Chatbot Intervention to Reduce Common Digital Addictions, Sedentary Behaviors and Mental Distress Among Adolescents

IGD symptoms are assessed using the Nine-Item Internet Gaming Disorder Scale-Short Form (IGDS9-SF) consists of nine questions that assess IGD symptoms, including preoccupation, tolerance, withdrawal, unsuccessful attempts to limit gaming, deception or lies about gaming, loss of interest in other activities, use despite knowledge of harm, use for escape or relief of negative mood, and harm. The response options for each item include "yes=1" and "no=0". The overall score of the scale ranges from 0 to 9, with a higher score implying a higher level of IGD symptoms. Participants with score ≥ 5 will be classified as having probable IGD.

SMA is defined as excessive use of social media with the addictive symptoms like mood modification, salience, tolerance, withdrawal symptoms, conflict, and relapse. The symptoms of SMA will be measured by the 6-item Bergen Social Media Addiction Scale (BSMAS) based on the six core components of addictive behaviors, including cognitive salience, tolerance, mood modification, difficulty in regulating use, withdrawal, and interference with role performance. The items are rated using a Likert type scale ranging between 1 (very rarely) and 5 (very often). A higher sum score in the BSMAS indicates a greater likelihood of being at risk of developing social media addiction. A cut-off score over 19 indicates probable SMA.

Composite outcome of IGD score and SMA score: we define a simple composite as the sum of the two outcomes. Because each outcome measure uses a different scale and has different statistical properties, we will standardize the two variables (i.e., scores of IGD and SMA) first, and then combine the two standardized scores of the outcomes into a composite.

Sedentary behavior is defined as any waking behavior such as sitting or leaning with an energy expenditure of 1.5 metabolic equivalent task (MET) or less. Sedentary lifestyles will be measured by the 10-item sedentary lifestyles questionnaire (SLQ) which has been used in Chinese school children. Subjects will report the average daily time spent (hours) during the weekdays and weekends in the following activities: Using smartphone or tablet PC for learning/doing paper homework or reading or writing/ sedentary leisure time without time for screen leisure. Average number of daily hours will be calculated as (total sedentary weekday hours × 5 + total sedentary weekend hours × 2) ÷ 7.

The American Academy of Pediatrics has recommended that time allotted to Internet gaming or the total amount of entertainment screen time in general (e.g., using social media platforms/social networking sites, watching TV/videos) should be <1 to 2 hours per day for children and adolescents given the significant health consequences of excessive Internet gaming and screen time. Thus, participants who report the total amount of entertainment screen time with two or more hours per day will be classified as excessive screen time cases and positive cases in our school-based screening.

Quality of life will be measured by the EQ-5D-Y scale (Y for youth). The EQ-5D-Y uses a similar 5-dimenional descriptive system with the EQ-5D but child-friendly wording, referring to mobility ('walking about'), self-care ('looking after myself'), usual activities ('doing usual activities'), pain and discomfort ('having pain or discomfort'), and anxiety and depression ('feeling worried, sad or unhappy'). Each dimension includes one item which has three functioning levels: no problem, some problems, and a lot of problems. The EQ-5D-Y also includes an easily understandable modification of the vertical, graduated Visual Analogue Scale (VAS) of EQ-5D, where the respondent rates his or her overall health status on a scale from 0 to 100 with 0 representing the worst and 100 the best health state the individual can imagine.

Mental distress is defined as a collection of mental problems that may not fall into standard diagnostic criteria and are characterized by symptoms of sleeplessness, depression, anxiety, exhaustion, irritability, poor memory, difficulty in concentrating, and somatic complaints. The Chinese K6 questionnaire comprises six questions that ask respondents to rate how frequently they have felt 'nervous', 'hopeless', 'restless or fidgety', 'so depressed that nothing could cheer you up', 'that everything was an effort', and 'worthless' during the past 30 days. Response options included 'none of the time' (0), 'a little of the time' (1), 'some of the time' (2), 'most of the time' (3), and 'all of the time' (4). The range of score for K6 was thus from 0 to 24.

eHealth literacy is defined as the ability of individuals to seek, find, understand, and appraise health information from electronic sources and apply such information to addressing or solving a health problem. eHealth literacy will be assessed by the 8-item eHealth Literacy Scale (eHEAL), which was validated in Chinese student population. The sample items include 'I know how to find helpful resources on the internet' and 'I know how to use the internet to answer my questions about health'. Ratings were made on 5-point Likert scales, ranging from 1= strongly disagree to 5 = strongly agree, with higher scores indicating a higher level of eHealth literacy.

Autonomy involves feeling a sense of personal agency and volition such that one's behavior is perceived to emanate from an internal locus of causality. To assess autonomy to reduce dependence on Internet gaming/social media, the subscale of the Psychological Need Satisfaction in Exercise Questionnaire (PNS-A) will be adapted and used. The Chinese version was demonstrated to have good psychometric properties. The scale includes six items measuring psychological need fulfillment of autonomy. Items are rated on a 6-point Likert scale, ranging from 1 (false) to 6 (true). Total scores range from 6 to 36, with higher scores being indicative of higher degrees of autonomy.

Competence refers to interacting effectively with one's environment while mastering challenging tasks. The 6-item competence subscale of PNS (PNS-C) will be used to assess competence to reduce dependence on Internet gaming/social media. Total scores range from 6 to 36, with higher scores being indicative of higher degrees of autonomy or competence.