Design of a pragmatic cluster randomised controlled trial: Ecological approach to increasing physical activity in an urban community

Abstract

This study was set up to test an ecological intervention using a pragmatic cluster randomised controlled design (RCT) aimed at increasing physical activity (PA) within the community in a deprived inner-city area in the UK. The research will provide a detailed mapping (using Graphical Information Systems GIS) of the environment at lower super output area (SOA) level in Stoke-on-Trent (SoT) and will evaluate the relationship between the environment, PA behaviour, health and healthcare utilisation. The environmental mapping will aggregate data from a wide range of available databases, augmented by local data gathering and validation, to produce a comprehensive geo-coded map of 10 SOAs (covering a population ~15,000). GIS will be used to derive indices through which to evaluate the relationship between environmental characteristics and levels of physical activity and health, using Hierarchical Linear Modelling (HLM). Environmental indices used will include: proximity of PA spaces and facilities, street connectivity, land use mix, population density, mass transport provision, traffic, safety, crime, proximity of food outlets and shops, “Walkability Index”, weather and indices of multiple deprivation (IMD). The areas for mapping, baseline assessment and intervention will be considered in two parts, a) community-based and b) schools-based. The effectiveness of the community-based intervention will be assessed by an independent panel survey conducted at baseline and at 2 years follow-up, with an expected 10% increase in the proportion of the population more active in the intervention arm. Effectiveness of the schools-based intervention will be designed to detect an increase of ~15 min/day in school children's moderate to vigorous PA (MVPA). Resource use, cost, willingness to pay and incidental consequences data will be collected alongside the community-based intervention to enable economic modelling from health and social care, societal, other public service and participant perspectives. Findings from the project will inform public policy for increasing population PA and improving neighbourhoods and urban design.