This study investigates the prevalence of Internet addiction among adolescents with ASD and elucidates factors related to Internet addiction among adolescents with and without ASD.
Participants and design
Participants were adolescent outpatients at the Center for Child Health, Behavior and Development, Ehime University Hospital. This center is a specialized psychiatry outpatient clinic for children and adolescents where medical examinations are performed for almost 200 new patients annually. The study period was from January 2017 to December 2019, before the outbreak of the COVID-19 pandemic.
The inclusion criteria were as follows: Those 1) aged 12–15 years, equivalent to being enrolled in 7th–9th grade; 2) who visited the hospital for the first time during the study period; 3) who signed informed consent forms and whose parents provided informed assent forms for study participation; 4) who were diagnosed with ASD based on the Autism Diagnostic Observation Schedule-2, Autism Diagnostic Interview-Revised, and DSM-5 criteria (American Psychiatric Association, 2013).
The exclusion criteria were as follows: Those 1) unable to fully comprehend and respond to questionnaires because of moderate-to-severe intellectual disabilities or severe psychiatric disorders, such as schizophrenia and anorexia nervosa, as screened by psychiatrists; 2) who were diagnosed with depressive disorders or ADHD based on the DSM-5 criteria (American Psychiatric Association, 2013).
According to the eligibility criteria, 102 participants (equivalent, 51.0%) were included in this study (Fig. 1). Participants were divided into two separate groups: adolescents with ASD and those without ASD.
Participants completed the basic information questionnaire, Young's Internet Addiction Test (IAT) (Young, 1996), and the Quick Inventory of Depressive Symptomatology Self-Report (Rush et al., 2003) Japanese version (QIDS-J). Simultaneously, parents of participants responded to the Social Responsiveness Scale-2 (SRS-2) (Constantino & Gruber, 2012) and ADHD Rating Scale-IV (ADHD-RS) (Tani et al., 2010).
Basic Information Questionnaire
The basic information questionnaire included questions regarding sex, school grade, and usage of electronic devices, such as Television, Laptop, Computers, Tablets, Smartphones, and Video game consoles. Participants also responded to the question: “Are electronic devices freely accessible to you?” with “Yes” or “No.”
Internet Addiction Test
The IAT comprises 20 items and is calibrated with scores between 1 and 5, with total scores ranging from 20 to 100. Higher scores reflect a greater tendency toward addiction. Total scores ≥ 70 are classified as severe Internet addiction and between 40–69 as possible Internet addiction (Young, 1996). In this study, the Internet addiction group was classified as those obtaining an IAT score ≥ 50, while the non-Internet addiction group was classified as those obtaining IAT score ≤ 49. This classification was based on several previous studies that defined mild and severe Internet addiction with an IAT score ≥ 50 (Malak et al., 2017; Tateno et al., 2018). In the present study sample (n = 102), the Cronbach’s α coefficient was 0.93.
Quick Inventory of Depressive Symptomatology Self-Report-Japanese version
We used the QIDS-J to evaluate the severity of depression in each patient. The total score ranges from 0 to 27, with higher scores indicating a higher severity of depression. Individual scores are interpreted as 0–5 (none), 6–10 (mild severity), 11–15 (moderate severity), 16–20 (severe), and 21–27 (very severe) (Rush et al., 2003). Thus, a cut-off score of 11 is considered to indicate moderate or severe levels of depression. Both the validity and reliability of the QIDS-J have been established previously (Trivedi et al., 2004). In the present study sample (n = 102), Cronbach’s α coefficient was 0.85.
Social Responsiveness Scale-2
The SRS-2 is a 65-item parent-rated questionnaire that evaluates the child’s autistic traits in terms of social communication, awareness, motivation, cognition, and behavior flexibility within the past six months. Items are rated on a 4-point Likert scale (ranging from 0 to 3), with higher scores indicating more autistic traits (Constantino & Gruber, 2012).
ADHD Rating Scale-IV
The ADHD-RS is an 18-item questionnaire that reports the frequency of symptoms over the past six months on a 4-point Likert scale, measuring symptoms of ADHD according to the DSM-IV. The total scale scores range from 0 to 54 (Tani et al., 2010).
The sample size was calculated based on two-sample t-tests using the G*Power 188.8.131.52 software (Faul et al., 2009). An effect size of 0.5, a significance level of α = 0.05, a statistical power of 1-β = 0.8, and a 1:2 allocation ratio between the ASD and without ASD groups were also considered. Sample size calculation was performed before initiating recruitment, and we set a total sample size of 114 participants.
The study results are expressed as the mean ± standard deviation (SD) for continuous variables and as numbers and percentages for categorical variables. Descriptive statistics were used to describe the distribution of participants’ characteristics. Chi-square tests were used for categorical variables. We performed multiple linear regression analysis to explore the correlation between the IAT score and factors such as the QIDS score, ADHD-RS score, and SRS-2 score. All tests were two-sided, and the significance level was set at 5%. All data were analyzed using SPSS Statistics software (version 23.0; IBM Corp., Armonk, NY, USA) for Windows and R version 4.1.0.
The surveys were conducted using a self-report questionnaire and a parent-report questionnaire. The questionnaires were handed to the participants and their parents by a doctor during their first visit. Before the research, the doctor explained to participants and their parents that: 1) participation was voluntary, and 2) strict confidentiality would be maintained. Written informed consent and assent forms were obtained from the participants and their parents. The study was approved by the Institutional Review Board of the Ehime University Graduate School of Medicine (IRB No. 1507007). All participants signed an informed consent form in accordance with the Declaration of Helsinki.