A Randomized Trial of Economic Incentives to Promote Walking Among Full Time Employees

The first part of this study comprises an in-home face-to-face survey with 950 full-time employees in Singapore. The survey aims to identify what an optimal programme might look like and to quantify the potential uptake of the programme, if offered. Stated preference conjoint analysis, which assesses individual preferences for attributes of specific programmes, will be used.

The second part of this study is a Randomised Controlled Trial (RCT) of a 12-month walking programme. Up to 800 full-time employees will be recruited and allocated to one of four research arms: Control Group, Programme Only Group, Cash Incentive Group and Charitable Incentive Group. Participants in the intervention arms will be asked to track their physical activities using Fitbit Zip, a wireless pedometer, which automatically uploads the data to a custom website. Those in the incentive arms will earn money or raise money for charities if they meet weekly exercise targets. Those in the control and Programme Only groups with receive a weekly payment for participation. Incentives and participation payment will be provided from months 1 - 6, after which they will be withdrawn.

The key outcome variable of the RCT is defined as bouts (in minutes) of moderate to vigorous physical activity ("MVPA bouts") as measured via accelerometry. Data will be collected at baseline and month 6 and 12 assessments.

Findings from the RCT will also be used to determine the cost to employers of implementing each programme and the incremental cost-effectiveness of the incentive programmes compared to the basic programme without incentives. The primary hypotheses are that the basic programme will have lower costs per person than the cash or charity programmes, but that the incentive programmes will be more cost-effective relative to the less expensive and less effective basic programme.