Task: evaluate effectiveness of additional promotional intervention

The second main task is to evaluate the effectiveness of the additional promotional intervention in a randomised controlled trial.

We are developing three arms to the trial, in which local households will be exposed to:

1. the Connect2 infrastructural improvements only;
2. Connect2 infrastructural improvements plus a low-technology intervention using traditional low-cost printed self-help materials; or
3. Connect2 infrastructural improvements plus a high-technology intervention using the visual imaging techniques described elsewhere to personalise the opportunities for walking and cycling provided by the new infrastructure.

Households in the study area are allocated to one of these three arms using a randomisation procedure clustered by small area (e.g. by unit postcode) to minimise the likelihood of contamination between groups. The self-help intervention is delivered shortly after the infrastructural intervention has been completed.

In effect, this trial constitutes a 'special case' of the intervention case studies.

We will collect and analyse baseline and follow-up data in the way described above under workpackage 3. We will collect additional qualitative data to gain further insight into participants' reaction to, engagement with and use of the promotional materials and the facilitators of and barriers to their taking up the opportunities provided by the infrastructural intervention. We will also conduct an economic evaluation of the costs, resource savings and effectiveness of additional promotional interventions drawing upon previous work in this area (Powell) for the Health Development Agency (Kelly et al., 2005).