A Longitudinal Study of Severe and Enduring Eating Disorders

Eating disorder examination interview (EDE-I)

EDE-I is a semi-structured interview for assessing symptoms of and diagnosing eating disorders, including providing information for grading severity according to e.g., the DSM 5. The EDE-I assesses a variety of eating disorder behaviors, weight control behaviors, and behavioral and cognitive features of eating disorder psychopathology.

Eating disorder Examination Questionnaire (EDE-Q)

EDE-Q is a 28-item self-report questionnaire, designed to assess the range, frequency and severity of behaviors associated with an eating disorder. It is categorized into four sub-scales: Restraint, Eating Concern, Shape Concern and Weight Concern, and an overall global score. The score is obtained by calculating the mean for the total score and the subscales respectively (min = 0, max =6), higher scores indicate more severe eating disorder symptoms.

Eating Disorder-15 (ED-15) and for parents/caregivers (ED-15-P)

ED-15 assesses eating disorder attitudes and behaviors on a 15-item Likert scale, which includes 10 attitudinal items (scored from 0-6) and 5 items for frequency grading. ED-15-P include the same items but is answered by the youths caregiver instead. The ED-15 includes two attitudinal subscales: Weight \& shape concerns and Eating concerns. The Overall attitudinal score is the mean of the scores on all ten items. Higher scores indicate more severe eating disorder symptoms.

Clinical Global Impression-Severity (CGI-S)

Global clinical rating of symptom severity on an 8-grade Likert scale (scored between 0-7). The CGI offers a clinician-determined summary that incorporates all available information, including the patient's history, psychosocial context, symptoms, behavior, and the impact of these symptoms on their functional ability. A higher score indicates a more severe psychopathology.

Clinical Impairment Assessment questionnaire (CIA)

The CIA is a 16-item self-report measure of the severity of psychosocial impairment due to eating disorder features, Each item is rated on a four-point Likert scale ranging from 'Not at all' to 'A lot'. The minimun score is zero and the maximum score is 48, with higher scores indicating a more severe impairment.

WHO Disability Assessment Schedule (WHODAS 2.0)

WHODAS 2.0 measure individual dysfunction in six domains of daily activities (cognition, mobility, self-care, relationships with people, life activities, and participation). It is measured on a five-point Likert scale ranging from no difficulty, to extreme difficulty. The score is calculated by dividing the total score with the number of items, resulting in a minimum score of zero and maximum score of 4. Higher scores indicate higher disability.

Uppsala scale of Functional Impairment in Daily life (UFID and UFID-P for parents)

The UFID is a Five-item, five-point Likert scale that measures functional impairment in daily life on a score between 1-5. UFID-P includes the same items but is answered by the caregiver instead. Higher scores indicate more functional impairment.

Children's Global Assessment Scale (CGAS)

CGAS is a rating of general functioning for children and young people aged 4-16 years old. The clinician assesses a range of aspects of psychological and social functioning and gives the child or young person a single score between 1 and 100, based on their lowest level of functioning.

The Avoidance and Fusion Questionnaire for Youth (AFQ-Y)

The AFQ-Y is a self-rating instrument that measures psychological inflexibility. Participants rate their level of agreement on eight items on a 5-point Likert measuring one single factor. Score range is 0-24 and higher scores indicate a higher level of psychological inflexibility.

Emotion Regulation Questionnaire (ERQ)

The ERQ is a self-rating instrument designed to assess individual differences in the use of emotion regulation strategies. It is composed of ten items divided into two factors: cognitive reappraisal and expressive suppression. Participants indicate their answers on a 7-point Likert-scale ranging from 1 (total disagreement) to 7 (total agreement).

Swedish universities Scale of Personality (SSP)

SSP is a self-report instrument assessing personality traits corresponding to biological correlates. It contains 91 items divided into 13 subscales. The scale can also be divided into a three-factor solution with Factor 1 reflecting Neuroticism; Factor 2 reflecting Aggressiveness; and Factor 3 reflecting Extraversion. Each item is given as a statement with a four-point response format, ranging from does not apply at all to applies completely. It is presented in standardized t-score ranging from 0-100 (mean 50 and standard deviation 10). Higher scorer indicate more pronounced characteristics of that specific trait.

Neuroticism-Extraversion-Openness Personality Inventory (NEO-PI)

The NEO-PI is a self-report instrument designed to assess personality traits based on the Five-Factor Model of personality. It consists of 240 items grouped into five main domains: Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Each domain is further divided into six specific facets, providing a detailed profile of personality traits. Responses are rated on a five-point Likert scale, ranging from "Strongly Disagree" to "Strongly Agree." Scores are typically presented as standardized T-scores, with higher scores indicating a stronger expression of the respective traits.