OBJECTIVES: Understanding immediate improvements in health related quality-of-life (HRQoL) due to better glycaemic control may help inform decisions relating to the management of diabetes. This study investigated the short-term impact on HRQoL associated with HbA change, body weight change, and the complexity of treatment regimen, using time-trade-off (TTO) methodology METHODS: The study was performed in three stages: 1) Qualitative telephone interviews with people with type 2 diabetes (T2D) in Denmark who experienced a decrease in their HbA level; 2) A validation survey with people with T2D in Denmark to obtain quantifiable knowledge on the short-term effects of a change in HbA levels; 3) TTO survey using health states based on results from stage 2. ‘Not well-controlled diabetes’ reflected an HbA average of 11.6%, and ‘well-controlled diabetes’ an HbA average of 7.4%. All other health states were based on ‘well-controlled diabetes’. These health states implied change in insulin regimen and change in weight. Respondents were either adults with T2D (Sweden) or from the general public (UK and Denmark) and were separately randomly allocated to evaluate 6 of the 10 health states through an internet-based survey. RESULTS: In total,