Table 1.
Psychological questionnaires used in the present trial (* reported from the literature).
| Variable | Questionnaire | Cronbach‘s Alpha * |
|---|---|---|
| Well-being | Well-being questionnaire (Berner Fragebogen zum Wohlbefinden (BFW)) [25] | 0.84 |
| Quality of life | Questionnaire for the assessment of disease-related quality of life (Fragebogen zur Erfassung der gesundheitsbezogenen Lebensqualität von Kindern und Jugendlichen (Kindl-R)) [26] | 0.49–0.86 |
| Weight-related quality of life | Questionnaire for the assessment of weight-related quality of life (Gewichtsbezogener Lebensqualitätsfragebogen (GW-LQ-KJ)) [27] | 0.83 |
| Motivation | Questionnaire for the assessment of intrinsic and extrinsic motivation [28] | - |
| Intelligence | Assessment of individual‘s intelligence (Wortschatztest, Zahlenfolgetest aus Grundintelligenztest Skala 2—CFT 20) [29] | - |
| Intrafamilial conflicts | Questionnaire for the assessment of intrafamilial conflicts (Familienklimaskalen (FKS)) [30] | 0.60–0.73 |
| Self-efficacy | Assessment of general self-efficacy (Allgemeine Selbstwirksamkeitserfahrung (SWE)) [31] | 0.82 |
| Resilience | Assessment of resilience (Resilienzskala (RS-11)) [32] | 0.76 |
| Sense of coherence | Children’s sense of coherence scale (CSOC) [33] | 0.64 |
| Stress-management | Questionnaire for the assessment of stress and its management (Fragebogen zur Erhebung von Streßerleben und Streßbewältigung im Kindesalter (SSK)) [34] | 0.77–0.92 |
| Social support | Berliner social support Scale (BSSS) [35] | 0.60–0.87 |
| Actual body shape | Figures of gender-specific body shape | - |