Table 1 Overview of the assessment instruments used throughout each stage of the study

Weight Concern Scale (WCS)

X

-

-

-

-

-

-

Short Evaluation of Eating Disorders (SEED)

X

X

-

-

X

X

X

Short Evaluation of Eating Disorders II (SEED-II)

-

-

X

X

-

-

-

Demographics and other information

-

X

-

-

-

-

-

Monitoring questionnaire

-

-

X

X

-

-

-

Patient Health Questionnaire 4 (PHQ-4)

-

X

-

X

X

X

X

Perseverative Thinking Questionnaire (PTQ)

-

X

-

X

X

X

X

Eating Disorder Examination Questionnaire (EDE-Q)

-

X

-

-

X

X

X

Self-stigma of seeking help

-

X

-

-

X

X

X

Self-esteem, mastery and support

-

X

-

-

X

X

X

Eating Disorder-related Quality of Life (ED-QOL)

X

-

-

X

X

X

Motivation to change

-

X

-

-

X

X

X

Session Rating Scale (SRS)

-

-

X¹

-

-

-

-

User satisfaction questionnaire

-

-

-

-

X²

-

-

Attrition follow-up question

-

-

X³

X³

X³

X³

X³

Help-seeking attitudes and behavior questionnaire

-

-

-

-

X

X

X

Quality of life (EuroQol: EQ-5D)

-

X

-

-

X

X

X

Trimbos/iMTA questionnaire for costs associated with psychiatric illness

-

X

-

-

X

X

X