The Future Proofing Study: Design, methods and baseline characteristics of a prospective cohort study of the mental health of Australian adolescents

Self‐report measures		Baseline	Post (Stage I)	6 months	12 months	Post (Stage II) ^a	24 months	36 months	48 months	60 months
Participant characteristics
Demographics	Age, sex at birth, residential location, country of birth, language spoken most at home, perceived socioeconomic status, household makeup, Aboriginal and/or Torres Strait Islander identity	✓	‐	‐	‐	‐	‐	‐	‐	‐
Height and weight	Height (cm), weight (kg)	✓	‐	‐	✓	‐	✓	✓	✓	✓
Gender identity	Current gender identity	✓	‐	‐	✓	‐	✓	✓	✓	✓
Sexuality	Sexual identity and attraction	✓	‐	‐	✓	‐	✓	✓	✓	✓
Primary and secondary outcome measures
Depression	Patient health questionnaire: Adolescent version (PHQ‐A)	✓	✓	✓	✓	✓	✓	✓	✓	✓
Psychological distress	Distress questionnaire 5 (DQ5)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Anxiety	Spence children's anxiety scale short form (CAS‐8) and CAS generalized anxiety and social phobia subscales	✓	✓	‐	✓	✓	✓	✓	✓	✓
Insomnia	Insomnia severity index (ISI)	✓	✓	‐	✓	✓	✓	✓	✓	✓
Suicidal ideation	Suicidal ideation attributes scale (SIDAS)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Additional outcome measures, potential mediating variables, risk factors
Diagnosed mental health condition	Reported diagnosed mental health condition	✓	✓	‐	✓	‐	‐	‐	✓	✓
Diagnosed disability	Reported diagnosed disability	✓	‐	‐	‐	‐	‐	‐	✓	‐
Disordered eating	Screen for disordered eating (SDE)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Sleep quality	Pittsburgh sleep quality index (PSQI)	✓	✓	‐	✓	✓	✓	✓	✓	✓
Internalizing and externalizing symptoms	Strengths and difficulties questionnaire (SDQ)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Wellbeing	Short‐form Warwick‐Edinburgh mental wellbeing scale (SWEMWBS)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Quality of life	Child health utility 9D (CHU‐9D)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Self‐harm	Self‐harm questionnaire	✓	✓	‐	✓	‐	✓	✓	✓	✓
Suicidal behavior	Youth risk behavior survey (YRBS)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Psychotic‐like symptoms	Adolescent psychotic‐like symptom screener (APSS)	✓	✓	‐	✓	‐	✓	✓	✓	✓
Alcohol use	Age of onset and frequency of alcohol use	✓	✓	‐	✓	‐	✓	✓	✓	✓
Other substance use	Use of cannabis, tobacco, and other substances	✓	✓	‐	✓	‐	✓	✓	✓	✓
Hospital admissions	Reported hospital admissions for physical and mental health	✓	✓	‐	✓	‐	✓	✓	✓	✓
Childhood trauma	Behavioral risk factor surveillance system ‐ Adverse childhood experience (BRFSS‐ACE)	✓	‐	‐	‐	‐	‐	‐	✓	‐
Stressful life events	Exposure to stressful life events	‐	‐	‐	✓	‐	✓	✓	✓	✓
Personality	Big five inventory‐10 (BFI‐10)	✓	‐	‐	‐	‐	‐	‐	‐	‐
Social support	Schuster social support scale (SSSS)	✓	✓	‐	✓	‐	✓	✓	✓	✓
School connectedness	Items from programme for international student assessment (PISA)	✓	✓	‐	✓	‐	✓	✓	✓	‐
School climate	School climate measure	✓	✓	‐	✓	‐	✓	✓	✓	‐
Bullying	Frequency and type of bullying	✓	✓	‐	✓	‐	✓	✓	✓	✓
Resilience	Connor‐Davidson resilience scale (CD‐RISC‐10)	‐	‐	‐	✓	‐	✓	✓	✓	✓
Screen time	Hours of recreational screen time per day	✓	✓	‐	✓	‐	✓	✓	✓	✓
Social media use	Maladaptive Facebook use survey (MFUS), adapted to apply to social media use more broadly	✓	✓	‐	✓	‐	✓	✓	✓	✓
Pubertal development	Menarche, voice breaking and Tanner stages	✓	‐	‐	✓	‐	✓	✓	✓	✓
Romantic relationships	Reported romantic relationships	✓	‐	‐	✓	‐	✓	✓	✓	✓
Sexual behavior	Reported sexual behavior	‐	‐	‐	‐	‐	✓	‐	✓	‐
COVID‐19 exposure	Experience of COVID‐19 pandemic and child traumatic stress questionnaire (CTSQ)	✓	✓	‐	✓	‐	✓	✓	‐	‐
Bushfire exposure	Bushfire exposure questionnaire (BEQ) and child traumatic stress questionnaire (CTSQ)	✓	‐	‐	✓	‐	✓	✓	✓	✓
Flood exposure	Exposure to Australian flood disaster in 2022	‐	‐	‐	✓	‐	✓	✓	‐	‐
Top three concerns	Current top three issues of concern	✓	✓	‐	✓	‐	✓	✓	✓	✓
Priorities for the future	Social and political issues of importance to young Australians	‐	‐	‐	✓	‐	✓	✓	✓	✓

School characteristics (imputed from ACARA schools database)		Baseline	Post (stage I)	6 months	12 months	Post (stage II) ^a	24 months	36 months	48 months	60 months
Location	State, local government area	✓	‐	‐	‐	‐	‐	‐	‐	‐
Remoteness	Accessibility and remoteness index of Australia (ARIA+)	✓	‐	‐	‐	‐	‐	‐	‐	‐
Sector and type	Government or non‐government, combined or secondary	✓	‐	‐	‐	‐	‐	‐	‐	‐
Size	Full time equivalent students, full time equivalent teaching staff	✓	‐	‐	‐	‐	‐	‐	‐	‐
Socio‐educational advantage	Index of community socio‐educational advantage (ICSEA)	✓	‐	‐	‐	‐	‐	‐	‐	‐

Smartphone‐collected data		Baseline	Post (stage I)	6 months	12 months	Post (stage II) ^a	24 months	36 months	48 months	60 months
Self‐rated mood	Ecological momentary mood rating on 5‐point scale	✓	✓	‐	✓	‐	✓	‐	‐	‐
Affective card sorting task	Wisconsin card sorting task, with/without affective distractors	✓	✓	‐	✓	‐	✓	‐	‐	‐
Affective backward span task	Digit span backwards, with/without affective distractors	✓	✓	‐	✓	‐	✓	‐	‐	‐
Typing task	Copying and free typing about every day and affective topics	✓	✓	‐	✓	‐	✓	‐	‐	‐
Voice task	Sentence narration, phonemes, recall and free speaking on provided topics	✓	✓	‐	✓	‐	✓	‐	‐	‐
Movement (opt‐in)	Accelerometery and gyroscope device sensor data	✓	✓	‐	✓	‐	✓	‐	‐	‐
Location (opt‐in)	GPS device sensor data	✓	✓	‐	✓	‐	✓	‐	‐	‐
Data linkage (opt‐in)
Birth and early development		Birth registrations, neonatal intensive care, perinatal care
Health service utilization		Admission to hospital and emergency department, ambulance use, mental health ambulatory care, use of health services under Medicare and Pharmaceutical Benefits Scheme
Physical health outcomes		Self‐harm and suicide attempt, cancer registry, notifiable conditions, death registrations
Educational outcomes		Standardized test results from school years 3, 5, 7, 9, 10 and 12

TABLE 1.