Intentional and inadvertent non-adherence in adult coeliac disease. A cross-sectional survey

•Non-adherence to the gluten-free diet involves intentional and inadvertent lapses.•Intentional lapses are common but less frequent than inadvertent lapses.•Contributing factors affect both types of non-adherence in different ways.•Intention, perceived tolerance and self-efficacy predicted intentional lapses.•Psychosocial factors do not explain inadvertent lapses as well as intentional ones. Adherence to a gluten-free diet is the mainstay of treatment for coeliac disease. Non-adherence is common as the diet is restrictive and can be difficult to follow. This study aimed to determine the rates of intentional and inadvertent non-adherence in adult coeliac disease and to examine the factors associated with both. A self-completion questionnaire was mailed to adult coeliac patients identified from the computer records of 31 family practices within the North East of England. We received 287 responses after one reminder. Intentional gluten consumption was reported by 115 (40%) of respondents. 155 (54%) had made at least one known mistaken lapse over the same period and 82 (29%) reported neither intentional nor mistaken gluten consumption. Using logistic regression analysis, low self-efficacy, perceptions of tolerance to gluten and intention were found to be independently predictive of intentional gluten consumption. A statistical model predicted 71.8% of cases reporting intentional lapses. Intentional non-adherence to the GFD was found to be common but not as frequent as inadvertent lapses. Distinguishing the factors influencing both intentional and inadvertent non-adherence is useful in understanding dietary self-management in coeliac disease.