Examining the Behaviour subscale of the Hypoglycaemia Fear Survey: an international study

The Hypoglycemia Fear Survey (HFS)-II Behaviour and Worry subscales were developed to measure behaviours and anxiety related to hypoglycaemia in diabetes. However, previous studies found lower reliability in the HFS Behaviour subscale and inconsistent relationships with glucose control. The purpose of this study was to conduct extensive analyses of the internal structure of the HFS Behaviour subscale's internal structure and its relationships with diabetes outcomes, including HbA1c and episodes of severe hypoglycaemia. HFS-II survey data from 1460 adults with Type 1 diabetes were collected from five countries. This aggregated sample underwent exploratory factor analysis and item analysis to determine the internal structure of the survey and subscales. A three-factor solution showed the best fit for the HFS, with two subscales emerging from the HFS Behaviour representing tendencies towards (1) maintenance of high blood glucose and (2) avoidance of hypoglycaemic risks by other behaviours, and a third single HFS Worry subscale. Subscale item analysis showed excellent fit, separation and good point-measure correlations. All subscales demonstrated acceptable (0.75) to excellent (0.94) internal reliability. HbA(1c) correlated with Maintain High Blood Glucose subscale scores, r = 0.14, P < 0.001, and severe hypoglycaemia frequency correlated with all subscales. The HFS Worry subscale measures one construct of anxiety about various aspects of hypoglycaemia. In contrast, the HFS Behaviour subscale appears to measure two distinct aspects of behavioural avoidance to prevent hypoglycaemia, actions which maintain high blood glucose and other behaviours to avoid hypoglycaemic risk. These results demonstrate the clinical importance of the HFS Behaviour subscales and their differential relationships with measures of diabetes outcome such as HbA1c