Title: | Randomised controlled trial of efficacy of a family based programme to increase physical activity among individuals at high risk of diabetes (Pro-active Study) |
Principal research question: | Can an innovative approach to increasing physcial activity achieve clinically important change in this behaviour when offered to a group at increased risk of diabetes? If so, what is the potential for the changes in behaviour achieved in midlife to reduce the incidence of obesity and diabetes in later life? How does delivery of the approach, at two levels of intensity, affect acceptability, efficacy and costs? |
Methodology description: | Willing, sedentary offspring (aged >30yr) are recruited via their parents with diabetes on primary care registers. Measures at baseline allow ascertainment of sociodemographic, psychological and physiological parameters likely to affect outcomes. Measures at 4 and 12 months allow ascertainment of the effect of interventions on physical activity and its mediators in the short and medium term. Measures at twelve months also allow ascertainment of biochemical and physiological correlates of physical activity for modelling the impact of the intervention on subsequent disease status. 1) Patient Flow. We estimate that recruitment of 400 families can be completed in 20 months, and intervention at intensive and minimal levels by 32 months. With a conservative estimate of 50% of families approached participating, and 75% of these completing one year folllow up we will need to recruit 8 practices and approach 800 offspring for a completion rate of 100/group. 2) Interventions.All trial participants are aware from recruitment that family history increases risk of diabetes and that physical activity may moderate this risk. Information on follow-up measures for the control group is provided by telephone contact with the research officer. A fascilitator contacts offspring randomised to intervention groups and arranges a home interview with them and their families. At this ‘motivating interview’ reasons for taking part in the programme and increasing physical activity are explored and strenghened. In the intensive arm this is followed by a four-month home-based programme of 4 visits and 2 telephone calls. These establish skills in selection and implementation of achievable activities, and their maintenance. Support materials are under pilot, and Digiwalker pedometers will be used to self-monitor activity. Follow-up continues by correspondence and monthly telephone calls for 8 months. In the minimal arm, there is only one home interview when use of materials and initial goals are also agreed. Subsequent face-to-face skills meetings are omitted and support is by correspondence and monthly telephone call alone. |
Sample group description: | Willing sedentary offspring (aged >30) are recruted via their parents with diabetes on primary care registers. |
Outcome measure description: | Outcomes will be compared across groups at 4/12 and one year follow-up. 1) Acceptability: Recruitment and attrition rates in the three study arms will be compared. 2) Effectiveness: The primary outcome is physical activity level (objective measure developed in house). Other measures include cardiovascular risks, and individual and family beliefs, attitudes and health related behaviours. 3) Causal Pathway: Our causal model links social context, attitudes, beliefs, interventions and behaviours through biochemical and physiological correlates to future disease states. Study data will be linked to other cohort studies to model potential contributions to relieving later disease burden. |
UK ISRCT Number: | 61323766 |
Project organisation | |
Start date: | 1st April 2001 |
End date: | 31st March 2005 |
Contact person: | Dr Kate Williams |
Contact Details: | ProActive Study General Practice & Primary Care Research Unit IPH, Forvie Site, Robinson Way Cambridge Cambs CB2 2SR UK Telephone: (01223) 330332 Fax: 01223 762515 E-mail: proactive@medschl.cam.ac.uk |
Funding information | |
Funding Organisation: | Medical Research Council |
Funding Reference: | G0000753 |
Funding Amount: | £342,048 |
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References and Publications | |