This study measured cognitions relating to hypoglycaemia over a 24-month period in adults with type 1 diabetes and IAH, examining the potential of the HypoCOMPaSS intervention (brief psycho-education and optimisation of insulin treatment with glucose monitoring to reduce hypoglycaemia) to modify attitudinal barriers to hypoglycaemia avoidance, and investigate whether such cognitions, and/or changes in them from baseline to 24 weeks, predict incomplete response to the programme, defined by at least one severe hypoglycaemia episode over the 24-month follow-up period. This evidence concerns the gene INS and type 1 diabetes mellitus.