Lee Hae-kook
Clinicians & Public Health · Catholic University of Korea
Korean psychiatrist whose iCURE cohort research helped inform WHO's recognition of gaming disorder.
Lee Hae-kook is a psychiatrist at the Catholic University of Korea who leads the iCURE adolescent cohort studies, tracking how young people's internet and gaming habits relate to their mental health over time. His research was among the evidence cited when the World Health Organization formally recognized "gaming disorder" in its ICD-11 diagnostic manual. That recognition made South Korea — where concern about gaming and internet use among young people has long been a matter of public debate — an internationally significant site for both the science and the clinical treatment of compulsive gaming.
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WORKS IN THE LIBRARY (11)
STUDIES
Study Protocol of the Internet User Cohort for Unbiased Recognition of Gaming Disorder in Early Adolescence (iCURE), Korea, 2015–2019
This BMJ Open paper lays out the design of iCURE, a multi-year prospective study that enrolled roughly 3,000 Korean adolescents across 21 schools starting in 2015. Psychiatrist Hae Kook Lee of the Catholic University of Korea is among the co-authors of this founding protocol, which describes tracking participants' internet and gaming habits alongside emotional, social, school, and family measures over several years. Rather than a single snapshot, the cohort design lets researchers observe which factors are associated with the emergence, remission, and recurrence of patterns linked to internet gaming disorder in the same young people over time. TechKids Foundation includes this protocol paper as the methodological foundation behind Lee's later iCURE findings on gaming-disorder risk, physical health, sleep, and mood in adolescents, several of which are cited elsewhere in this library.
Gaming Patterns and Related Symptoms in Adolescents Using Cluster Analysis: Baseline Results From the Internet User Cohort for Unbiased Recognition of Gaming Disorder in Early Adolescence (iCURE) Study
Drawing on baseline data from the iCURE cohort, this Environmental Research paper by Hyunsuk Jeong, Hae Kook Lee, and colleagues sorted more than 2,300 Korean adolescents into three clusters based on their gaming patterns and related risk and protective factors. One cluster — about a fifth of participants — combined heavier gaming with co-occurring psychological and social difficulties and showed markedly higher odds of screening into internet-gaming-disorder-associated risk than a cluster with few such difficulties. A third, intermediate cluster fell between the two. The authors frame the analysis as evidence that gaming-related risk tends to cluster together with other warning signs rather than occurring in isolation, supporting targeted screening over one-size-fits-all approaches. TechKids Foundation cites this as part of the broader iCURE evidence behind co-occurring risk patterns in adolescents.
Reciprocal Relationship Between Depression and Internet Gaming Disorder in Children: A 12-Month Follow-up of the iCURE Study Using Cross-Lagged Path Analysis
Published in the Journal of Behavioral Addictions, this iCURE-cohort paper by Hyunsuk Jeong, Hae Kook Lee, and colleagues followed 366 Korean elementary-school internet users for a year to test which comes first: depressive symptoms or gaming-disorder-associated behavior. Using cross-lagged statistical modeling, the authors report a two-way association — children with more depressive symptoms at the start tended to show more severe gaming-disorder-associated features a year later, and children with more severe gaming-disorder-associated features at the start tended to show more depressive symptoms a year later. Neither path was dramatically larger than the other. The authors suggest the two are linked in a reinforcing loop rather than one simply causing the other, and argue that programs addressing children's gaming habits should also screen for mood symptoms, and vice versa. TechKids Foundation cites this as evidence that gaming-related risk and depression in children are best understood together.
Prospective Association Between Online Game Use and Risk of Internet Gaming Disorder in Korea: 12-Month Follow-up Results From the iCURE Study
This Asia-Pacific Journal of Public Health paper, co-authored by Hae Kook Lee, followed 1,318 Korean adolescent gamers from the iCURE cohort for a year to see how changes in their gaming behavior related to risk of internet gaming disorder. The authors defined heavier use as gaming more than 1.5 hours a day or on 4 or more days a week, and report that adolescents whose gaming time increased over the study period were about 2.5 times as likely to move into gaming-disorder-associated risk as those who stayed below that threshold, while adolescents whose gaming frequency increased were nearly 4 times as likely. The authors frame these thresholds as a practical reference point for parents and clinicians rather than a hard clinical cutoff. TechKids Foundation cites this as association-level evidence linking specific increases in gaming time and frequency to elevated gaming-disorder risk in Korean adolescents.
Risk Factors and Outcomes of Internet Gaming Disorder Identified in Korean Prospective Adolescent Cohort Study
Published in the Journal of Behavioral Addictions, this iCURE-cohort study — with Hae Kook Lee among the co-authors — followed Korean adolescents for a year to see how internet-gaming-disorder-associated risk related to physical-health and daily-life outcomes, not just psychological ones. The authors report that adolescents who screened at risk for gaming disorder at the study's start had lower physical activity and less sleep than lower-risk peers, and reported more dry-eye symptoms, more musculoskeletal pain, and more near-miss accidents — with these gaps widening over the following year rather than narrowing. The authors describe gaming-disorder-associated risk as linked to a broader pattern of physical strain in adolescents, not only mood or behavior. TechKids Foundation cites this as evidence that gaming-related risk in children carries physical, not only psychological, warning signs.
Public Health Approach to Problems Related to Excessive and Addictive Use of the Internet and Digital Media
In this Current Addiction Reports paper, social-work researcher Sulki Chung and psychiatrist Hae Kook Lee lay out a public-health framework for excessive and addictive internet and digital-media use, distinct from an individual-treatment-only lens. They describe risk as arising from the interaction of three elements — the person, the digital product itself, and the surrounding environment — and argue that responses should combine individual-level support with product-design and policy-level measures, such as monitoring systems, service standards, and access or content rules for higher-risk platforms. Rather than framing problematic use as solely a personal issue to be managed case by case, the authors present it as a population-level public-health issue requiring coordinated, evidence-based services matched to severity. TechKids Foundation cites this as Lee's own policy framing of why gaming- and internet-related harms call for systemic, not only individual, responses.
Impact of COVID-19 on Adolescents' Smartphone Addiction in South Korea
This Social Work in Public Health study, co-authored by Hae Kook Lee, surveyed 360 Korean teenagers aged 15 to 18 about their smartphone use before and during the COVID-19 pandemic. The authors report that individual-level factors — including depressive symptoms, weaker self-control, and having been a target of cyberbullying — were associated with higher smartphone-addiction-associated scores, alongside family-level factors like household economic strain and lower parental involvement, and school-level factors like grades. Among teens whose screen time rose during the pandemic specifically, economic circumstances, academic performance, and grade level were also associated with higher risk. The authors frame pandemic-era school closures and isolation as a context that amplified pre-existing risk factors rather than creating an entirely new problem. TechKids Foundation cites this as evidence that pandemic disruption is associated with, not the sole cause of, elevated smartphone-related risk in Korean adolescents.
Recurrence of Internet Gaming Disorder in Korean Adolescents: A 24-Month Follow-up Study
Published in European Child & Adolescent Psychiatry, this iCURE-linked study by Sun-Jin Jo, Hae Kook Lee, and colleagues followed 1,452 Korean middle-school gamers for two years to see how often internet gaming disorder, once it eased, came back. The authors report a cumulative relapse rate of about 16 percent over the follow-up period — well above the roughly 4 percent rate at which the disorder had first emerged in the same sample — and identify starting to game before entering primary school as a factor associated with a substantially higher chance of relapse. The authors frame early gaming onset as a marker worth attention in relapse-prevention efforts, alongside continued monitoring after a young person's gaming-disorder-associated symptoms first improve. TechKids Foundation cites this as evidence that gaming-disorder-associated patterns in adolescents can recur, not simply resolve once and stay resolved.
Unintended Positive Behavioral Changes During Self-report and Wearable Data Collection on Digital Media Use in Young Adults
This Journal of Behavioral Addictions paper, co-authored by Hae Kook Lee, tracked 206 young adults over four weeks who were simply asked to self-report their digital-media use and wear a Fitbit, with no other intervention applied. The authors report that participants' digital-media use and high-risk-use scores dropped, and depressive symptoms eased, over the study period even though nothing was designed to change their behavior. They interpret this as a measurement effect: the act of tracking and reporting one's own screen habits appears itself to nudge people toward lighter use, at least temporarily. The authors caution that future studies testing digital-media interventions need control groups that also self-monitor, since a real intervention's effect could otherwise look larger than it actually is, simply because measurement alone moves the numbers. TechKids Foundation cites this as a methodological caution relevant to how gaming- and screen-use interventions are evaluated.
Health Response to Problematic Usage of the Internet: A Global Survey on Trends, Available Treatments and Key Challenges
Published in the Journal of Behavioral Addictions, this large international survey — coordinated through the International Society of Addiction Medicine's Global Expert Network and co-authored by Hae Kook Lee among more than 30 collaborators — asked addiction-medicine and psychiatry societies across 38 countries how their health systems respond to problematic internet use, including its gambling and gaming subtypes. Respondents most often named online gambling and gaming as the internet-use patterns causing concern, and reported that psychotherapy, especially cognitive behavioral therapy, was the most widely available response. The survey also found major gaps: most respondents said their country lacks professional certification standards for addressing problematic internet use, and a large majority rated the issue as important over the coming decade. TechKids Foundation cites this as evidence that health systems worldwide, including South Korea's, remain underprepared for gaming- and internet-related harms in young people.
Sex Differences in the Longitudinal Association Between High Risk of Internet Gaming Disorder and Subsequent Suicidality Among Adolescents: A Cohort Study
Published in the Journal of Behavioral Addictions, this iCURE-cohort study — co-authored by Hae Kook Lee — followed 1,874 Korean adolescents aged 9–14, none reporting suicidal thoughts at baseline, for two years to test whether gaming-disorder-associated risk was linked to later suicidality, and whether that association differed by sex. Among boys, those who screened at high risk for internet gaming disorder showed substantially higher rates of later suicidality — including suicidal ideation and suicide plans or attempts — than lower-risk boys, roughly 17 percent versus 5 percent. Among girls, the same comparison did not reach statistical significance. The authors frame high gaming-disorder-associated risk as one warning sign linked to elevated suicidality risk in boys specifically, not a standalone cause. TechKids Foundation includes this as association-level evidence that clinicians and parents should treat gaming-disorder risk in boys as a warning sign worth watching alongside other risk factors.