Table 2 Overview of the questionnaire instruments according to the thematic modules of the STARKIDS intervention

Quality of Life Questionnaire for children (KINDL^R), with obesity module

Original title: Fragebogen zur Erfassung der gesundheitsbezogenen Lebensqualität bei Kindern und Jugendlichen (KINDL^R) [23, 25,26,27]

24 plus 16 (obesity module)

Physical well-being, psychological well-being, self-esteem, family, friends, functioning in school/kindergarten

Cronbach’s a = .85

Convergent validity: parent report: r = .44–.63; child report: r = .33–.59 correlation with SDQ

Parent (child)

Adolescent (self)

University of Rhode Island Change Assessment (URICA-S) [28]

16

Precontemplation, contemplation, action, maintenance

Cronbach’s a = .61–.84

n/a

Adolescent (self)

Parent Perspective University of Rhode Island Change Assessment -Short (PURICA-S) [24]

16

Precontemplation, contemplation, action, maintenance

Cronbach’s a = .30–.84

Criteria validity good to very good (exception subscale precontemplation)

Parent (self)

Dutch Eating Behavior Questionnaire – Children (DEBQ-C) [29]

20

Restraint eating, emotional eating, external eating

Cronbach’s a = .74–.81

n/a

Parent (child)

Adolescent (self)

Rhythm of dietary intake

2

n/a

n/a

Parent (child)

Adolescent (self)

Knowledge about nutrition

10

Parent (self)

Adolescent (self)

Food Frequency Questionnaire (FFQ) – KiGGS version [30, 31]

114

n/a

r = .22–.69 correlation with DISHES nutrition interview

Parent (child)

Adolescent (self)

MoMo-Physical-Activity-Questionnaire

Original title: Aktivitätsfragebogen des Motorik-Moduls (MoMo-AFB, selected items) [32]

20

Intraclass correlation (ICC): r = .68

r = .29 correlation with accelerometer data

Parent (child)

Adolescent (self)

Physical Activity, Exercise, and Sport Questionnaire

Original title: Bewegungs- und Sportaktivität Fragebogen (BSA-F) [33]

10

Sports activity and physical activity

n/a

r = .32 with VO₂max

Parent (self)

Physical Activity Enjoyment Scale (PACES) [34]

16

Cronbach’s a = .89–.93

r = .42 correlation with physical activity diary

Parent (child)

Adolescent (self)

Self-concordance of sport- and exercise-related goals scale

Original title: Sport- und Bewegungsbezogene Selbstkonkordanz Skala (SSK) [35]

12

Intrinsic, identified, introjected and extrinsic modes of motivation

Cronbach’s a = .70–.82

r = .25–.38 correlation with physical activity

Parent (child)

Adolescent (self)

Basic Psychological Needs Questionnaire

Original title: Fragebogen zu Psychologischen Grundbedürfnissen

9

Autonomy, relatedness, competence

n/a

n/a

Parent (child)

Adolescent (self)

Exercise-related Support - Family

Original title: Sportbezogene Unterstützung aus der Familie (SU-F) [36]

6

Cronbach’s a = .85

n/a

Parent (child)

Adolescent (self)

Exercise-related Support - Friends

Original title: Sportbezogene Unterstützung von Freunden und Bekannten (SU-B) [36]

5

Cronbach’s a = .89

n/a

Parent (child)

Adolescent (self)

Barriers to physical activity

4

n/a

n/a

Parent (child)

Adolescent (self)

Bernese Motive and Goal Inventory

Original title: Berner Motiv- und Zielinventar (BMZI) [37]

26

Contact, competition/performance, distraction/catharsis, body/appearance, health, fitness, esthetics, and risk/challenge

Test-retest: .62–.83

Discriminant validity for acceptable

Parent (child)

Adolescent (self)

Parental mediation [38,39,40,41,42]

51

Active parental mediation, restrictive parental mediation, social co-viewing/co-use, supervision, concept-oriented family consumer communication, socio-oriented family consumer communication

Cronbach’s a = .75–.94

n/a

Parent (self)

Attitudes towards advertising [38, 43]

7

Cronbach’s a = .80

n/a

Parent (self)

Parent-Child Conflict [42, 44]

3

Cronbach’s a = .69

n/a

Parent (self)

Duration of media consumption

2

n/a

n/a

Parent (child)

Adolescent (self)

Strength and Difficulties Questionnaire (SDQ) [45, 46]

25

Emotional problems, striking behaviors, hyperactivity, troubles with peers, pro-social behaviors

Cronbach’s a = .55–.77 (self-evaluation)

n/a

Parent (child)

Adolescent (self)

Family climate (items of the iFamily study) [47,48,49]

8

Cronbach’s a = .61–.83

n/a

Parent (self)

Adolescent (self)

Shared activities (items of the iFamily study) [47, 49]

6

n/a

n/a

Parent (self)

Adolescent (self)

Sleep (items of the KiGGS study) [50]

4

n/a

n/a

Parent (child)

Adolescent (self)

Eating Disorder Examination Questionnaire 8 (EDEQ-8) [51]

8

Cronbach’s a =.93

r = .75 correlation with EAT-13

Parent (self)

Child version of the Eating Disorder Examination Questionnaire 8 (ChEDEQ-8) [52]

8

Cronbach’s a = .89

r = -?.65 correlation with body esteem scale

Adolescent (self)

Eating Disorder Inventory (EDI-2), subscale body dissatisfaction [53,54,55]

9

Only one scale used (body dissatisfaction)

Cronbach’s a = .84–.89

r_tt = .89/.94 (subscale)

r = .35 correlation with Beck Depression Inventory (subscale)

Parent (self)

Eating behaviors inventory – child, subscale dissatisfaction with body

Original title: Inventar zum Essverhalten und Gewichtsproblemen – Kind (IEG-K) [56]

Only one scale used (body dissatisfaction)

Cronbach’s a = .88 (subscale)

n/a

Adolescent (self)

Weight Bias Internalization Scale (WBIS) [57, 58]

11

Cronbach’s a = .87

r_tt = .88 (8 weeks)

r = .2 for BMI-SDS

r = -?.7 for self-esteem

r = -?.77 for HRQoL (weight),

acceptable construct validity in CFA

Adolescent (self)

Modified Weight Self Stigma Questionnaire (WSSQ) [59]

13

Modification of original scale to assess stigma by association

Cronbach’s a = .87 for original scale

r = -?.47 for HRQoL (weight)

Parent (self/child)

Body Image Avatars [60, 61]

3

These ratings have never been used before, for similar 2D avatars, a sample with female adult participants found r_tt = .88–.90 (5 weeks)

Rating corresponds with actual BMI: r = .89

Parent (child)

Adolescent (self)

Parenting Self-efficacy questionnaire

Original title: Fragebogen zur Selbstwirksamkeit in der Erziehung (FSW) [62]

9

Cronbach’s a =.78/.79

r = .63/.64 with parent behavior in risk situations

Parent (self)

Self-efficacy scale

Original title: Skala zur Allgemeinen Selbstwirksamkeitserwartung (SWE) [63, 64]

10

Cronbach’s a =.78–.79

n/a

Adolescent (self)

Perceived Stress Questionnaire-20 (PSQ-20) [65]

20

Worries, tension, joy, demands

Cronbach’s a =.80–.86

r = -?.58 correlation with WHOQOL-Bref (global)

Parent (self)

Systemic Clinical Outcome and Routine Evaluation-15 (SCORE-15) [66]

15

Cronbach’s a = .89

Convergent validity shown by correlation with various measures

Parent (self)

Adolescent (self)

Mannheimer Modul RV (MRV), adaptation for STARKIDS

31

n/a

n/a

Parent (child)

Adolescent (self)