Establishing consensus for labeling and defining the later stage of anorexia nervosa: A Delphi study

Varied perspectives on the later stage of anorexia nervosa (AN) have left the field of eating disorders without a consistent label or definition for this subpopulation. As a result, diverse criteria when recruiting participants have led to incomparable results across research studies and a lack of guidance when assessing and treating patients in the clinical context. The aim of the current study was to develop consensus-based guidelines on the labeling and defining of the later stage of AN.

Utilizing the Delphi methodology, a professional panel of experts (N = 21) participated in three rounds of questionnaires. Five open-ended questions (Round 1) were analyzed using content analysis to form statements relating to a classification system for labeling and defining the later stage of AN. A total of 80 statements were rated in terms of panelists' level of agreement (Rounds 2 and 3).

Consensus was achieved for 28.8% of statements and a further 16.3% of statements reached near consensus in the second and third round of questionnaires. Two labels were identified with five defining features achieving consensus.

Findings from the study suggest an alternative approach to labeling be adopted with consensus-based guidelines established for defining the later stage of AN. Implications that may occur from a unified classification system are explored with longitudinal research required to assess the impact on patients experiencing the later stage of AN.