Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000940471
Ethics application status
Approved
Date submitted
12/08/2025
Date registered
29/08/2025
Date last updated
29/08/2025
Date data sharing statement initially provided
29/08/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
The Vibe Up Precision - Pilot Trial: Using Smartphone and Smartwatch Data to Predict Response to Smartphone-Based Interventions Among Australian University Students With Symptoms of Psychological Distress
Scientific title
The Vibe Up Precision - Pilot Trial: A Pilot Randomised Controlled Trial of Digital Phenotyping Predictors of Response to Smartphone App-Delivered Self-Care Strategies for Psychological Distress in Australian University Students
Secondary ID [1] 314860 0
Nil Known
Universal Trial Number (UTN)
U1111-1326-7681
Trial acronym
Not applicable
Linked study record
This study uses the same four interventions as a previous trial ACTRN12621001223820

Health condition
Health condition(s) or problem(s) studied:
Psychological distress 338526 0
Condition category
Condition code
Mental Health 334830 334830 0 0
Depression
Mental Health 334831 334831 0 0
Anxiety

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
GENERAL DESIGN
This is a 4-arm pilot randomised controlled trial of 8 weeks duration designed to assess whether digital phenotyping markers predict response to brief smartphone-delivered interventions for psychological distress among university students in Australia.

Each participant will undergo an initial 2-week pre-intervention period involving daily Ecological Momentary Assessment (EMA; Weeks 1 and 2), then will be randomly assigned to one of four trial arms (mindfulness, physical activity, sleep hygiene, control) that involve receiving access to their assigned intervention (or control) that they will complete for 2 weeks (Weeks 3 and Week 4), followed by continued access to their assigned intervention (or control) over a 4-week follow-up period (Weeks 5 to 8).

PRE-INTERVENTION EMA PERIOD
During the 2-week pre-intervention EMA period, participants will complete EMA twice per day. The EMA will run on a signal-contingent protocol consisting of two daily random prompts to the participant generated by a custom-built smartphone application at a random time within two windows: morning (08:00-10:00) and evening (19:00-21:00). Participants will have up to 60 minutes to respond to the prompt, with a reminder sent after 30 minutes if the prompt has not been responded to.

Each EMA measurement will consist of an initial question asking if the participant is experiencing any of the emotions drawn from an extended Short Form (12 item) version of the internationally reliable form of the Positive and Negative Affect Schedule (I-PANAS). If any emotions are selected on this first question, the participant will be asked two follow-up questions exploring behavioural intentions as a result of measured feelings, intended to assess coping styles.

INTERVENTION PERIOD
At the end of Week 2, participants will be randomised to receive one of three interventions or a control for 2 weeks. These interventions consist of three active interventions (mindfulness, sleep hygiene, physical activity) and an EMA control intervention. All interventions are brief, app-delivered, self-guided digital informational/behavioural interventions. Each intervention is entirely separate but consists of a combination of brief modular information covering key concepts, delivered via infographics, as well as structured activities (e.g., practicing mindfulness using a guided audio). All four interventions have been used recently in the Vibe Up AI-enhanced adaptive trial (trial ID ACTRN12621001223820). A summary of the intervention content is as follows:

ARM 1: MINDFULNESS
The Mindfulness intervention starts with an introductory video (3 minutes), followed by five guided mindfulness practices delivered as audio recordings (3-5 minutes in length). The content of the modules is as follows:
a) Introductory video: Explains what mindfulness is and the benefits; defines formal vs. informal mindfulness practice; how to tune into the five senses and bring mindful awareness to daily activities; and how to reduce judgment and increase self-compassion.
b) Module 1: Guided mindfulness practice based on mindful awareness of breathing (audio with male/female voice options)
c) Module 2: Guided mindfulness practice teaching non-judgment towards thoughts, using 'leaves on a stream' imagery (audio with male/female voice options)
d) Module 3: Guided mindfulness practice based on mindful awareness of body sensations and releasing of muscle tension (audio with male/female voice options)
e) Module 4: Guided mindfulness practice encouraging the use of all five senses to bring curiosity to everyday activities (audio with male/female voice options)
f) Module 5: Guided mindfulness practice blending awareness of surrounding environment and bodily sensations (audio with male/female voice options)
The modules are made available to participants as follows:
• The introductory video is available to participants immediately after allocation to the intervention.
• The first mindfulness audio guide becomes available immediately after the introductory video has been completed.
• The subsequent mindfulness audio guides are sequentially released, at one day intervals (regardless of participant engagement).
Expected effort: A minimum of one mindfulness audio completed daily at participants' convenience. All modules completed at least once by the end of the intervention period. Participants are also encouraged to practice bringing mindful awareness to activities throughout their day (‘informal’ mindfulness).

ARM 2: PHYSICAL ACTIVITY
The Physical Activity intervention starts with an introductory infographic explaining the benefits of physical activity for cognition, mental health and physical health, Australian guidelines for physical activity, how to set realistic goals and benefits of even small change, and tips to foster enjoyment of physical activity (e.g., being social, settings goals, tracking progress). It then prompts participants each day to choose a goal to increase their physical activity that day. An evidence-based seven-minute high-intensity circuit training (HICT) protocol is provided as one option for increasing physical activity. Other examples of exercises that are suggested within the intervention are walking, social sport, gardening, yoga, bike riding or dancing.
The modules are made available to participants as follows:
• An introductory infographic is available to participants immediately after allocation to the intervention.
• The Daily goal setting and 7-minute workout becomes available immediately after a participant has completed the introductory infographic.
Expected effort: Physical activity completed daily at participants' convenience, including a 7-minute work out three times weekly or, alternatively, increasing steps by 10% weekly.

ARM 3: SLEEP HYGIENE
The Sleep Hygiene intervention centres around four brief, sequential modules covering key sleep hygiene concepts, which are delivered via infographics. Each module takes up to five minutes to read. The content of the modules is as follows:
a) Module 1: Why we sleep? Covers the recommended hours of sleep per night, the impact of lack of sleep on cognition and emotion, benefits of sleep for mental health and physical health, and an introduction to sleep hygiene.
b) Module 2: Sleep habits. covers establishment of regular bedtime and wake time, eliminating or limiting naps, establishing a wind down routine.
c) Module 3: Sleep environment. Covers how to reduce light, noise and temperature disturbance, and ensuring bedding is comfortable; limiting the use of bed to sleep and sex; the impact of electronic devices on sleep; get out of bed when unable to sleep for 20 minutes or more.
d) Module 4: Reducing caffeine, alcohol and nicotine intake close to bedtime; eating a healthy diet; increasing physical activity and avoiding exercise close to bedtime.
The modules are made available to participants as follows:
• Module 1 is available to participants immediately after allocation to the intervention.
• Module 2 becomes available immediately after a participant has completed Module 1.
• Module 3 becomes available two days after Module 2 is made available (regardless of participant engagement).
• Module 4 becomes available two days after Module 3 is made available (regardless of participant engagement).
Expected effort: All modules completed at least once by the end of the intervention period. Participants are instructed to choose one strategy from each of Module 2 – 4 and implement it daily (total of 3 strategies by end of intervention period).

ASSESSMENT OF ADHERENCE
Throughout the intervention period, participants are asked to log their engagement with the intervention daily via an in-app logging question. For those assigned to the physical activity intervention, they are asked to log how many minutes of physical activity they engaged in that day; for those assigned to the sleep hygiene intervention, they are asked to log how many hours of sleep they got that day; and for those assigned to the mindfulness intervention, they are asked to rate how many minutes of mindfulness practice they engaged in that day.

FOLLOW-UP PERIOD
All participants will continue to have access to their assigned intervention throughout a 4-week follow-up period (Weeks 5 to 8). They will be encouraged to practice implementing the skills learned in the intervention.
Intervention code [1] 331735 0
Lifestyle
Intervention code [2] 331736 0
Behaviour
Comparator / control treatment
EMA CONTROL
Participants randomised to the EMA control intervention will continue doing twice daily EMA during the intervention period, following the same protocol used for all participants during the 2-week pre-intervention EMA period.
Control group
Active

Outcomes
Primary outcome [1] 342462 0
Psychological distress
Timepoint [1] 342462 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [1] 450912 0
Level of physical activity
Timepoint [1] 450912 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [2] 450915 0
Sleep quality
Timepoint [2] 450915 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [3] 450916 0
Mindfulness
Timepoint [3] 450916 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [4] 450917 0
Depression
Timepoint [4] 450917 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [5] 450918 0
Anxiety
Timepoint [5] 450918 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [6] 450919 0
Anhedonia
Timepoint [6] 450919 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).
Secondary outcome [7] 450920 0
Amotivation
Timepoint [7] 450920 0
Baseline (Week 0), pre-intervention (Week 2), post-intervention (Week 4), follow-up (Week 8).

Eligibility
Key inclusion criteria
Inclusion criteria for participants taking part in this study include:
1. At least 18 years of age
2. Living in Australia for the duration of the trial
3. Enrolled at a higher education institution
4. Advanced, fluent or native English speaker
5. Owning an up-to-date smartphone with an active mobile number and internet access
6. Self-rated psychological distress score of 20 or higher on the Kessler 10-item Psychological Distress scale
7. Ability to attend an in-person onboarding session
8. Willing and able to wear a smartwatch 24/7 for 8 weeks
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Under the age of 18 years
2. High self-rated suicidal ideation on the Suicide Ideation Attributes Scale (scores greater than or equal to 21)
3. Self-reported psychosis or bipolar disorder
4. Previous participation in the current trial
5. Circumstances that would prevent adequate trial participation in the next 8 weeks (e.g., international travel)
6. Inability to safely undertake a physical activity intervention
7. Participants will be allowed to undertake other concurrent treatments but will be discouraged from starting new treatments while participating
8. Diagnosed with a physical or neurological condition that would interfere with wearing a smartwatch (e.g., severe skin condition, tremor disorder)

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
After completing the baseline questionnaires, pre-intervention EMA period and pre-intervention questionnaires, participants will be randomly allocated by the app to their intervention (or control) arm. The app will only reveal the allocated condition to participants after the EMA period and pre-intervention questionnaires are completed.

Allocation concealment will be guaranteed by preventing access by blinded study staff to the computer system holding randomisation information; and by breaking randomisation codes only once primary data analysis is complete.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computerised allocation will be performed automatically using a digital clinical trials platform called ‘Conductor’
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
GENERAL APPROACH
We will use mixed effects repeated-measures (MMRM) models for continuous outcomes, with intention-to-treat as the primary analysis set (all participants who start the study and who are randomised are analysed according to randomised arm). Models will include the relevant pre-intervention score as a predictor in all analyses). An unconstrained (unstructured) variance-covariance matrix will model within-individual dependencies. Transformation of scores may be undertaken to satisfy distributional assumptions and accommodate outliers. We will use a two-sided alpha=0.05.

MISSING DATA
The primary and key secondary MMRM analyses assume data are Missing At Random (MAR). Sensitivity analyses will include pattern-mixture and/or delta-adjustment models to assess robustness to violations of MAR.

PRIMARY ENDPOINT
The primary endpoint is post-intervention DASS-21 total. We will fit an MMRM with fixed effects for treatment group, time (pre-intervention, post-intervention), treatment×time interaction, baseline DASS-21, and digital phenotyping-related stratification factors; an unstructured covariance will be used. The primary contrast is the adjusted mean difference (each intervention vs control) at post-intervention with 95% CI. Supportive analyses will include percent change, responder status (50% or greater reduction) and remitter status (symptoms in the nil/minimal symptoms range as per the DASS-21 manual) modelled using generalised linear models (logistic for responder/remitter status), adjusted for baseline. We will also examine whether treatment effects are moderated by digital phenotyping-derived subgroup (further details below) by entering digital phenotyping subgroup×time (for prognostic effects) and digital phenotyping subgroup×treatmen×time (for prescriptive effects) interaction terms.

SECONDARY OUTCOMES
For key secondary outcomes mindfulness (single-item mindfulness questionnaire), sleep quality (PSQI), and physical activity (PAVS), we will use MMRM with the same structure as above, including the relevant baseline measure as a covariate. Between-group differences (intervention vs control) at post-intervention will be estimated with 95% CIs.

SUPPORTING SECONDARY OUTCOMES
For the supportive secondary outcomes PHQ-9, GAD-7, SHAPS, and the AMI, we will use MMRM as above (baseline score as covariate), reporting adjusted mean differences with 95% CIs.

DIGITAL PHENOTYPING: Preprocessing and derived features
All smartphone/smartwatch data (including 50 Hz tri-axial accelerometry and Garmin summaries: steps, heart rate, stress, sleep, etc.) will be exported weekly. The custom pipeline will (i) remove implausible/extreme values, (ii) downsample where necessary, (iii) segment into fixed windows (e.g., 5 min), (iv) extract movement/behaviour features (e.g., mean intensity, stillness bouts), and (v) aggregate to participant-level summaries for analysis.

DIGITAL PHENOTYPING: Subgroup derivation and moderation analysis
Baseline digital phenotyping features (e.g., activity regularity, mobility patterns, sleep metrics) will be used to derive behavioural subgroups. We will use an unsupervised clustering algorithm (e.g., k-means or model-based clustering) on appropriately scaled and standardised features, with the number of clusters determined via internal validation metrics (e.g., silhouette score, gap statistic). The resulting categorical subgrouping variable will be entered into an MMRM as a treatment effect moderator by including all two- and three-way interaction terms (treatment × time × subgroup). Models will adjust for baseline values of the outcome and relevant covariates. Significant treatment × subgroup interactions will be interpreted as evidence of treatment effect heterogeneity by digital phenotyping profile.

DIGITAL PHENOTYPING: Additional analyses
1. Prediction models (pre-intervention features). Multivariable models (elastic-net, support vector machines, random forests) will predict symptom change and treatment response (=50% DASS-21 reduction). Performance will be estimated via nested cross-validation; the primary metric is AUC. SHAP values will summarise feature importance.
2. Mediation. For selected features (e.g., step counts, sleep metrics), we will test indirect effects of intervention, change in feature, and change in DASS-21 using non-parametric bootstrap (10,000 samples) with 95% CIs, adjusting for relevant covariates. Each mediator will be analysed separately.
3. Concordance (phone vs smartwatch). For overlapping metrics (e.g., steps, movement intensity), we will compute paired observations and assess Pearson correlations, stratified by participant and feature type, to characterise agreement.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
15/09/2025
Actual
Date of last participant enrolment
Anticipated
14/10/2025
Actual
Date of last data collection
Anticipated
15/12/2025
Actual
Sample size
Target
120
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 319418 0
Charities/Societies/Foundations
Name [1] 319418 0
Wellcome Trust
Country [1] 319418 0
United Kingdom
Funding source category [2] 319688 0
Charities/Societies/Foundations
Name [2] 319688 0
Anika Foundation
Country [2] 319688 0
Australia
Funding source category [3] 319689 0
Government body
Name [3] 319689 0
National Health and Medical Research Counil
Country [3] 319689 0
Australia
Primary sponsor type
University
Name
University of New South Wales, Sydney
Address
Country
Australia
Secondary sponsor category [1] 322193 0
None
Name [1] 322193 0
Address [1] 322193 0
Country [1] 322193 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 317989 0
The University of New South Wales Committee C
Ethics committee address [1] 317989 0
Ethics committee country [1] 317989 0
Australia
Date submitted for ethics approval [1] 317989 0
30/06/2025
Approval date [1] 317989 0
01/08/2025
Ethics approval number [1] 317989 0
iRECS9459

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 142798 0
A/Prof Alexis Whitton
Address 142798 0
Black Dog Institute, Hospital Road, Randwick, NSW, 2031
Country 142798 0
Australia
Phone 142798 0
+61 02 9065 9046
Fax 142798 0
Email 142798 0
[email protected]
Contact person for public queries
Name 142799 0
Alexis Whitton
Address 142799 0
Black Dog Institute, Hospital Road, Randwick, NSW, 2031
Country 142799 0
Australia
Phone 142799 0
+61 02 9065 9046
Fax 142799 0
Email 142799 0
[email protected]
Contact person for scientific queries
Name 142800 0
Alexis Whitton
Address 142800 0
Black Dog Institute, Hospital Road, Randwick, NSW, 2031
Country 142800 0
Australia
Phone 142800 0
+61 02 9065 9046
Fax 142800 0
Email 142800 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No
No IPD sharing reason/comment: This will not be available as per the conditions of our ethical approval, however we plan to run a full-scale RCT following completion of this pilot trial, and plan to make that data available to the research community for further research.



What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.