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: OBJECTIVE To determine the television- , DVD- , and video-viewing habits of children younger than 2 years . DESIGN A telephone survey of 1009 parents of children aged 2 to 24 months . SETTING Parents in Minnesota and Washington state were surveyed . PARTICIPANTS A r and om sample of parents of children born in the previous 2 years was drawn from birth certificate records . Households in which English was not spoken were excluded , as were children with major disabilities . MAIN OUTCOME MEASURE The amount of regular television and DVD/video viewing by content , reasons for viewing , and frequency of parent-child coviewing . RESULTS By 3 months of age , about 40 % of children regularly watched  television , DVDs , or videos .  By 24 months , this proportion rose to 90 % . The median age at which regular media exposure was introduced was 9 months . Among those who watched , the average viewing time per day rose from 1 hour per day for children younger than 12 months to more than 1.5 hours per day by 24 months . Parents watched with their children more than half of the time . Parents gave education , entertainment , and babysitting as major reasons for media exposure in their children younger than 2 years . CONCLUSIONS Parents should be urged to make educated choices about their children 's media exposure . Parental hopes for the educational potential of television can be supported by encouraging those parents who are already allowing screen time to watch with their children IMPORTANCE Identifying associations between preschool-aged children 's electronic media use and their later well-being is essential to supporting positive long-term outcomes . OBJECTIVE To investigate possible dose-response associations of young children 's electronic media use with their later well-being . DESIGN , SETTING , AND PARTICIPANTS The IDEFICS ( Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants ) study is a prospect i ve cohort study with an intervention component . Data were collected at baseline from September 1 , 2007 , through June 30 , 2008 , and at follow-up from September 1 , 2009 , through May 31 , 2010 , in 8 European countries participating in the IDEFICS study . This investigation is based on 3604 children aged 2 to 6 years who participated in the longitudinal component of the IDEFICS study only and not in the intervention .  EXPOSURE Early childhood electronic media use . MAIN OUTCOMES AND MEASURES The following 6 indicators of well-being from 2 vali date d instruments were used as outcomes at follow-up : Peer problems and Emotional problems subscales from the Strengths and Difficulties Question naire and Emotional well-being , Self-esteem , Family functioning , and Social networks subscales from the KINDLR ( Question naire for Measuring Health-Related Quality of Life in Children and Adolescents-Revised Version ) . Each scale was dichotomized to identify those children at risk for poorer outcomes . Indicators of electronic media use ( weekday and weekend television and electronic game [e-game]/computer use ) from baseline were used as predictors . RESULTS Associations varied between boys and girls ; however , associations suggested that increased levels of electronic media use predicted poorer well-being outcomes . Television viewing on weekdays or weekends was more consistently associated with poorer outcomes than e-game/computer use . Across associations , the likelihood of adverse outcomes in children ranged from a 1.2- to 2.0-fold increase for emotional problems and poorer family functioning for each additional hour of television viewing or e-game/computer use depending on the outcome examined . CONCLUSIONS AND RELEVANCE Higher levels of early childhood electronic media use are associated with children being at risk for poorer outcomes with some indicators of well-being . Further research is required to identify potential mechanisms Background Previous research has suggested that television ( TV ) viewing may be associated with increased behavioral and emotional problems in children . However , there are few prospect i ve studies targeted for its association with outcomes of children under 3 years old . The purpose of this study was to exam the association between children ’s early TV exposure at ages 18 and 30 months and the behavioral and  emotional outcomes at age 30 months . Methods We analyzed data collected prospect ively in the Japan Children ’s Study .  TV exposure was assessed by mothers ’ report at infant ages of 18 and 30 months . The outcomes were assessed using the Strengths and Difficulties Question naire ( SDQ ) . Analysis of Covariance was used to estimate the effect of TV exposure on behavioral and emotional outcomes . Results The percentage of children who watched TV 4 hours or more per day was 29.4 % at age 18 months , 24.5 % at age 30 months , and 21 % at both ages . Hyperactivity – inattention at age 30 months was positively associated with TV exposure at age 18 months , whereas prosocial behavior was negatively associated with hours of exposure even after adjustment . However , there were no significant differences in SDQ subscales according to daily hours of TV viewing at age 30 months . Conclusions Daily TV exposure at age 18 months was associated with hyperactivity – inattention and prosocial behavior at age 30 months . However , the directly casual relation was not proved in the present study . Additional research considering the TV program content and exposure timing are needed to investigate the causal relation between TV viewing and behavioral outcome OBJECTIVE . To examine the extent to which  infant television viewing  is associated with language and visual motor skills at 3 years of age . MEASURES . We studied 872 children who were participants in Project Viva , a prospect i ve cohort . The design used was a longitudinal survey , and the setting was a multisite group practice in Massachusetts . At 6 months , 1 year , and 2 years , mothers reported the number of hours their children watched television in a 24-hour period , from which we derived a weighted average of daily television viewing . We used multivariable regression analyses to predict the independent associations of television viewing between birth and 2 years with Peabody Picture Vocabulary Test III and Wide-Range Assessment of Visual Motor Abilities scores at 3 years of age . RESULTS . Mean daily television viewing in infancy ( birth to 2 years ) was 1.2 ( SD : 0.9 ) hours , less than has been found in other studies of this age group . Mean Peabody Picture Vocabulary Test III score at age 3 was 104.8 ( SD : 14.2 ) ; mean st and ardized total Wide-Range Assessment of Visual Motor Abilities score at age 3 was 102.6 ( SD : 11.2 ) . After adjusting for maternal age , income , education , Peabody Picture Vocabulary Test III score , marital status , and parity , and child 's age , gender , birth weight for gestational age , breastfeeding duration , race/ethnicity , primary language , and average daily sleep duration , we found that each additional hour of television viewing in infancy was not associated with Peabody Picture Vocabulary Test III or total st and ardized Wide-Range Assessment of Visual Motor Abilities scores at age 3 . CONCLUSION . Television viewing in infancy does not seem to be associated with language or visual motor skills at 3 years of age Observational longitudinal research is particularly useful for assessing etiology and prognosis and for providing evidence for clinical decision making . However , there are no structured reporting requirements for studies of this design to assist authors , editors , and readers . The authors developed and tested a checklist of criteria related to threats to the internal and external validity of observational longitudinal studies . The checklist criteria concerned recruitment , data collection , biases , and data analysis and descriptive issues relevant to study rationale , study population , and generalizability . Two raters independently assessed 49 r and omly selected articles describing stroke research published from 1999 to 2003 in six journals : American Journal of Epidemiology , Journal of Epidemiology and Community Health , Stroke , Annals of Neurology , Archives of Physical Medicine and Rehabilitation , and American Journal of Physical Medicine and Rehabilitation . On average , 17 of the 33 checklist criteria were reported . Criteria describing the study design were better reported than those related to internal validity . No relation was found between study type ( etiologic or prognostic ) or word count and quality of reporting . A flow diagram for summarizing participant flow through a study was developed . Editors and authors should consider using a checklist and flow diagram when reporting on observational longitudinal research BACKGROUND Underst and ing the determinants of physical activity in children is critical for the treatment and prevention of childhood obesity . Social-cognitive theory has been used to underst and behavioral patterns in children . OBJECTIVES To explore the relationship between health beliefs , self-efficacy , social support , and sedentary activities and physical  activity levels in children and to examine the relationship between physical activity and  children 's  self-esteem . METHODS Ninety-two children aged 10 to 16 years completed the study .  Physical activity was monitored for 1 week with a motion detector ( Actitrac ; IM Systems , Baltimore , Md ) . Moderate-level activity and high-level activity were defined based on the results of treadmill testing . Health beliefs , self-efficacy , social influences , and time spent in sedentary behaviors were determined through question naires . Self-esteem was measured using the Piers-Harris Children 's Self-Concept Scale . Chronic anxiety was measured with the Revised Children 's Manifest Anxiety Scale . RESULTS There was a significant decline in physical activity levels between ages 10 and 16 years , particularly in girls . Preteen girls spent approximately 35 % more time in low- and high-level activity than did teenage girls ( P<.001 ) . Overall , children spent 75.5 % of the day inactive , with a mean + /- SD of 5.2 + /- 1.8 hours watching television , sitting at the computer , and doing homework . In contrast , only 1.4 % of the day ( 12.6 + /- 12.2 minutes ) was spent in vigorous activity . Time spent in sedentary behaviors was inversely correlated with the amount of moderate-level activity ( P<.001 ) but not high-level activity . In contrast , time spent in high-level activity correlated with self-efficacy scores ( P<.001 ) and social influences scores ( P<.005 ) . High-level physical activity was also associated with improved self-esteem ( P<.05 ) . Higher health beliefs scores were not correlated with physical activity levels . CONCLUSIONS Children and adolescents are largely sedentary . Correlates of high- and low-level physical activity are different . Time spent on sedentary activities is inversely correlated with moderate-level activity , while self-efficacy and social influences are positively correlated with more intense physical activity . In addition , increased high-level physical activity is an important component in the development of self-esteem in children OBJECTIVE : To assess the effectiveness of a  parent-focused intervention on  infants ’ obesity-risk behaviors and BMI . METHODS : This cluster r and omized controlled trial recruited 542 parents and their infants ( mean age 3.8 months at baseline ) from 62 first-time parent groups . Parents were offered six 2-hour dietitian-delivered sessions over 15 months focusing on parental knowledge , skills , and social support around infant feeding , diet , physical activity , and television viewing . Control group parents received 6 newsletters on nonobesity-focused themes ; all parents received usual care from child health nurses . The primary outcomes of interest were child diet ( 3 × 24-hour diet recalls ) , child physical activity ( accelerometry ) , and child TV viewing ( parent report ) . Secondary outcomes included BMI z-scores ( measured ) . Data were collected when children were 4 , 9 , and 20 months of age . RESULTS : Unadjusted analyses showed that , compared with controls , intervention group children consumed fewer grams of noncore drinks ( mean difference = –4.45 ; 95 % confidence interval [ CI ] : –7.92 to –0.99 ; P = .01 ) and were less likely to consume any noncore drinks ( odds ratio = 0.48 ; 95 % CI : 0.24 to 0.95 ; P = .034 ) midintervention ( mean age 9 months ) . At intervention conclusion ( mean age 19.8 months ) , intervention group children consumed fewer grams of sweet snacks ( mean difference = –3.69 ; 95 % CI : –6.41 to –0.96 ; P = .008 ) and viewed fewer daily minutes of television ( mean difference = –15.97 : 95 % CI : –25.97 to –5.96 ; P = .002 ) . There was little statistical evidence of differences in fruit , vegetable , savory snack , or water consumption or in BMI z-scores or physical activity . CONCLUSIONS : This intervention result ed in reductions in sweet snack consumption and television viewing in 20-month-old children OBJECTIVES To calibrate and vali date the ActiGraph GT3X+ to measure sedentary behaviour and physical activity in 2 - 3 year olds , using 5-s epochs ; and to compare the predictive validity of the result ing cut-points with that of NHANES ' , Trost 's , and Pate 's 15-s cut-points . DESIGN Cross-sectional study . METHODS Eighteen children ( 2.86 ± 0.60 years ) wore an ActiGraph GT3X+ during video-recorded semi-structured calibration activity sessions . Activity was coded following Children 's Activity Rating Scale . Receiver Operating Characteristic analysis was used to derive Axis1 and vector magnitude cut-points for sedentary behaviour and moderate-to-vigorous physical activity at 5-s epochs . Agreement with Children 's Activity Rating Scale was assessed with Cohen 's kappa , Lin 's concordance , and Bl and -Altman 
    Output:
    
agent
In conclusion , very little is known about sedentary behaviors other than screen time in this age group .
Although highly variable , findings suggest that children are already engaging in high levels of screen time by age 2 and the majority exceed current recommendations
***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: OBJECTIVE To determine the television- , DVD- , and video-viewing habits of children younger than 2 years . DESIGN A telephone survey of 1009 parents of children aged 2 to 24 months . SETTING Parents in Minnesota and Washington state were surveyed . PARTICIPANTS A r and om sample of parents of children born in the previous 2 years was drawn from birth certificate records . Households in which English was not spoken were excluded , as were children with major disabilities . MAIN OUTCOME MEASURE The amount of regular television and DVD/video viewing by content , reasons for viewing , and frequency of parent-child coviewing . RESULTS By 3 months of age , about 40 % of children regularly watched  television , DVDs , or videos .  By 24 months , this proportion rose to 90 % . The median age at which regular media exposure was introduced was 9 months . Among those who watched , the average viewing time per day rose from 1 hour per day for children younger than 12 months to more than 1.5 hours per day by 24 months . Parents watched with their children more than half of the time . Parents gave education , entertainment , and babysitting as major reasons for media exposure in their children younger than 2 years . CONCLUSIONS Parents should be urged to make educated choices about their children 's media exposure . Parental hopes for the educational potential of television can be supported by encouraging those parents who are already allowing screen time to watch with their children IMPORTANCE Identifying associations between preschool-aged children 's electronic media use and their later well-being is essential to supporting positive long-term outcomes . OBJECTIVE To investigate possible dose-response associations of young children 's electronic media use with their later well-being . DESIGN , SETTING , AND PARTICIPANTS The IDEFICS ( Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants ) study is a prospect i ve cohort study with an intervention component . Data were collected at baseline from September 1 , 2007 , through June 30 , 2008 , and at follow-up from September 1 , 2009 , through May 31 , 2010 , in 8 European countries participating in the IDEFICS study . This investigation is based on 3604 children aged 2 to 6 years who participated in the longitudinal component of the IDEFICS study only and not in the intervention .  EXPOSURE Early childhood electronic media use . MAIN OUTCOMES AND MEASURES The following 6 indicators of well-being from 2 vali date d instruments were used as outcomes at follow-up : Peer problems and Emotional problems subscales from the Strengths and Difficulties Question naire and Emotional well-being , Self-esteem , Family functioning , and Social networks subscales from the KINDLR ( Question naire for Measuring Health-Related Quality of Life in Children and Adolescents-Revised Version ) . Each scale was dichotomized to identify those children at risk for poorer outcomes . Indicators of electronic media use ( weekday and weekend television and electronic game [e-game]/computer use ) from baseline were used as predictors . RESULTS Associations varied between boys and girls ; however , associations suggested that increased levels of electronic media use predicted poorer well-being outcomes . Television viewing on weekdays or weekends was more consistently associated with poorer outcomes than e-game/computer use . Across associations , the likelihood of adverse outcomes in children ranged from a 1.2- to 2.0-fold increase for emotional problems and poorer family functioning for each additional hour of television viewing or e-game/computer use depending on the outcome examined . CONCLUSIONS AND RELEVANCE Higher levels of early childhood electronic media use are associated with children being at risk for poorer outcomes with some indicators of well-being . Further research is required to identify potential mechanisms Background Previous research has suggested that television ( TV ) viewing may be associated with increased behavioral and emotional problems in children . However , there are few prospect i ve studies targeted for its association with outcomes of children under 3 years old . The purpose of this study was to exam the association between children ’s early TV exposure at ages 18 and 30 months and the behavioral and  emotional outcomes at age 30 months . Methods We analyzed data collected prospect ively in the Japan Children ’s Study .  TV exposure was assessed by mothers ’ report at infant ages of 18 and 30 months . The outcomes were assessed using the Strengths and Difficulties Question naire ( SDQ ) . Analysis of Covariance was used to estimate the effect of TV exposure on behavioral and emotional outcomes . Results The percentage of children who watched TV 4 hours or more per day was 29.4 % at age 18 months , 24.5 % at age 30 months , and 21 % at both ages . Hyperactivity – inattention at age 30 months was positively associated with TV exposure at age 18 months , whereas prosocial behavior was negatively associated with hours of exposure even after adjustment . However , there were no significant differences in SDQ subscales according to daily hours of TV viewing at age 30 months . Conclusions Daily TV exposure at age 18 months was associated with hyperactivity – inattention and prosocial behavior at age 30 months . However , the directly casual relation was not proved in the present study . Additional research considering the TV program content and exposure timing are needed to investigate the causal relation between TV viewing and behavioral outcome OBJECTIVE . To examine the extent to which  infant television viewing  is associated with language and visual motor skills at 3 years of age . MEASURES . We studied 872 children who were participants in Project Viva , a prospect i ve cohort . The design used was a longitudinal survey , and the setting was a multisite group practice in Massachusetts . At 6 months , 1 year , and 2 years , mothers reported the number of hours their children watched television in a 24-hour period , from which we derived a weighted average of daily television viewing . We used multivariable regression analyses to predict the independent associations of television viewing between birth and 2 years with Peabody Picture Vocabulary Test III and Wide-Range Assessment of Visual Motor Abilities scores at 3 years of age . RESULTS . Mean daily television viewing in infancy ( birth to 2 years ) was 1.2 ( SD : 0.9 ) hours , less than has been found in other studies of this age group . Mean Peabody Picture Vocabulary Test III score at age 3 was 104.8 ( SD : 14.2 ) ; mean st and ardized total Wide-Range Assessment of Visual Motor Abilities score at age 3 was 102.6 ( SD : 11.2 ) . After adjusting for maternal age , income , education , Peabody Picture Vocabulary Test III score , marital status , and parity , and child 's age , gender , birth weight for gestational age , breastfeeding duration , race/ethnicity , primary language , and average daily sleep duration , we found that each additional hour of television viewing in infancy was not associated with Peabody Picture Vocabulary Test III or total st and ardized Wide-Range Assessment of Visual Motor Abilities scores at age 3 . CONCLUSION . Television viewing in infancy does not seem to be associated with language or visual motor skills at 3 years of age Observational longitudinal research is particularly useful for assessing etiology and prognosis and for providing evidence for clinical decision making . However , there are no structured reporting requirements for studies of this design to assist authors , editors , and readers . The authors developed and tested a checklist of criteria related to threats to the internal and external validity of observational longitudinal studies . The checklist criteria concerned recruitment , data collection , biases , and data analysis and descriptive issues relevant to study rationale , study population , and generalizability . Two raters independently assessed 49 r and omly selected articles describing stroke research published from 1999 to 2003 in six journals : American Journal of Epidemiology , Journal of Epidemiology and Community Health , Stroke , Annals of Neurology , Archives of Physical Medicine and Rehabilitation , and American Journal of Physical Medicine and Rehabilitation . On average , 17 of the 33 checklist criteria were reported . Criteria describing the study design were better reported than those related to internal validity . No relation was found between study type ( etiologic or prognostic ) or word count and quality of reporting . A flow diagram for summarizing participant flow through a study was developed . Editors and authors should consider using a checklist and flow diagram when reporting on observational longitudinal research BACKGROUND Underst and ing the determinants of physical activity in children is critical for the treatment and prevention of childhood obesity . Social-cognitive theory has been used to underst and behavioral patterns in children . OBJECTIVES To explore the relationship between health beliefs , self-efficacy , social support , and sedentary activities and physical  activity levels in children and to examine the relationship between physical activity and  children 's  self-esteem . METHODS Ninety-two children aged 10 to 16 years completed the study .  Physical activity was monitored for 1 week with a motion detector ( Actitrac ; IM Systems , Baltimore , Md ) . Moderate-level activity and high-level activity were defined based on the results of treadmill testing . Health beliefs , self-efficacy , social influences , and time spent in sedentary behaviors were determined through question naires . Self-esteem was measured using the Piers-Harris Children 's Self-Concept Scale . Chronic anxiety was measured with the Revised Children 's Manifest Anxiety Scale . RESULTS There was a significant decline in physical activity levels between ages 10 and 16 years , particularly in girls . Preteen girls spent approximately 35 % more time in low- and high-level activity than did teenage girls ( P<.001 ) . Overall , children spent 75.5 % of the day inactive , with a mean + /- SD of 5.2 + /- 1.8 hours watching television , sitting at the computer , and doing homework . In contrast , only 1.4 % of the day ( 12.6 + /- 12.2 minutes ) was spent in vigorous activity . Time spent in sedentary behaviors was inversely correlated with the amount of moderate-level activity ( P<.001 ) but not high-level activity . In contrast , time spent in high-level activity correlated with self-efficacy scores ( P<.001 ) and social influences scores ( P<.005 ) . High-level physical activity was also associated with improved self-esteem ( P<.05 ) . Higher health beliefs scores were not correlated with physical activity levels . CONCLUSIONS Children and adolescents are largely sedentary . Correlates of high- and low-level physical activity are different . Time spent on sedentary activities is inversely correlated with moderate-level activity , while self-efficacy and social influences are positively correlated with more intense physical activity . In addition , increased high-level physical activity is an important component in the development of self-esteem in children OBJECTIVE : To assess the effectiveness of a  parent-focused intervention on  infants ’ obesity-risk behaviors and BMI . METHODS : This cluster r and omized controlled trial recruited 542 parents and their infants ( mean age 3.8 months at baseline ) from 62 first-time parent groups . Parents were offered six 2-hour dietitian-delivered sessions over 15 months focusing on parental knowledge , skills , and social support around infant feeding , diet , physical activity , and television viewing . Control group parents received 6 newsletters on nonobesity-focused themes ; all parents received usual care from child health nurses . The primary outcomes of interest were child diet ( 3 × 24-hour diet recalls ) , child physical activity ( accelerometry ) , and child TV viewing ( parent report ) . Secondary outcomes included BMI z-scores ( measured ) . Data were collected when children were 4 , 9 , and 20 months of age . RESULTS : Unadjusted analyses showed that , compared with controls , intervention group children consumed fewer grams of noncore drinks ( mean difference = –4.45 ; 95 % confidence interval [ CI ] : –7.92 to –0.99 ; P = .01 ) and were less likely to consume any noncore drinks ( odds ratio = 0.48 ; 95 % CI : 0.24 to 0.95 ; P = .034 ) midintervention ( mean age 9 months ) . At intervention conclusion ( mean age 19.8 months ) , intervention group children consumed fewer grams of sweet snacks ( mean difference = –3.69 ; 95 % CI : –6.41 to –0.96 ; P = .008 ) and viewed fewer daily minutes of television ( mean difference = –15.97 : 95 % CI : –25.97 to –5.96 ; P = .002 ) . There was little statistical evidence of differences in fruit , vegetable , savory snack , or water consumption or in BMI z-scores or physical activity . CONCLUSIONS : This intervention result ed in reductions in sweet snack consumption and television viewing in 20-month-old children OBJECTIVES To calibrate and vali date the ActiGraph GT3X+ to measure sedentary behaviour and physical activity in 2 - 3 year olds , using 5-s epochs ; and to compare the predictive validity of the result ing cut-points with that of NHANES ' , Trost 's , and Pate 's 15-s cut-points . DESIGN Cross-sectional study . METHODS Eighteen children ( 2.86 ± 0.60 years ) wore an ActiGraph GT3X+ during video-recorded semi-structured calibration activity sessions . Activity was coded following Children 's Activity Rating Scale . Receiver Operating Characteristic analysis was used to derive Axis1 and vector magnitude cut-points for sedentary behaviour and moderate-to-vigorous physical activity at 5-s epochs . Agreement with Children 's Activity Rating Scale was assessed with Cohen 's kappa , Lin 's concordance , and Bl and -Altman 
    Output:
    