PMU33 - Economic Evaluation of A Randomised Controlled Trial of An Intervention to Reduce Desk-Based Workers' Sitting Time: The Stand-Up Victoria Trial

Abstract

Interventions to reduce workplace sitting time have been shown to be effective, but little is known about their cost-effectiveness. This study assessed the economic credentials of a workplace-delivered intervention to reduce sitting time in desk-based workers. Within-trial cost-efficacy analysis and long-term cost-effectiveness analysis (CEA) modelled for the Australian population were performed. In total, 231 desk-based workers aged 24-65 years of one organisation were recruited in a clustered randomized controlled trial. A multicomponent workplace-delivered intervention (including organizational, environmental [sit-stand workstations], and individual [health coaching] intervention elements) was compared to usual practice. Total device-measured workplace sitting time (primary), Body Mass Index (BMI: kg/m2), self-reported health-related quality of life (measured by Assessment of Quality of Life-8D), and absenteeism were measured at 12 months. Compared to usual practice, the intervention was associated with greater cost (AUD431/person) and benefits in terms of reduced workplace sitting time (-46.8 mins/8-h workday, 95% confidence interval: -69.9 to -23.7) and increased workplace standing time (42.2 mins/8-h workday, 23.8 to 60.6). However, there were no significant benefits for BMI (0.148 kg/m2 [-1.407 to 1.703]), AQoL-8D (-0.006 [-0.074 to 0.063]) or absenteeism (2.12 days [-2.01 to 6.26]). The incremental cost-efficacy ratios ranged from AUD9.94 cost/minute reduction in workplace sitting time to AUD13.37/minute reduction in overall sitting time. The intervention contributed to higher life year gains (LY) (0.01 [0.009 to 0.011]), higher health-adjusted life year gains (HALY) (0.012 [0.0105 to 0.0135]), and higher net costs (AUD344 [$331 to $358]), with corresponding incremental cost effectiveness ratios of AUD34,443/LY and $28,703/HALY. CEA results were sensitive to assumptions surrounding intervention-effect decay rate and discount rate. The intervention was cost-effective over the lifetime of the cohort when scaled up to the national workforce. It provides important evidence for policy makers and workplaces regarding allocation of resources to reduce workplace sitting.