Advancing Adolescent Bedtime by MI and Text Reminders

Daily sleep diary for consecutive seven days. Sleep parameter estimated by daily sleep diary: total sleep time (TST) in hours

Sleep parameter estimated by actigraphy: total sleep time (TST) in hours

Sleep knowledge is measured by Sleep Knowledge Questionnaire. It consists of 25 items, ranging from -50 to 50 with higher score indicates better sleep knowledge

Paediatric Daytime Sleepiness Scale (PDSS) is an 8-item self-rated scale measuring daytime sleepiness, ranging in total scores from 0 to 32 with higher scores indicating more sleepiness.

KIDSCREEN-27 health questionnaire for children and young people for the measurement of quality of life by rating 27 items related to general health on a 5 point Likert scale.

There are five subscales on: physical well-being (possibly scored from 5 to 25), psychological well-being (possibly scored 7 to 35), autonomy & parents (possibly scored 7 to 35), peers & social support (possibly scored 4 to 20), and school environment (possibly scored 4 to 20). A grand total score can be calculated by summing up the five sub scores. In all cases, a higher score represents higher perceived well-being.

Adolescent Sleep Hygiene Scale (ASHS): It is a 28-item instrument used to assess how adolescent apply sleep hygiene practice. total score range from 28 to 168 with higher score indicates better sleep practice. The instrument assessed adolescent sleep practice in nine domains: physiological(5 items, score 5-30), cognitive(6 items, score: 6 to 36), emotional(3 items; score: 3-18), sleep environment(4 items; score: 4-24), daytime sleep(1 items; score 1-6), substance(2 items; score: 2 to 12), bedtime routine(1 items; score:1-6), sleep stability(4 items; score: 4 to 16) and bedroom sharing(2 items; score 2-12).

Hospital Anxiety and Depression Scale (HADS) is a self-assessed scale for detecting states of depression and anxiety. The depression subscale range in scores from 0 to 21, with higher scores indicating severer states of depression. Similarly, the anxiety subscale range in scores from 0-21 with higher scores indicating severer states of anxiety. No additional computation will be made with the two subscores.

Academic performance is evaluated by the difference in average grade point between baseline, 3 month and 6 month.

Go/No-go Task for assessing inhibitory ability. In Go/No-go Task, a higher error rate indicates lower inhibition control.

Digit Span Task for assessing working memory capacity. In Digit Span Task, a higher number of recalled digits indicates better working memory.

N-back Task for assessing working memory capacity and manipulation. In N-back Task, a d prime score will be calculated based on the signal detection theory, where a higher score indicates better working memory performance.

Balloon Analogue Risk Task for assessing risk-taking and decision-making. In Balloon Analogue Risk Task, a score will be calculated by averaging the number of pumps on unexploded blue balloons, where a higher score indicates more risk-taking and impulsive propensities.