incidence ( 30 cases ) were reported annually through question naires during 8 years of follow-up . Children had nitrogen dioxide monitors placed outside their home for 2 weeks in the summer and 2 weeks in the fall – winter season as a marker of traffic-related air pollution . We used multilevel Cox models to test the associations between asthma and air pollution . Results In models controlling for confounders , incident asthma was positively associated with traffic pollution , with a hazard ratio ( HR ) of 1.29 [ 95 % confidence interval ( CI ) , 1.07–1.56 ] across the average within-community interquartile range of 6.2 ppb in annual residential NO2 . Using the total interquartile range for all measurements of 28.9 ppb increased the HR to 3.25 ( 95 % CI , 1.35–7.85 ) . Conclusions In this cohort , markers of traffic-related air pollution were associated with the onset of asthma . The risks observed suggest that air pollution exposure contributes to new-onset asthma Background Physical inactivity  among children is an increasing problem that adversely affects children ’s health . A better underst and ing of factors which affect  physical activity ( PA ) will help create effective interventions aim ed at raising the activity levels of children . This cross-sectional study examined the associations of PA with individual ( biological , social , behavioral , psychological ) and environmental ( East vs. West Germany , rural vs. urban regions ) characteristics in children . Methods Information on PA and potential correlates was collected from 1843 girls and 1997 boys using question naires during the 10-year follow-up of two prospect i ve birth cohort studies ( GINIplus and LISAplus ) . Study regions represent urban and rural sites as well as East and West of Germany . Logistic regression modeling was applied to examine cross-sectional associations between individual as well as environmental factors and  PA levels . Results Five of fourteen variables were significantly associated with  PA .  Among children aged 10 , girls tended to be less active than boys , especially with respect to vigorous PA ( OR = 0.72 for summer ) . Children who were not a member of a sports club showed a substantially reduced amount of PA in winter ( OR = 0.15 ) . Rural environments promote moderate PA  , particularly in winter ( OR = 1.88 ) , whereas an increased time outdoors primarily promotes moderate PA in summer ( OR = 12.41 ) . Children with abnormal emotional symptoms  exhibited reduced physical activity , particularly in winter ( OR = 0.60 ) . BMI , puberty , parental BMI , parental education , household income , siblings , TV/PC consumption , and method of arriving school , were not associated with PA . Conclusions When considering correlates of PA from several domains simultaneously , only few factors ( sex , sports club membership , physical environment , time outdoors , and emotional symptoms ) appear to be relevant . Although the causality needs to be ascertained in longitudinal studies , variables which can not be modified should be used to identify risk groups while modifiable variables , such as sports club activities , may be addressed in intervention programs Background The pre-school years are considered critical for establishing healthy lifestyle behaviours such as physical activity . Levels of physical activity track through childhood into adulthood , thus establishing habitual physical activity early in life is vital . Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school aged children . There are few pre-school , playground-based interventions , and evaluations of these have found mixed results . A recent report published by the UK Chief Medical Officer ( CMO ) highlighted that new interventions to promote movement in the early years ( 0–5 years old ) are needed . The aim of this study is to undertake a pilot cluster r and omised controlled trial ( RCT ) of an outdoor playground-based physical activity intervention for parents and their children aged 18 months to 4 years old ( “ Pre-schoolers in the Playground ” ; PiP ) and to assess the feasibility of conducting a full scale cluster RCT . The PiP intervention is grounded in behavioural theory ( Social Cognitive Theory ) , and is in accordance with the CMO guidance for physical activity in the early years . It is informed by existing literature and data collected from focus groups with parents . Methods / Design One hundred and fifty pre-school children affiliated to 10 primary schools will be recruited . Schools will be r and omised to either the PiP intervention arm or the control arm ( usual practice ) . Children in the intervention arm will be invited to attend three 30 minute outdoor play sessions per week for 30 weeks ( 3 school terms ) at the school . Feasibility will be assessed by examining recruitment rates , attendance , attrition , acceptability of the trial and of the PiP intervention to parents , fidelity of intervention implementation , capability and capacity for schools to deliver the intervention . Health outcomes and the feasibility of outcome measurement tools will be assessed . These include physical activity via triaxial , accelerometry ( Actigraph GT3X+ ) , anthropometry ( height , body mass , BMI , waist and upper arm circumference ) , health related quality of life for child ( PedsQL ) and parent ( EQ5D ) , parent wellbeing ( ComQol-A5 ) , injuries and health service use . A health economic evaluation will also be undertaken . Discussion It is anticipated that results of this pilot trial will be published in spring 2015.Trial registration Current controlled trials : IS RCT Elevated blood pressure ( BP ) during childhood and adolescence increases the risk of hypertension in later life . Although physical activity is known to positively moderate BP , data regarding this relationship are limited in prepubertal children . We aim ed to assess the association between a range of physical activities ( including indoor and outdoor activity ) and BP in a large community-based sample of prepubertal schoolchildren . Eligible year-1 schoolchildren ( n=1765 ; mean age 6.7±0.4 years ) from a r and om cluster sample of 34 schools in Sydney , Australia , were examined .  Parents completed detailed question naires about their child 's activity . Height and weight were measured , and body mass index  ( BMI ) was calculated . BP was measured using a st and ard protocol , and elevated BP was defined using published guidelines . Physical activity was classified as low , medium or high ( that is , as tertiles ) . After adjusting for age , sex , ethnicity , height , BMI , parental qualifications and family history of hypertension and /or cardiovascular disease , children in the highest tertile of outdoor and indoor activities had significantly lower diastolic BP ( ∼1.5 mm Hg ; Ptrend=0.01 ) and systolic BP ( ∼1.3 mm Hg ; Ptrend=0.03 ) , respectively , compared with those in the lowest tertile ( reference ) . Linearly , time spent in indoor activities ( each hour per day ) was associated with ∼2.4 mm Hg decrease in diastolic BP ( P=0.001 ) . Physical activity was independently associated with lower BP in this sample of prepubertal children . The findings emphasize the importance of ensuring regular physical activity programs in primary schools to potentially reduce the risk of elevated BP in childhood and in later life Objective : This study aim ed to determine whether time spent outdoors was associated with objective ly measured physical activity , body mass index ( BMI ) z-score and overweight in elementary-school aged children , cross-sectionally and prospect ively over 3 years . Methods : Three-year cohort study with data collected during 2001 and 2004 . Nineteen r and omly selected state elementary schools across Melbourne , Australia . One hundred and eighty eight 5–6-year-old and 360 10–12-year-old children . Baseline parent reports of children 's time spent outdoors  during warmer and cooler months , on weekdays and weekends . At baseline and follow-up , children 's moderate and vigorous physical activity ( MVPA ) was objective ly assessed by accelerometry , and BMI z-score and overweight was calculated from measured height and weight . Results : Cross-sectionally , each additional hour outdoors on weekdays and weekend days during the cooler months was associated with an extra 27 min week−1 MVPA among older girls , and with an extra 20 min week−1 MVPA among older boys . Longitudinally , more time outdoors on weekends predicted higher MVPA on weekends among older girls and boys ( 5 min week−1 ) . The prevalence of overweight among older children at follow-up was 27–41 % lower among those spending more time outdoors at baseline . Conclusion : Encouraging 10–12-year-old children to spend more time outdoors may be an effective strategy for increasing physical activity and preventing increases in overweight and obesity . Intervention research investigating the effect of increasing time outdoors on children 's physical activity and overweight is warranted This study analyzed time-use interviews to report levels of active and inactive behavior  during the after-school period ( 3 - 6 pm ) . Interviews were conducted on r and om days from three separate seasons during third and fourth grade . Youth with at least two interviews during third ( 356 completed 2 interviews ; 506 completed 3 interviews [ 9 yrs ; 50 % boys ] ) and fourth ( 186 completed 2 interviews ; 768 completed 3 interviews [ 10 yrs ; 50 % boys ] ) grade were included to report levels of moderate-to-vigorous physical activity ( MVPA ) , light physical activity , inactive screen time  , inactive nonscreen time , and travel by location and who the activity was undertaken with .  Reporting time outside the home and with peers ( single or group ) was related to higher levels of MVPA . While inside the home , screen and nonscreen proportions were comparable ( 38 % and 40 % , respectively ) , despite unique patterns ( screen : boys > girls ; nonscreen : girls > boys ) . Reporting time with both parents was associated with more nonscreen time ; whereas reporting time with peer groups was associated with lower screen time . Underst and ing active and inactive patterns of children 's behavior outside of school hours can be very important in contributing toward the development of innovative interventions for increasing physical activity PURPOSE To evaluate an incentive-based intervention to increase time spent outdoors among children in a 9-month cluster r and omised controlled trial . METHODS Two hundred and eighty-five children aged 6 - 12 years of age were r and omised to the intervention ( n = 147 ) or control arm ( n = 138 ) in the Family incentive trial ( FIT ) . The FIT intervention comprised of targeted education on myopia and good eye care habits , structured weekend outdoor activities and incentives for children to increase their daily steps via pedometers . The main outcome measure was outdoor time , measured by the WHO question naire and a 1-week diary . RESULTS Interim analysis at 6 months showed a significant increase in mean outdoor time per week in the intervention arm ( 14.75 h week(-1 ) ) compared to the control arm ( 12.40 h week(-1 ) ) as measured by the question naire ( p = 0.04 ) . However , greater outdoor time was not statistically significant at the end of the trial ( 15.95 h week(-1 ) vs 14.34 h in the control group ( p = 0.29 ) . CONCLUSIONS There was an increase in outdoor time for children in the incentive-based physical activity outdoor program after 6 months but not at the end of the trial . Further larger school trials with better compliance with the intervention and longer duration could be conducted to evaluate clinical outcomes such as myopic shifts 
    Output:
    