Evaluating the travel, physical activity and carbon impacts of a ‘natural experiment’ in the provision of new walking and cycling infrastructure: methods for the core module of the iConnect study
- David Ogilvie1,
- Fiona Bull2,
- Ashley Cooper3,
- Harry Rutter4,
- Emma Adams2,
- Christian Brand4,
- Karen Ghali5,
- Tim Jones4,
- Nanette Mutrie6,
- Jane Powell7,
- John Preston5,
- Shannon Sahlqvist1,
- Yena Song5 on behalf of the iConnect Consortium
- 1Medical Research Council Epidemiology Unit and UKCRC Centre for Diet and Activity Research (CEDAR), Institute of Public Health, Cambridge, UK
- 2School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- 3Centre for Exercise, Nutrition and Health Sciences, School for Policy Studies, University of Bristol, Bristol, UK
- 4Environmental Change Institute, University of Oxford, Oxford, UK
- 5School of Civil Engineering and the Environment, University of Southampton, Southampton, UK
- 6School of Psychological Sciences and Health, University of Strathclyde, Glasgow, UK
- 7Centre for Health and Clinical Research, University of the West of England, Bristol, UK
- Correspondence to Dr David Ogilvie;
- Received 29 November 2011
- Accepted 16 December 2011
- Published 2 February 2012
Introduction Improving infrastructure to support walking and cycling is often regarded as fundamental to encouraging their widespread uptake. However, there is little evidence that specific provision of this kind has led to a significant increase in walking or cycling in practice, let alone wider impacts such as changes in overall physical activity or carbon emissions. Connect2 is a major new project that aims to promote walking and cycling in the UK by improving local pedestrian and cycle routes. It therefore provides a useful opportunity to contribute new evidence in this field by means of a natural experimental study.
Methods and analysis iConnect is an independent study that aims to integrate the perspectives of public health and transport research on the measurement and evaluation of the travel, physical activity and carbon impacts of the Connect2 programme. In this paper, the authors report the study design and methods for the iConnect core module. This comprised a cohort study of residents living within 5 km of three case study Connect2 projects in Cardiff, Kenilworth and Southampton, supported by a programme of qualitative interviews with key informants about the projects. Participants were asked to complete postal questionnaires, repeated before and after the opening of the new infrastructure, which collected data on demographic and socioeconomic characteristics, travel, car fuel purchasing and physical activity, and potential psychosocial and environmental correlates and mediators of those behaviours. In the absence of suitable no-intervention control groups, the study design drew on heterogeneity in exposure both within and between case study samples to provide for a counterfactual.
Ethics and dissemination The study was approved by the University of Southampton Research Ethics Committee. The findings will be disseminated through academic presentations, peer-reviewed publications and the study website (http://www.iconnect.ac.uk) and by means of a national seminar at the end of the study.
This paper was written on behalf of the iConnect consortium (http://www.iconnect.ac.uk; Christian Brand, Fiona Bull, Ashley Cooper, Andy Day, Nanette Mutrie, David Ogilvie, Jane Powell, John Preston and Harry Rutter).
To cite: Ogilvie D, Bull F, Cooper A, et al. Evaluating the travel, physical activity and carbon impacts of a ‘natural experiment’ in the provision of new walking and cycling infrastructure: methods for the core module of the iConnect study. BMJ Open 2012;2:e000694. doi:10.1136/bmjopen-2011-000694
Funding The iConnect consortium is funded by the Engineering and Physical Sciences Research Council (grant reference EP/G00059X/1). DO is also supported by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence. CEDAR is funded by the British Heart Foundation, Economic and Social Research Council, Medical Research Council, National Institute for Health Research and the Wellcome Trust, under the auspices of the UK Clinical Research Collaboration (http://www.ukcrc.org/researchcoordination/jointfund/publichealth).
Competing interests None declared.
Ethics approval The study was approved by the University of Southampton Research Ethics Committee (reference number CEE 200809-15).
Contributors All authors contributed to the development of the study protocol and core survey instrument. DO wrote the first draft of the paper with FB, AC and HR. All authors contributed to the critical revision of the paper and approved the final version.
Provenance and peer review Not commissioned; internally peer reviewed.
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