Evaluating ADHD medication trial representativeness: a Swedish population-based study comparing hypothetically trial-eligible and trial-ineligible individuals.

Background: Randomised controlled trials (RCTs) evaluating ADHD medications often use strict eligibility criteria, potentially limiting generalisability to patients in real-world clinical settings. We aimed to identify the proportion of individuals with ADHD who would be ineligible for medication RCTs and evaluate differences in treatment patterns and clinical and functional outcomes between RCT-eligible and RCT-ineligible individuals.

Methods: We used multiple Swedish national registries to identify individuals with ADHD, aged at least 4 years at the age of diagnosis, initiating pharmacological treatment between Jan 1, 2007, and Dec 31, 2019, with follow-up up to Dec 31, 2020.

Sex differences in clinically diagnosed psychiatric disorders over the lifespan: a nationwide register-based study in Sweden.

Background: Limited studies exist on sex differences in incidence rates of psychiatric disorders across the lifespan. This study aims to analyze sex differences in the incidence rates of clinically diagnosed psychiatric disorders over the lifespan.

Methods: We conducted a nationwide register-based cohort study, including all individuals who were born in Sweden and lived in Sweden between 2003 and 2019, including 4,818,071 females and 4,837,829 males.

All-Cause and Cause-Specific Mortality in Tourette Syndrome and Chronic Tic Disorder.

Background: Tourette syndrome (TS) and chronic tic disorder (CTD) may be associated with an increased risk of mortality, but specific causes of death are poorly understood.

Objectives: In this matched cohort and sibling cohort study, we estimated the risk of all-cause and cause-specific mortality in individuals with TS/CTD, compared with unaffected matched individuals and unaffected full siblings.

Methods: We identified all individuals diagnosed with TS/CTD in the Swedish National Patient Register who were living in the country between 1973 and 2020 and matched them (1:10) to individuals without TS/CTD from the general population.

Association between bullying victimization and obsessive-compulsive disorder: a population-based, genetically informative study.

The extent to which bullying victimization is associated with an increased risk of obsessive-compulsive disorder (OCD) has received little empirical attention. This longitudinal, population-based, genetically informative study examined whether self-reported bullying victimization at age 15 was associated with a clinical diagnosis of OCD in the Swedish National Patient Register and with self-reported obsessive-compulsive symptoms (OCS) at ages 18 and 24 in 16,030 twins from the Child and Adolescent Twin Study in Sweden. Using a discordant twin design, including monozygotic (MZ) and dizygotic (DZ) twins, each twin was compared with their co-twin, allowing a strict control of genetic and environmental confounding.