Objectives This study aims to evaluate the effectiveness of a "blended" workplace health-promotion intervention, alongside identification of key components beneficial for future implementation strategies. Methods Within a cluster randomized controlled trial, 491 employees at increased risk of cardiovascular disease were allocated to the limited (N=217; 9 clusters) or extensive (N=274; 8 clusters) intervention. The extensive intervention consisted of motivational interviewing (MI) within the framework of a web-based health risk assessment (HRA), a blended care approach. The limited intervention received solely the web-based HRA. Occupational health physicians (N=21) within three organizations delivered the intervention. Implementation components investigated included: HRA (reach and participation), newsletters (percentage read), and MI sessions (number and quality). MI quality was determined by scoring audiotaped MI sessions, using the MI treatment integrity code. After 6 and 12 months, effects on participation in health-promotion activities and its associations with components of implementation were determined by mixed-effects models. Results Over 80% of employees participated in health-promotion activities, with an additional 8% in the extensive compared to the limited group. In the extensive intervention, those with more or better quality MI sessions were more likely to participate in health-promotion activities. Increased MI quality was associated with sustained participation. Conclusions This study suggests that participation in health-promotion activities can be increased by adding MI to a web-based approach and improving the quality of the MI delivered. Interventions with MI should include optimized delivery and quality of MI sessions.

Additional Metadata
Keywords Blended care, Cardiovascular disease, Cluster randomized controlled trial, Health promotion, Health-promotion activity, Implementation, Lifestyle intervention, Motivational interviewing, Randomized controlled trial, RCT, Risk assessment, Web-based health risk assessment, Workplace intervention
Persistent URL dx.doi.org/10.5271/sjweh.3716, hdl.handle.net/1765/109229
Journal Scandinavian Journal of Work, Environment and Health
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Citation
Kouwenhoven-Pasmooij, T.A, Robroek, S.J.W, Nieboer, D, Helmhout, P.H. (Pieter H.), Wery, M.F, Hunink, M.G.M, & Burdorf, A. (2018). Quality of motivational interviewing matters: The effect on participation in health-promotion activities in a cluster randomized controlled trial. Scandinavian Journal of Work, Environment and Health, 44(4), 414–422. doi:10.5271/sjweh.3716