Real-time phone program to improve screen-time self-regulation and well-being

Activating Metacognition in Daily Life: A Randomized Controlled Ecological Momentary Intervention to Improve Digital Self-Regulation and Well-Being

This project tests a phone-based program that asks young adults (18–25) to upload screen-time screenshots and do short reflections to see if that helps them manage recreational screen use and feel better.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 240 (estimated)
• Ages: 18 Years to 25 Years
• Sex: All
• Sponsor: The Hong Kong Polytechnic University (Academic / other)
• Locations: 1 site (Hong Kong, Select An Option…)
• Trial ID: NCT07511374 on ClinicalTrials.gov

What this trial studies

This randomized controlled trial delivers an ecological momentary intervention that combines behavioral self-monitoring (device screen-time screenshot uploads) with structured, brief reflection prompts delivered on participants' smartphones. Young adults aged 18–25 are randomized to receive the EMI or a comparison condition and complete daily diaries across the trial to capture metacognitive awareness, metacognitive regulation, recreational screen time, stress, and life satisfaction. The design integrates intensive longitudinal data with randomization to identify both overall effects and within-person mechanisms of change. Outcomes will test whether momentary self-monitoring plus reflection yields sustained changes in digital self-regulation and psychological well-being.

Who should consider this trial

Good fit: Ideal participants are 18–25-year-olds who own and regularly use a smartphone, report at least 3 hours/day recreational screen time on weekdays or 4 hours/day on weekends, can access and upload device screen-time screenshots, and are motivated to regulate their screen use while completing daily surveys.

Not a fit: People outside the 18–25 age range, those with low recreational screen use, those unable to provide device screenshots or unwilling to complete daily surveys, or those not motivated to change their screen use are unlikely to benefit.

Why it matters

Potential benefit: If successful, the program could help young adults build metacognitive skills that reduce recreational screen time and improve stress and life satisfaction.

How similar studies have performed: Prior ecological momentary and self-monitoring interventions for digital use and other health behaviors have shown modest success, but combining screenshot-based tracking with structured metacognitive reflection is relatively novel.

Eligibility criteria

Inclusion Criteria:

Participants must meet all of the following criteria:

1. Age between 18 and 25 years old.
2. Own and regularly use a smartphone.
3. Report an average daily recreational screen time of at least 3 hours on weekdays or 4 hours on weekends, based on self-report (Zablotsky et al., 2025).
4. Be able to access their device's built-in screen time tracking function (or equivalent system-level usage report) and upload screenshots when required.
5. Be willing and able to complete daily surveys throughout the full study period.
6. Indicate motivation to reduce or regulate their recreational screen use.

Exclusion Criteria:

1. Outside the age range of 18-25 years.
2. Do not own a smartphone or do not use it regularly.
3. Report average daily recreational screen time below 3 hours on weekdays and below 4 hours on weekends.
4. Are unable to access device-based screen time tracking functions or cannot provide valid screenshots when required.
5. Are unwilling or unable to complete daily surveys across the study period (e.g., anticipated non-compliance, scheduling constraints).
6. Do not express motivation to reduce or regulate their recreational screen use.

Where this trial is running

Hong Kong, Select An Option…

• The Hong Kong Polythechnic University — Hong Kong, Select An Option…, Hong Kong (Recruiting)

Study contacts

• Study coordinator: Shiyun Chen, PhD Candidate

Conditions Behavioral Self-monitoring and Metacognitive Reflection; self-regulation; metacognition-based intervention; reflection; digital ecological momentary intervention