Table 1

Measurement tools in each wave

Categories	Measures		Wave
Categories	Measures	Source	T1	T2	T3	T4
Exposure variables	Exposure time to internet, smartphone and online game	Student/parent	√	√	√	√
	Internet, smartphone and online game using behaviours	Student	√	√	√	√
Diagnosis	IAT	Student	√
	K-scale	Student	√
	IGUESS	Student	√	√	√	√
	SR-IGD	Student	√		√	√
	SAS-SV	Student	√	√	√	√
Psychiatric comorbidities	CDI	Student	√	√	√	√
	TAIC	Student	√	√	√	√
	K-ARS	Parent	√
	DISC-IV	Parent	√
	Suicidality	Student	√	√	√	√
	PHQ-9	Parent	√
Personal factors	Rosenberg’s Self-Esteem Scale	Student	√
	Self-control scale	Student	√
	AQ	Student	√	√	√	√
	Demographic information	Student/parent	√
	Academic achievement	Student/parent	√	√	√	√
Environmental factors	School policy on having smartphone use in school	Student	√	√	√	√
	PACI	Student	√
	Marriage satisfaction	Parent	√
	IPPA-R	Student	√
	Perceived parenting competence	Parent	√
	Online gaming rule in home	Parent	√	√	√	√
Social factors	Social network	Student	√
	Bullying scale	Student	√
	SSAS	Student	√
Health consequences	Physical health	Student/parent	√
	Mental health	Student	√

AQ, Aggression Questionnaire; CDI, Children’s Depression Inventory; DISC-IV, Diagnostic Interview Schedule for Children, Version IV; IAT, Internet Addiction Test; IGUESS, Internet Game Use-Elicited Symptom Screen; IPPA-R, Revised Inventory of Parent and Peer Attachment; K-ARS, Korean version of the ADHD Rating Scale; K-scale, Korean Scale for Internet Addiction; PHQ-9, Patient Health Questionnaire; PACI, Parent-Adolescent Communication Inventory; SAS-SV, Short version of the Smartphone Addiction Scale; SR-IGD, Self-reported version of structured clinical interview for internet gaming disorder; SSAS, Social Support Appraisals Scale: Child’s Subjective Appraisal of Family, Peer and Teacher Support; TAIC, Trait Anxiety Inventory for Children.