***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 Physical activity promotion is a priority , but contribution of physicians ' interventions is unclear . The effectiveness of the PEPAF ( " Experimental Program for Physical Activity Promotion " ) , which was implemented exclusively by physicians in routine primary care from October 2003 to December 2004 , was assessed . METHODS Fifty-six Spanish family physicians were r and omized to either the intervention ( n = 29 ) or st and ard care ( n = 27 ) arm of the trial . The physicians recruited 4317 physically inactive patients ( 2248 for intervention and 2069 for control protocol s ) from a systematic sample after assessing their physical activity in routine practice . Intervention physicians provided advice to all patients and a physical activity prescription to the subgroup attending an additional appointment ( 30 % ) . The main outcome measure was the change in physical activity measured by blinded nurses using the 7-Day Physical Activity Recall . Secondary outcomes included cardiorespiratory fitness and health-related quality of life . RESULTS At 6 months , intervention patients increased physical activity more than controls ( adjusted difference , 18 min/wk [ 95 % confidence interval , 6 - 31 min/wk ] ; metabolic equivalent tasks x hours per week , 1.3 [ 95 % CI , 0.4 - 2.2 ] ) . The proportion of the population achieving minimal physical activity recommendations was 3.9 % higher in the intervention group ( 1.2%-6.9 % ; number needed to treat , 26 ) . No differences were found in secondary outcomes . The effect of intervention was positively modified in subjects older than 50 years ( P < or = .01 ) and in the prescription subgroup ( P < .001 ) . CONCLUSIONS Family physicians were effective for increasing physical activity of primary care patients . Overall clinical effect was small but relevant for population public health . Within the intervention program , clinical ly relevant effects were seen in patients receiving a physical activity prescription . Trial Registration clinical trials.gov Identifier : NCT00131079 Background A recent HTA review concluded that there was a need for RCTs of exercise referral schemes ( ERS ) for people with a medical diagnosis who might benefit from exercise .  Overall , there is still uncertainty as to the cost-effectiveness of ERS . Evaluation of public health interventions places challenges on conventional health economics approaches . This economic evaluation of a national public health intervention addresses this issue of where ERS may be most cost effective through subgroup analysis , particularly important at a time of financial constraint . Method This economic analysis included 798 individuals aged 16 and over ( 55 % of the r and omised controlled trial ( RCT ) sample ) with coronary heart disease risk factors and /or mild to moderate anxiety , depression or stress . Individuals were referred by health professionals in a primary care setting to a 16 week national exercise referral scheme ( NERS ) delivered by qualified exercise professionals in local leisure centres in Wales , UK . Health-related quality of life , health care services use , costs per participant in NERS , and willingness to pay for NERS were measured at 6 and 12 months . Results The base case analysis assumed a participation cost of £ 385 per person per year , with a mean difference in QALYs between the two groups of 0.027 . The incremental cost-effectiveness ratio was £ 12,111 per QALY gained . Probabilistic sensitivity analysis demonstrated an 89 % probability of NERS being cost-effective at a payer threshold of £ 30,000 per QALY . When participant payments of £ 1 and £ 2 per session were considered , the cost per QALY fell from £ 12,111 ( base case ) to £ 10,926 and £ 9,741 , respectively . Participants with a mental health risk factor alone or in combination with a risk of chronic heart disease generated a lower ICER ( £ 10,276 ) compared to participants at risk of chronic heart disease only ( £ 13,060 ) . Conclusions Results of cost-effectiveness analyses suggest that NERS is cost saving in fully adherent participants . Though full adherence to NERS ( 62 % ) was higher for the economics sample than the main sample ( 44 % ) , results still suggest that NERS can be cost-effective in Wales with respect to existing payer thresholds particularly for participants with mental health and CHD risk factors . Trial registration Current Controlled Trials IS RCT Background Over the past decade , practitioners in primary health care ( PHC ) setting s in many countries have issued written prescriptions to patients to promote increased physical activity or exercise . The aim of this study is to describe and analyse a comprehensive physical activity referral ( PAR ) scheme implemented in a routine PHC setting in Östergötl and County . The study examines characteristics of the  PARs recipients and referral practitioners , identifies reasons why practitioners opted to use PARs with their clients , and discusses prescribed activities and prescriptions in relation to PHC registries . Methods Prospect i ve prescription data were obtained for 90 % of the primary health care centres in Östergötl and County , Sweden , in 2004 and 2005 . The study population consisted of patients who were issued PARs after they were deemed likely to benefit from increased physical activity , as assessed by PHC staff . Results During the two-year period , a total of 6,300 patients received PARs . Two-thirds of the patients were female and half of the patients were 45–64 years . Half of the patients ( 50.8 % ) who received PARs were recommended a home-based activity , such as walking . One third ( 33 % ) of the patients issued PARs were totally inactive , reporting no days of physical activity that lasted for 30 minutes , and 29 % stated that they reached this level 1–2 days per week . The number of PARs prescribed per year in relation to the number of unique individuals that visited primary health care during one year was 1.4 % in 2004 and 1.2 % in 2005 . Two-thirds of the combined prescriptions were issued by physicians ( 38 % ) and nurses ( 31 % ) . Physiotherapists and behavioural scientists issued the highest relative number of prescriptions . The most common reasons for issuing PARs  were musculoskeletal disorders ( 39.1 % ) and overweight ( 35.4 % ) , followed by high blood pressure ( 23.3 % ) and diabetes ( 23.2 % ) . Conclusion Östergötl and County 's PAR scheme reached a relatively high proportion of physically inactive people visiting local PHC centres for other health reasons . PAR-related statistics , including PAR-rates by individual PHC centres and PAR- rates per health professional category , show differences in prescribing activities , both by patient categories , and by prescribing professionals Background The National Institute for Health and Clinical Excellence in the UK has recommended that the effectiveness of ongoing exercise referral schemes to promote physical activity should be examined in research trials . Recent empirical evidence in health care and physical activity promotion context s provides a foundation for testing the feasibility and impact of a Self Determination Theory-based ( SDT ) exercise referral consultation . Methods An exploratory cluster r and omised controlled trial comparing st and ard provision exercise referral with an exercise referral intervention grounded in Self Determination Theory . Individuals ( N = 347 ) referred to an exercise referral scheme were recruited into the trial from 13 centres . Outcomes and processes of change measured at baseline , 3 and 6-months : Minutes of self-reported moderate or vigorous physical activity ( PA ) per week ( primary outcome ) , health status , positive and negative indicators of emotional well-being , anxiety , depression , quality of life ( QOL ) , vitality , and perceptions of autonomy support from the advisor , need satisfaction ( 3 and 6 months only ) , intentions to be active , and motivational regulations for exercise . Blood pressure and weight were assessed at baseline and 6 months . Results Perceptions of the autonomy support provided by the health and fitness advisor ( HFA ) did not differ by arm . Between group changes over the 6-months revealed significant differences for reported anxiety only . Within arm contrasts revealed significant improvements in anxiety and most of the Dartmouth CO-OP domains in the SDT arm at 6 months , which were not seen in the st and ard exercise referral group . A process model depicting hypothesized relationships between advisor autonomy support , need satisfaction and more autonomous motivation , enhanced well being and PA engagement at follow up was supported . Conclusions Significant gains in physical activity and improvements in quality of life and well-being outcomes emerged in both the st and ard provision exercise referral and the SDT-based intervention at programme end . At 6-months , observed between arm and within intervention arm differences for indicators of emotional health , and the results of the process model , were in line with SDT . The challenges in optimising recruitment and implementation of SDT-based training in the context of health and leisure services are discussed . Trial registration The trial is registered as Current Controlled trials IS RCT N07682833 Background Although the benefits of physical activity ( PA ) on to prevent and manage non-communicable diseases are well known , strategies to help increase the levels of PA among different population s are limited . Exercise-referral schemes have emerged as one effective approach to promote PA ; however , there is uncertainty about the feasibility and effectiveness of these schemes in setting s outside high-income countries . This study will examine the effectiveness of a scheme to refer hypertensive patients identified in Primary Health Care facilities ( PHCU ) of the Mexican social security institution to a group PA program offered in the same institution . Methods and design We will describe the methods of a cluster r and omized trial study design ed to evaluate the effectiveness of an exercise referral scheme to increasing physical activity in hypertensive patients compared to a non-referral scheme .  Four PHCU were selected for the study ; the PHCU will take part as the unit of r and omization and sedentary hypertensive patients as the unit of assessment . 2 PHCU of control group ( GC ) will provide information to hypertensive patients about physical activity benefits and ways to increase it safely . 2 PHCU of intervention group ( IG ) will refer patients to sports facilities at the same institution , to follow a group-based PA program developed to increase the PA levels with a design ed based on the Transtheoretical Model and Social Cognitive Theory . To evaluate the effects of the intervention as well as short-term maintenance of the intervention ’s effects ,  PA  will be assessed at baseline , at 24 and 32 weeks of follow-up . The main outcome will be the difference before and after intervention in the percentage of participants meeting recommended levels of PA  between and within intervention and control groups . PA will be measured through self-report and with objective measure by accelerometer . Discussion This study will allow us to evaluate a multidisciplinary effort to link the primary care and community-based areas of the same health care system . Our findings will provide important information about the feasibility and effectiveness of an exercise-referral scheme and will be useful for decision-making about the implementation of strategies for increasing PA among hypertensive and other clinical population s in Mexico and Latin America . Trial registration Clinical trials.gov Identifier : NCT01910935 . Date of registration : 07/05/2013 Study objective : To compare health walks , a community based lay-led walking scheme versus advice only on physical activity  and cardiovascular health status in middle aged adults . Design : R and omised controlled trial with one year follow up . Physical activity was measured by question naire . Other measures included attitudes to exercise , body mass index , cholesterol , aerobic capacity , and blood pressure . Setting : Primary care and community . Participants : 260 men and women aged 40–70 years , taking less than 120 minutes of moderate intensity activity per week . Main results : Seventy three per cent of people completed the trial . Of these , the proportion increasing their activity above 120 minutes of moderate intensity activity per week was 22.6 % in the advice only and 35.7 % in the health walks group at 12 months ( between group difference = 13 % ( 95 % CI 0.003 % to 25.9 % ) p=0.05 ) . Intention to treat analysis , using the last known value for missing cases , demonstrated smaller differences between the groups ( between group difference = 6 % ( 95 % CI −5 % to 16.4 % ) ) with the trend in favour of health walks . There were improvements in the total time spent and number of occasions of moderate intensity activity , and aerobic capacity , but no statistically significant differences between the groups . Other cardiovascular risk factors remained unchanged . Conclusions : There were no significant between group differences in self reported physical activity at 12 month follow up when the analysis was by intention to treat . In people who completed the trial , health walks was more effective than giving advice only in increasing moderate intensity activity above 120 minutes per week OBJECTIVES To evaluate and compare the effectiveness and cost-effectiveness of a leisure centre-based exercise programme , an instructor-led walking programme and advice-only in patients referred for exercise by their GPs . DESIGN A single-centre , parallel-group , r and omised controlled trial , consisting of three arms , with the primary comparison at 6 months . SETTING Assessment s were carried out at Copthall Leisure Centre in Barnet , an outer London borough , and exercise programmes conducted there and at three other leisure centres and a variety of locations suitable for supervised walking throughout the borough . PARTICIPANTS Participants were aged between 40 and 74 years , not currently physically active and with at least one cardiovascular risk factor . INTERVENTIONS The 943 patients who agreed to participate in the trial were assessed in cohorts and r and omised to one of the following three arms : a 10-week programme of supervised exercise classes , two to three times a week in a local leisure centre ; a 10-week instructor-led walking programme , two to three times a week ; an advice-only control group who received tailored advice and information on physical activity including information on local exercise facilities . After 6 months the control group were rer and omised to one of the other trial arms . Assessment s took place before r and om 
    Output:
    
Results from meta-analyses show that PARS had an effect on the adherence rate of physical activity , while the results from the meta-regressions show that programme characteristics such as type of chronic disease and the follow-up period influenced the adherence rate .
CONCLUSIONS The effects of PARS on adherence and self-reported physical activity were influenced by programme characteristics and also by the design of the study .