Validation and application of a novel method of measuring non-response bias in school-based surveys of paediatric overweight and obesity.

OBJECTIVE: To validate a method of estimating non-response bias to a school-based survey based on body mass index (BMI). METHODS: A population survey of Australian students in Kindergarten and Grades 2, 4, 6, 8 and 10 (N=5 407) was conducted in 2004, and height and weight measured. Teachers matched the height and weight of all students who were selected to participate, but who were not measured (non-participating students) and of half of the students whose height and weight had been measured based on comparisons with the remaining half of measured students. Among those students whose height and weight had been both measured and estimated based on matching with the most similar student, percent agreement between the BMI categories based on measured and estimated values was calculated to determine the validity of the estimated BMI value. The prevalence of overweight and obesity among participating and non-participating students was compared to determine the magnitude of non-response bias. RESULTS: For more than 88% of classes, percent agreement between BMI categories based on estimated and measured height and weight was >60%. The differences in the prevalence of overweight and obesity between participating and non-participating students were all less than one percentage point. CONCLUSIONS: Most teachers were able to validly match students based on their height and weight, allowing estimation of and adjustment for non-response bias among non-participating students.

Changes in cardiorespiratory fitness among children and adolescents in Australia: 1997 and 2004.

In this paper, we describe changes in cardiorespiratory fitness among children and adolescents in New South Wales, Australia from 1997 to 2004. Altogether, 4363 children and adolescents were surveyed in 1997 and 3720 were surveyed in 2004. Participants were randomly selected from Grades 4 and 6 in primary school and Grades 8 and 10 in high schools. Cardiorespiratory fitness was assessed on both occasions using the 20-m shuttle run test. There was a very small, but statistically significant, increase in the median number of laps completed for primary (P = 0.02) and high school girls (P = 0.02) and high school boys (P = 0.01); however, the prevalence of adequate cardiorespiratory fitness did not change significantly from 1997 to 2004 for primary or high school boys or girls. Cardiorespiratory fitness was higher among the most socially advantaged boys and girls and this tertile also recorded the greatest increases in all but one group. Over the period 1997 to 2004, the prevalence of adequate cardiorespiratory fitness among students rose slightly in general. It is concerning that the gap between low and high socio-economic tertiles appears to have widened.

Costs of managing conditions associated with obesity among Australian teenagers.

AIM: To determine the health-care charges associated with monitoring and managing, over 1 year, the cases of elevated insulin concentration, elevated alanine aminotransferase concentration and dyslipidaemia due to overweight or obesity among 15-19-year-old Australian males and females. METHODS: Fasting blood samples (n= 500) were collected in 2004 from a representative population sample of adolescents (n= 496; mean age 15.3 years) attending schools in Sydney, Australia. Full service charges and Medicare expenditures for specialist medical and dietary consultations, pathology tests and radiological investigations, over 1 year, under efficient and inefficient health-care delivery models, including and excluding participants in the healthy body mass index (BMI) category. RESULTS: Under an inefficient delivery model and including all participants with elevated risk factors, the Medicare expenditure was $A305.1 million per annum (M pa). Exclusion of participants in the healthy BMI category resulted in an annual Medicare expenditure of $A170.0M pa. Under an efficient delivery model and including all participants with elevated risk factors, the Medicare expenditure was $A295.5M pa. Exclusion of participants in the healthy BMI category reduced annual Medicare expenditure to $A164.8M pa. Medicare expenditure for 15-19-year-olds would increase by 48% if only cases among overweight and obese adolescents were treated and by 85% if all cases were identified and treated. CONCLUSIONS: Short-term management of the health consequences of overweight and obesity among adolescents will increase Medicare expenditure on this group by at least 48%. Failure to treat will delay, but compound, health-care expenditure.

Parents of school students on childhood overweight: the Weight of Opinion Study.

AIM: The perceptions of parents of school-aged children regarding child and adolescent overweight and obesity were examined. METHOD: Parents with children in primary and secondary schools in socio-economically diverse areas across metropolitan Sydney and rural New South Wales, Australia, were recruited for focus group discussions. Content analysis was used to analyse the focus group transcripts. RESULTS: Participants were concerned about overweight among school-aged children and young people, but were reluctant to address it with their own children. The parents wanted general practitioners to raise the issue, but not other professionals or friends/relations. The participants agreed that schools had an educational role to play in both healthy eating and physical activity, but disagreed about whether schools should regulate foods brought from home or supplied at school. Parents suggested various ways of restricting marketing to children, educating parents and children, increasing opportunities for physical activity and increasing access to healthier foods. CONCLUSIONS: Parents are concerned about overweight among children and adolescents, but are reluctant to take action, and would find it difficult to be effective change agents. There are opportunities for intervention, but they must recognise the salient emotional issues associated with weight and food among parents.

Sedentariness, small-screen recreation, and fitness in youth.

BACKGROUND: There are concerns that sedentariness among young people has increased and that this may be detrimental to their health. The purpose of this study was to examine the association between sedentary activities, including small-screen recreation (SSR: watching TV/DVDs/videos, recreational computer use) and cardiorespiratory endurance (CRE) in children aged 11-15 years. METHODS: A cross-sectional representative population survey was taken of New South Wales (Australia) school students in Grades 6, 8, and 10 (N=2750) in 2004. Sedentary activities and SSR were measured by a self-report questionnaire. CRE was determined by the 20-meter multi-stage shuttle run test. The optimal cut point for time spent on SSR was determined by receiver operating characteristic analysis. RESULTS: Time spent in sedentary activities was inversely associated with CRE among Grade 8 students (p=0.01) and Grade 10 girls (p=0.03). CRE was lower among Grade 8 students (p<0.001) and Grade 10 girls (p<0.001) who spent >or=2 hours/day on SSR compared with students who spent <2 hours/day. The 2-hour/day cut point for SSR had high sensitivity (boys: 84%, [95% CI=79%, 87%]; girls: 79% [95% CI=74%, 84%]) and low specificity (boys: 28% [95% CI=24%, 32%]; girls: 42% [95% CI=38%, 46%]). CONCLUSIONS: Cardiorespiratory endurance did not differ consistently across quintiles of sedentariness and SSR among boys; however, among girls there was a consistent inverse association. If confirmed in prospective studies, these findings have important implications for risk of chronic disease.

Encounters between adolescents and general practice in Australia.

AIM: To describe the nature of the encounters between adolescents and general practice in Australia. METHODS: Data collected by the Bettering the Evaluation and Care of Health programme from 1998-2004 were analysed. Data for 10-14-year-old and 15-19-year-old males and females were compared with data for 25-29-year-olds. The outcome measures included: number of encounters compared with other age groups, reasons for encounter, problems managed, treatments prescribed and referrals made for key problems and types of consultations. RESULTS: Adolescents have the lowest rate of encounter with general practice, compared with all other age groups. Respiratory, skin, musculoskeletal and unspecified (fever, injury, weakness) problems accounted for the great majority of reasons for encounter and problems managed. Management of mental health problems, preventive health care and health education were very infrequently managed problems. Standard surgery consultations were more common among adolescents than among young adults. CONCLUSIONS: Adolescents have a relatively low rate of encounter with general practice and the problems managed are primarily physical ailments. There is great scope to improve delivery of preventive health care and to increase management of mental health problems.

The population prevalence of adverse concentrations and associations with adiposity of liver tests among Australian adolescents.

AIM: Paediatric overweight has a high incidence and has serious consequences for health, including non-alcoholic fatty liver disease (NAFLD). However, very little is known about NAFLD among young people, particularly from a population perspective. This paper reports the prevalence of elevated concentrations of four liver enzymes and their associations with adiposity in a representative population sample of Australian adolescents. METHODS: Overnight fasting blood samples were collected from a representative population sample of 500 Grade 10 students (15-years-old) attending schools in Sydney, Australia, between February and May, 2004. Weight, height and waist girth were measured. The prevalence of adverse concentrations of the enzymes alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were described for all boys and girls and by body mass index (BMI) categories. The nature of the associations between the enzyme concentrations and indices of adiposity were characterised, and regression equations for estimating enzyme concentrations from BMI were prepared. RESULTS: The prevalence of adverse concentrations of ALT (most likely as a result of NAFLD) and GGT were approximately 10%, while the prevalence of adverse concentrations of AST and ALP were approximately 7% and 5% respectively. The prevalence of adverse concentrations of ALT, GGT and AST increased across BMI categories, while the prevalence of adverse concentrations of ALP declined across BMI categories. CONCLUSIONS: The high prevalence of NAFLD in a population sample of healthy Australian adolescents represents a significant burden of disease.

Physical activity among adolescents in New South Wales (Australia): 1997 and 2004.

PURPOSE: To examine secular trends, seasonal and socioeconomic differences in physical activity participation among Australian adolescents in 1997 and 2004. METHODS: Repeat cross-sectional school survey, conducted in 1997 and 2004. School students were randomly selected from grades 8 and 10 in New South Wales Australia (1997, N = 2026; 2004 N = 1771). Time spent in moderate-to-vigorous physical activity (MVPA) was assessed by self-reported participation in organized and nonorganized physical activity separately for summer and winter by sex, grade, and socioeconomic status (SES). RESULTS: Between survey periods, the proportion of students reporting > or = 60 min.d(-1) of MVPA increased, except among grade 10 boys during winter. MVPA (min.d(-1)) increased among all groups during summer school terms, during winter school terms, MVPA was relatively stable between surveys for grade 8 students but inconsistent among grade 10 students. Organized MVPA increased among all groups in both summer (19-49 min.d(-1)) and winter (7-21 min.d(-1)) school terms. Participation in nonorganized MVPA increased only during summer school terms (4-32 min.d(-1)) and decreased during winter school terms (7-17 min.d(-1)). MVPA increased consistently among students in the high-SES group compared with other SES groups, independent of season, and in some cases MVPA decreased in low-SES groups during winter school terms. CONCLUSION: Overall, the patterns of change were similar for boys and girls, with substantial increases in summer school terms and insubstantial changes during winter school terms (with the exception of a decrease among grade 10 boys). There was a direct association between change in participation in MVPA and SES, indicating that interventions are required to focus on the needs of less-advantaged students.

Changes in physical activity participation from 1985 to 2004 in a statewide survey of Australian adolescents.

OBJECTIVE: To examine changes in physical activity during a 19-year period between 2 representative cohorts of adolescents from New South Wales, Australia. DESIGN: Repeat cross-sectional study. SETTING: Randomly selected secondary schools from New South Wales, the most populous state in Australia. PARTICIPANTS: One thousand fifty-five adolescents surveyed in May through October 1985 (with the Australian Health and Fitness Survey) and 1226 adolescents surveyed in March through April 2004 (with the New South Wales Schools Physical Activity and Nutrition Survey). Participants were aged 12 to 15 years. MAIN OUTCOME MEASURES: The proportion meeting current guidelines for physical activity (60 min/d of moderate to vigorous physical activity) and time spent in moderate to vigorous physical activity assessed by self-reported participation in physical activity using the same questionnaire at both time points. RESULTS: All of the age and sex groups reported increases in both the prevalence of physical activity (mean increase range, 11.7%-20.0%) and in the minutes per week spent in moderate to vigorous physical activity (median increase range, 135-175 minutes). These findings remained the same after additional adjustment for age, socioeconomic status, and cultural background. CONCLUSIONS: Physical activity participation has considerably increased during the past 19 years among adolescents in the state of New South Wales, Australia. These findings provide important information about trends in compliance with physical activity recommendations and in time spent in physical activity. They could help to explain what aspects may need to be promoted to maximize the role of physical activity in reducing the high and increasing rates of child and adolescent obesity.

Perceptions of adolescents on overweight and obesity: the weight of opinion study.

AIM: The incidence and prevalence of overweight and obesity are rising around the world. Health promotion planning must be informed by the knowledge, perceptions, motivations and perceived needs of the target population, but little is known about how adolescents perceive overweight and obesity, its causes and solutions. METHODS: A cross-sectional, non-representative sample of 12- to 17-year-old boys and girls (n = 58) attending schools in diverse metropolitan areas and one rural area in NSW, Australia. Focus groups were conducted in 2005 and content analysis was used to identify key themes. RESULTS: The students were aware that overweight was becoming increasingly common. They perceived the negative consequences primarily in psycho-social terms, but were also aware of the long-term physical health consequences. Behaviours, appearance, motivation and self-esteem were used as criteria to judge if a person was overweight and the students distinguished between 'healthy' and 'ideal' (physically attractive) weight. The major barriers to maintaining a healthy weight were home, school and community environments in which fatty/high sugar foods were too easily accessible and where opportunities for participating in physical activity were sometimes limited. Student-identified strategies to address the issue encompassed government policy, advertising and media, schools and home. CONCLUSIONS: The students have a mature and complex understanding of overweight and its potential solutions, making them likely to be creative contributors and responsive to wide-ranging, multi-component interventions.

Mothers of pre-school children talk about childhood overweight and obesity: The Weight Of Opinion Study.

AIM: To investigate the perceptions of parents of young children aged 2-5 years regarding childhood overweight and obesity. METHODS: Parents with children in seven pre-schools and long day-care centres from diverse socio-economic areas across metropolitan Sydney and one rural area were recruited for focus groups. Focus group transcripts were analysed using content analysis. RESULTS: Providing food was an emotional issue for the mothers in this study. They were more concerned about their young children being underweight than overweight, and this increased their stress around children's eating. Food treats were perceived as entitlements. Mothers did believe that they were responsible for their children's eating, but acknowledged the influence of other environmental factors related to food retail and marketing. Practical and safety issues limited opportunities for their children to be physically active beyond the formal child-care setting. Parents had practical suggestions for solutions to some of the barriers they experienced, and wanted support for their role. CONCLUSIONS: The emotional intensity of the mothers' perceptions about their children's eating and weight status suggests that interventions, including communications, need to go beyond information and engage with parents' emotions. Some food concerns were actually related to broader parenting issues and indicate the potential value for interventions to focus on behavioural parenting techniques. Preventive interventions need to acknowledge the issues faced by parents and support their role directly, such as through making healthy and active behaviours easily available, and indirectly, through providing local services, including early childhood services.

Characteristics of travel to and from school among adolescents in NSW, Australia.

AIM: Active transport to and from school is frequently identified as an opportunity to increase energy expenditure among young people. The epidemiology of travel behaviours among Grade 6, 8 and 10 students in NSW is reported. METHODS: A representative population survey of students in NSW, Australia was conducted during February to May 2004 (n = 2750) and the prevalence of travelling to and from school by walking, car and public transport was determined for Grade 6, 8 and 10 students. RESULTS: Among Grade 6 students, approximately 30% travelled by car, 30% walked and 20% used public transport to travel to school (the travel habits of 20% could not be accurately characterised). Among secondary school students, approximately 50% used public transport, 15-20% travelled by car and 15-20% walked. Among those who walked or used public transport, the median times spent walking were 10-15 min and 5 min per trip, respectively. CONCLUSIONS: While there is little scope to increase the prevalence of active transport among secondary school students, there is potential to do so among primary school students. Primary school students who replace travelling to and from school by car with walking will experience an increase in activity energy expenditure of up to 10% and those who change to public transport will experience an increase in activity energy expenditure of up to 3%.

Promoting physical activity participation among children and adolescents.

With global increases in the prevalence of overweight and obesity among children and adolescents, there has never been a more urgent need for effective physical activity programs. The aim of this narrative review is to summarize the evidence of the effectiveness of interventions that report physical activity outcomes in children aged 4-12 years and adolescents aged 13-19 years. A systematic search of electronic databases identified 76 interventions. Most interventions were delivered via the school setting (57 interventions), nine through the family setting, six via primary care, and four in community- or Internet-based settings. Children's physical activity interventions that were most effective in the school setting included some focus on physical education, activity breaks, and family strategies. Interventions delivered in the family setting were not highly effective, but many were pilot studies. The use of motivationally tailored strategies and program delivery in the primary care setting showed promise among adolescents. Many studies had methodological and reporting flaws (e.g., no baseline data, poor study design, physical activity measures of unknown reliability and validity, and poor reporting of sample size, response rates, attrition/retention, compliance, year of intervention, and duration of intervention). Publications reporting the results of evaluations of intervention studies should follow the Consolidated Standards of Reporting Trials guidelines or, for nonrandomized studies, should follow the Transparent Reporting of Evaluations with Nonrandomized Designs guidelines. Further evidence of the effectiveness of interventions promoting young people's physical activity in family and community settings is needed.

Trends in the prevalence of overweight and obesity among young Australians, 1985, 1997, and 2004.

OBJECTIVE: To determine secular trends in overweight/obesity among 7- to 15-year-olds for the periods 1985, 1997, and 2004. RESEARCH METHOD AND PROCEDURES: Data from representative surveys conducted in New South Wales, Australia, in 1985, 1997, and 2004 were analyzed. Height and weight were measured, and BMI categories were created using International Obesity Task Force definitions. Students were grouped as Grades 2 + 4 + 6 and 8 + 10. RESULTS: The prevalences of overweight/obesity for 1985, 1997, and 2004 were 10.9%, 20.6%, and 25.7% among the younger boys and 10.6%, 19.5%, and 26.1% among the older boys. The average annual rate of increase for 1985 to 1997 was 0.81% and for 1997 to 2004 was 0.73% among the younger boys and was 0.74% and 0.94% for the two periods among the older boys. The prevalences of overweight/obesity in 1985, 1997, and 2004 were 14.0%, 22.0%, and 24.8% among the younger girls and 8.3%, 17.9%, and 19.8% among the older girls, respectively. The average annual rates of increase for the two periods were 0.8% and 0.4% among the younger girls and 0.80% and 0.27% among the older girls. Change in the prevalence of overweight/obesity and socioeconomic status were not associated. DISCUSSION: Over the period 1985 to 1997, the prevalence of overweight and obesity increased significantly among the younger and older boys and the younger girls. The prevalence of overweight, but not obesity, increased among the older girls over this period. Over the period 1997 to 2004, the prevalence of overweight/obesity combined increased significantly among boys of both age groups but not among girls.

The reliability of the Adolescent Sedentary Activity Questionnaire (ASAQ).

OBJECTIVE: To determine the test-retest reliability of a self-report questionnaire (the Adolescent Sedentary Activities Questionnaire; ASAQ) which assesses the time spent in a comprehensive range of sedentary activities, among school-aged young people. METHOD: Two-hundred and fifty school students aged 11-15 years from four primary and four high schools in metropolitan Sydney (New South Wales, Australia) completed the questionnaire under the same conditions on two occasions, 2 weeks apart during Autumn, 2002. RESULTS: Test-retest correlations for time total spent in sedentary behavior were >or=0.70, except for Grade 6 boys (Intraclass correlation coefficient (ICC)=0.57, 95%CI: 0.25, 0.76). Repeatability was generally higher on week days compared with week end days. ICC values for travel and social activities tended to be lower than for the other categories of sedentary behavior. There was little difference in the reliability across age groups. CONCLUSIONS: ASAQ has good to excellent reliability in the measurement of a broad range of sedentary behaviors among young people. ASAQ has good face validity, but further validity testing is required to provide a complete assessment of the instrument.

Australian GPs' perceptions about child and adolescent overweight and obesity: the Weight of Opinion study.

BACKGROUND: GPs can potentially play a significant role in assessing weight status, providing advice, and making referrals to address overweight and obesity and its consequences among children and adolescents. AIM: To investigate the perceptions of GPs about overweight and obesity in children and adolescents, including the extent to which they perceive it as a concern, the factors they see as causal, what actions they consider might be needed, and their sense of responsibility and self-efficacy. DESIGN OF STUDY: A cross-sectional qualitative study of GPs' perceptions. SETTING: General practice and primary health care services in the state of New South Wales, Australia. METHOD: Focus groups using a structured protocol were conducted with samples of GPs. Groups comprised a mix of male and female GPs from a range of cultural backgrounds and working in practices in low, medium and high socioeconomic areas. Data were recorded and transcribed. Content analysis was used to identify key themes. RESULTS: Many GPs are concerned about the increasing prevalence of childhood overweight and obesity. They are committed to dealing with the medical consequences, but are aware of the broad range of social causes. GPs perceived that parents are sensitive about this topic, making it difficult for them to raise the issue directly in clinical practice, unless they use lateral strategies. GPs were confident about providing advice, with some managing the problem independently, while others preferred to refer to specialised services. GPs perceived that there were significant barriers to patient compliance with advice. CONCLUSION: Whereas some GPs manage patients' lifestyle change directly, including children's weight management, others prefer to refer. Programmes, service delivery systems, and resources to support both approaches are required.

Changes in sedentary behavior among adolescent girls: a 2.5-year prospective cohort study.

PURPOSE: To describe longitudinal changes in leisure-time sedentary behavior among girls, during early to mid-adolescence. METHODS: A 2.5-year prospective cohort study, comprising 5 data collections, 6 months apart, between 2000 and 2002. Girls aged 12-15 years (n = 200) from 8 high schools located in Sydney, Australia, self-reported the usual time spent each week in a comprehensive range of sedentary behaviors. RESULTS: Retention rate for the study was 82%. Girls aged 12.8 years spent approximately 45% of their discretionary time in sedentary behavior, which increased to 63% at age 14.9 years. Watching TV, videos, and playing video games (small screen recreation; SSR) was the most popular sedentary pastime, accounting for 33% of time spent in sedentariness, followed by homework and reading (25%). Sedentary behavior increased 1.4 and 3.3 hours on week and weekend days, respectively. On weekdays, increased time was spent on hobbies (27 min/day) and on weekend days, increased time was spent sitting around talking with friends (60 min/day), computer use (37 min/day), and television viewing (34 min/day). CONCLUSIONS: Among girls, the transition between early and mid-adolescence was accompanied by a significant increase in leisure-time sedentary behavior. Interventions to reduce sedentariness among adolescent girls are best to focus on weekend behaviors. Studies seeking to examine the association between inactivity and the development of chronic health problems need to examine a diverse range of activities that comprehensively measure sedentariness. This information will provide a better understanding of inactivity patterns among adolescent girls.

Descriptive epidemiology of small screen recreation among Australian adolescents.

AIM: To describe the epidemiology of small screen recreation (SSR) that is: television, computer, video, and DVD use among school students aged 11-15 years in New South Wales, Australia. METHODS: Cross-sectional representative population survey (n=2750) of 45 primary and 48 secondary schools in rural and urban areas. Self-reported time spent in SSR was categorised according to national guidelines into less than 2 h per day (low users) or 2 or more hours per day (high users). RESULTS: Of primary and secondary school students, 53% and 72%, respectively, were high users of SSR. Boys spent significantly more time in SSR and were more likely to be high users of SSR compared with girls. For primary students, rural boys had a higher prevalence of high SSR use than urban boys (odds ratio (OR) 1.9, 95% confidence interval (CI) 1.0-3.5), while overweight girls had a higher prevalence than healthy-weight girls (OR 1.8, 95% CI 1.2-2.8). For secondary students, rural boys had a lower prevalence of high SSR use than urban boys (OR 0.5, 95% CI 0.3-0.6), and girls from high SES backgrounds had a lower prevalence than girls from low socio-economic status backgrounds (OR 0.6, 95% CI 0.3-1.0). CONCLUSION: The majority of school students in New South Wales exceed the national guidelines for SSR. Reducing the time spent in SSR among young people is one potential approach to increasing energy expenditure and reducing adiposity or maintaining a healthy weight. First steps for intervention strategies among school-age children to reduce SSR could include teaching awareness skills and self-monitoring techniques.

Sedentary behaviours among Australian adolescents.

OBJECTIVE: To describe the prevalence and distribution (by demographic characteristics and body mass index [BMI] category) of sedentary behaviour among Australian adolescents aged 11-15 years. METHOD: Cross-sectional representative population survey of school students (n = 2,750) in New South Wales, conducted in 2004. Students' self-reported time spent during a usual week in five categories of sedentary behaviour (small screen recreation [SSR], education, cultural, social and non-active travel). Height and weight were measured. RESULTS: Grade 6, 8 and 10 students spent approximately 34 hours, 41 hours and 45 hours/week of their discretionary time, respectively, engaged in sedentary behaviour. Urban students and students from Asian-speaking backgrounds spent significantly more time sedentary than students from rural areas or other cultural backgrounds. SSR accounted for 60% and 54% of sedentary behaviour among primary and high school students, respectively. Overweight and obese students spent more time in SSR than healthy weight students. Out-of-school hours educational activities accounted for approximately 20% of sedentary behaviour and increased with age. Girls spent twice the time in social activities compared with boys. Time spent in cultural activities declined with age. CONCLUSION: Sedentary behaviours among young people differ according to sex, age and cultural background. At least half of all time spent in sedentary behaviours was spent engaged in SSR. BMI was significantly associated with sedentary behaviour among some children, but not consistently across age groups. IMPLICATIONS: A clear understanding of young people's patterns of sedentary behaviour is required to develop effective and sustainable intervention programs to promote healthy living.

Promoting physical activity in Australian general practices: a randomised trial of health promotion advice versus hypertension management.

A randomised controlled trial was conducted to determine if physicians' advice to promote physical activity to patients was more effective if the advice was tailored to the management of hypertension, compared with more general health promotion advice. Participants included inactive 40- to 70-year-old patients visiting the physicians' during study recruitment period. Physicians provided verbal physical activity advice and written materials, both tailored to either general health promotion messages or specifically as a means for treating or managing hypertension. Seventy-five physicians and 98% (767/780) of screened eligible patients participated in the study. Differences between intervention and control groups self-reported physical activity were assessed over 6 months. Follow-up response rates were 92 and 84% at the 2- and 6-month assessments. There were no consistent, significant differences between groups at the 2- or 6-month assessments. Thus, neither intervention strategy resulted in significant changes in patients self-reported physical activity, regardless of the whether the advice was tailored to hypertension management or general health promotion advice.