BackgroundOver the past decade, smartphone use has become widespread amongst today’s children and young people (CYP) which parallels increases in poor mental health in this group. Simultaneously, media concern abounds about the existence of ‘smartphone addiction’ or problematic smartphone use. There has been much recent research concerning the prevalence of problematic smartphone use is in children and young people who use smartphones, and how this syndrome relates to mental health outcomes, but this has not been synthesized and critically evaluated.AimsTo conduct a systematic review and meta-analysis to examine the prevalence of PSU and quantify the association with mental health harms.MethodsA search strategy using Medical Subject Headings was developed and adapted for eight databases between January 1, 1st 2011 to October 15th 2017. No language restriction was applied. Of 924 studies identified, 41 were included in this review, three of which were cohort studies and 38 were cross sectional studies. The mental health outcomes were self-reported: depression; anxiety; stress; poor sleep quality; and decreased educational attainment, which were synthesized according to an a priori protocol.ResultsThe studies included 41,871 CYP, and 55% were female. The median prevalence of PSU amongst CYP was 23.3% (14.0–31.2%). PSU was associated with an increased odds of depression (OR = 3.17;95%CI 2.30–4.37;I2 = 78%); increased anxiety (OR = 3.05 95%CI 2.64–3.53;I2 = 0%); higher perceived stress (OR = 1.86;95%CI 1.24–2.77;I2 = 65%); and poorer sleep quality (OR = 2.60; 95%CI; 1.39–4.85, I2 = 78%).ConclusionsPSU was reported in approximately one in every four CYP and accompanied by an increased odds of poorer mental health. PSU is an evolving public health concern that requires greater study to determine the boundary between helpful and harmful technology use. Policy guidance is needed to outline harm reduction strategies.

After publication of our article [1] we were notified that one of the author names was misspelled.

An amendment to this paper has been published and can be accessed via the original article.

The degenerative nature of Huntington's disease drastically reduces quality of life for sufferers while limiting life expectancy itself. Among other sequalae, psychosis and chorea remain persistently difficult disease manifestations to manage for patients. Clozapine is an atypical antipsychotic medication with a multineuroreceptor affinity, which gives it a broad range of action. Clozapine has been documented to have good remedial actions on chorea and psychosis in patients with Huntington's disease. Here the authors make the case for further research.