Reducing sedentary time in adults at risk of type 2 diabetes: process evaluation of the STAND (Sedentary Time ANd Diabetes) RCT

BACKGROUND: Reducing sedentary behaviour may have important health implications. This study evaluated the potential enablers and barriers for outcomes of a randomised controlled trial (RCT) designed to evaluate a pragmatic education based intervention designed to reduce sedentary (sitting) behaviour in young adults at high risk of type 2 diabetes. METHODS: Data were collected from participants in the intervention group immediately after an educational workshop addressing sedentary time and diabetes risk (n = 71), through phone interviews 6 weeks (n = 45) after the workshop, and at the conclusion of the 12-month trial (n = 10). The two education session facilitators were also interviewed about the intervention. RESULTS: The RCT showed no difference in sedentary time at 12 months between intervention and control arms. The lack of behaviour change appeared not to be attributed to the workshops, which were well led and very favourably received according to feedback. However, factors contributing to this lack of behaviour change include lack of perceived health risk from baseline measures feedback; the preference to adopt physically active behaviours rather than to sit less; certain barriers to sitting less; motivational drift after the 3-month follow-up measurements where participants had no contact for a further 9 months; and, for some, unreliability of the self-monitoring tool. CONCLUSIONS: The workshop was well led and well received by the attendees but future interventions need to consider more contact with participants, discuss any specific benefits around simply standing to reduce sitting time, address the barriers to sitting less, and provide a more user-friendly and reliable self-monitoring tool. TRIAL REGISTRATION: Current controlled trials ISRCTN08434554, MRC project 91409. Registered retrospectively on 22 February 2011.