Background and aims: The literature has proposed two types of problematic smartphone/internet use: generalized problematic use and specific problematic use. However, longitudinal findings on the associations between the two types of problematic use and psychological distress are lacking among East-Asians. The present study examined temporal associations between both generalized and specific problematic use of the smartphone/internet, and psychological distress.Methods: Hong Kong University students (N = 308; 100 males; mean age = 23.75 years; SD ± 5.15) were recruited with follow-ups at three, six, and nine months after baseline assessment. All participants completed the Smartphone Application-Based Addiction Scale (for generalized problematic smartphone/internet use), the Bergen Social Media Addiction Scale (for specific problematic smartphone/internet use), and the Hospital Anxiety and Depression Scale (for psychological distress) in each assessment. Latent growth modeling (LGM) was constructed to understand temporal associations between generalized/specific problematic use and psychological distress.Results: The LGM suggested that the intercept of generalized problematic use was significantly associated with the intercept of psychological distress (standardized coefficient [β] = 0.32; P < 0.01). The growth of generalized problematic use was significantly associated with the growth of psychological distress (β = 0.51; P < 0.01). Moreover, the intercept of specific problematic use was significantly associated with the intercept of psychological distress (β = 0.28; P < 0.01) and the growth of psychological distress (β = 0.37; P < 0.01).Conclusion: The initial level of problematic use of smartphone/internet increased the psychological distress among university students. Helping young adults address problematic use of the smartphone/internet may prevent psychological distress.

Background and aims: Due to the rapid spread of the novel coronavirus disease 2019 (COVID-19), policies based on the nature of “spatial distancing” have been implemented and have resulted in school suspensions and online learning among schoolchildren. In order to examine the impact of such policies on schoolchildren, the aims of the present study were to (i) assess changes in the level of engagement in three internet-related activities (smartphone use, social media use, and gaming) before and during the COVID-19 outbreak, including prolonged and problematic engagement in these activities; (ii) investigate the differences of psychological distress before and after COVID-19 outbreak; and (iii) to use structural equation modeling to investigate the mediating roles of problematic internet-related behaviors in the causal relationships of psychological distress and time spent on internet-related activities.Methods: Self-report measures were used to assess internet-related activities and psychological distress. Time spent on internet-related activities, problematic use of internet-related activities, and psychological distress were collected from primary school students (N = 535; 265 boys; M age = 10.32 years [SD = 0.84]). The data were first collected before the COVID-19 outbreak (i.e., early November 2019) and then collected again during the school suspension due to COVID-19 outbreak (i.e., end of March 2020) for comparisons of changes.Results: Schoolchildren spent significantly more time on the smartphone (increased 1.02 h daily; P < 0.001) and social media (increased 0.73 h daily; P < 0.001) but not gaming (increased 0.14 h daily; P = 0.07) during the school suspension compared to the baseline. Schoolchildren who increased by 15 or 30 min daily on internet-related activities showed an increased level of psychological distress. The association between problematic use of social media and psychological distress was stronger during the school suspension (β = 0.584) than at the baseline (β = 0.451; P < 0.001).Conclusion: Increased problematic use of internet-related activities among schoolchildren was associated with greater psychological distress. Parents should therefore monitor internet-related activities and psychological distress of their children to support their mental health.

Objective: The Theory of Planned Behavior (TPB) is one of the most robust models in explaining health-related behavior. In this study, we tested the extended TPB to predict university students’ intentions to uptake COVID-19 vaccination. Methods: An online cross-sectional survey was developed to investigate students’ intention to uptake the COVID-19 vaccine based on the components of the TPB (i.e., attitude, subjective norms, and perceived behavioral control) and extended components (i.e., knowledge about COVID-19, risk perception of COVID-19, and past influenza vaccination behavior). Non-probability sampling was used to collect data from 3145 students from 43 universities in mainland China in January 2021. Structural equation modeling (SEM) was applied to examine the proposed model. Enrolled students were relatively young (mean age = 20.80 years; SD = 2.09), half of them are female (50.2%), and most of them were studying in undergraduate programs (n = 3026; 96.2%). Results: The results showed that students’ knowledge of the COVID-19 vaccine and risk perception of COVID-19 positively influenced their attitude toward the uptake of a COVID-19 vaccine. Also, students’ attitude toward COVID-19 vaccination uptake and their past influenza vaccination uptake behaviors were positively associated with the intention to uptake COVID-19 vaccination. Subjective norm and perceived behavioral control were not significant predictors for the intention to uptake COVID-19 vaccination (R² = 0.49). Conclusions: The present study demonstrated that the extended TPB appears to be an efficient model with the focus on attitude, knowledge, risk perception, and past influenza vaccination uptake behaviors in explaining students’ intention for COVID-19 vaccination.