Title: A three arm cluster randomised controlled trial to test the effectiveness and cost-effectiveness of the SMART Work & Life intervention for reducing daily sitting time in office workers
Funder: Department of Health and Social Care

Abstract: Background: Office-based workers spend 70-80% of working hours sitting and typically spend large proportions of their time sitting during leisure time. High levels of sitting have been linked to poor health including type 2 diabetes, cardiovascular disease, some cancers and mortality. Current evidence shows a need for fully powered randomised controlled trials (RCTs) with long term follow up to test the effectiveness of interventions to reduce sitting. Previous Work: Our group spent 18 months developing and testing a multi-component (organisational, environmental and individual strategies) intervention (delivered with the provision of a height-adjustable workstation), to reduce workplace sitting in NHS office workers (SMArT Work). SMArT Work has now been refined and extended based on a full process evaluation, our collaborators’ experiences in Australia, and recently published research - now called SMART Work & Life. To address gaps in existing interventions, SMART Work & Life will go beyond sitting in the workplace by also focusing on behaviour change outside of the workplace to emphasise a ‘whole-of-day’ preventive approach as well as enhancing behaviour change maintenance. Aim: To determine the effectiveness and cost-effectiveness of the SMART Work & Life intervention, delivered with and without a height-adjustable workstation, for reducing daily sitting time, compared with control. Research Plan: A 3 arm cluster RCT will be conducted. A powered sample of 33 office clusters (660 office workers who spend the majority of their waking hours sitting) will be recruited from councils in 2 areas in England– Leicester and Manchester). Upon completion of baseline measures, office groups (clusters) will be randomised to receive the multi-component SMART Work & Life intervention delivered with (intervention group 1) or without (intervention group 2) a height-adjustable workstation or a usual care control group (group 3). SMART Work & Life (guided by the Behaviour Change Wheel) includes organisational (e.g., management buy-in, provision for standing meetings, competitions), environmental (e.g., relocating waste bins, printers) and group/individual (education, action planning, goal setting, addressing barriers, coaching, self-monitoring) level behaviour change strategies, driven by workplace champions within the council. Baseline, 3, 12 and 24 month measures will be taken. Primary outcome: Objectively measured daily sitting time. Secondary outcomes: objectively measured sitting, standing, stepping and prolonged sitting time and number of steps at work; objectively measured daily standing, stepping, prolonged sitting time, moderate-to-vigorous physical activity and sleep (wrist accelerometry). Adiposity, blood pressure, and glycated haemoglobin, cholesterol (total, HDL, LDL) and triglycerides will be assessed from finger prick blood samples. Questionnaires will examine dietary components (alcohol, snacks, sugary drinks), vitality, fatigue, musculoskeletal issues, job performance and satisfaction, work engagement, presenteeism, stress, anxiety and depression. Health related quality of life and resources used (e.g. GP visits, outpatient attendances) will also be assessed. Sickness absence data will be collected from organisational records. We will conduct a full process evaluation and cost-effectiveness analysis. Impact: The results of this RCT will provide evidence for policy guidelines around population and workplace health and well-being.

Lay abstract: People whose job primarily involves desk based work spend a large proportion of their day sitting down at work and many of these individuals also sit a lot when they are at home. High levels of sitting have been linked to diseases such as type 2 diabetes, heart disease, and some cancers. This makes office workers an ‘at-risk’ group and who should be targeted for lifestyle intervention. Our team has developed an intervention called SMART Work & Life that is designed to reduce the time that office workers spend sitting both inside and outside of work, emphasising a ‘whole-of-day’ preventive approach. Previous interventions have only focused on sitting at work. This intervention has been based on previous work that the research team has conducted over the past couple of years targeting sitting at work (SMArT Work). Our SMART Work & Life intervention involves multiple strategies including those at the organisational (e.g., provision for standing meetings, competitions), environmental (e.g., relocating waste bins, printers) and group/individual (education, goal setting, progress sessions, technology to track and provide feedback on their own sitting time) level to encourage a reduction in sitting time both in and out of the workplace. Workplace champions (employee representatives) within local councils will deliver some of these strategies. This intervention will be delivered with and without the provision of a height-adjustable workstation (allows the user to either stand or sit to work). This is important because although our previous research has achieved substantial reductions in workplace sitting, there are cost implications associated with these workstations so it is important to also evaluate the impact of the intervention without this resource. To test how effective our SMART Work & Life intervention, with and without a height-adjustable workstation is, we will recruit 33 office groups, involving 660 office workers, within local councils in Leicester and Manchester. One third of office groups will receive the intervention and a height-adjustable workstation, one third will receive the intervention without a height-adjustable workstation and one third will act as a comparison group (carry on as normal). Our research team will measure how much office workers sit during the day (inside and outside of work) using a physical activity device worn on the thigh for 7 days. This monitor also provides an accurate measure of daily steps taken, time standing, and time being active. We will also take a number of measures of health including weight, body fat, waist circumference, blood pressure, and take a finger prick blood sample to analyse levels of blood sugar and cholesterol. Participants will be asked to complete some questions about their health and work. These measurements will be taken from all participants before the intervention begins, and again at 3, 12 and 24 months after the first set of measurements. No interventions targeting sitting have followed participants over this length of time before. This will allow us to assess whether participants maintain any behaviour change over the long term. We will also talk to a number of office workers and workplace champions throughout the intervention delivery period about their experiences of the various strategies. Our research team will also test whether our intervention, with and without a height-adjustable desk, is value for money.

Research activity codes: 2.2 FACTORS RELATING TO PHYSICAL ENVIRONMENT;3.1 PRIMARY PREVENTION INTERVENTIONS TO MODIFY BEHAVIOURS OR PROMOTE WELL-BEING
Health categories: CANCER AND NEOPLASMS;CARDIOVASCULAR;METABOLIC AND ENDOCRINE;ORAL AND GASTROINTESTINAL;STROKE