Aim The objective of this study was to identify possible pre‐ and postnatal factors influencing neurodevelopment of the young child. Methods We used data from the Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010) mother–child cohort, but excluded those with a neurological diagnosis, born <37 weeks of gestation and birthweights <2500 g, resulting in 650 children analysed. Neurodevelopment was assessed as age of achievement of early milestones, language scores at 1 and 2 years and cognitive score at 2 ½ years of age. Results Neurodevelopmental scores were not associated with breastfeeding, persistent wheeze, eczema and number of sick days (p > 0.05 in all tests). Early age at milestone achievement was associated with male sex (p = 0.05), lower maternal age (p = 0.02), higher gestational age (p < 0.001) and paternity leave (p = 0.01). A higher 1‐year language score was associated with female sex (p = 0.02) and maternal smoking during pregnancy (p = 0.01) and a higher 2‐year language score with female sex (p < 0.001) and being first born (p = 0.01). A higher cognitive score was associated with female sex (p = 0.02). Conclusion Neurodevelopmental scores were unrelated to breastfeeding, persistent wheeze, eczema and number of sick days. Neurodevelopment in early childhood was mostly associated with gender.

Background Cognitive behavioural therapy (CBT) is the recommended first-line treatment for children and adolescents with obsessive-compulsive disorder (OCD), but evidence concerning treatment-specific benefits and harms compared with other interventions is limited. Furthermore, high risk-of-bias in most trials prevent firm conclusions regarding the efficacy of CBT. We investigate the benefits and harms of family-based CBT (FCBT) versus family-based psychoeducation and relaxation training (FPRT) in youth with OCD in a trial designed to reduce risk-of-bias. Methods This is an investigator-initiated, independently funded, single-centre, parallel group superiority randomised clinical trial (RCT). Outcome assessors, data managers, statisticians, and conclusion drawers are blinded. From child and adolescent mental health services we include patients aged 8–17 years with a primary OCD diagnosis and an entry score of ≥16 on the Children’s Yale-Brown Obsessive-Compulsive Scale (CY-BOCS). We exclude patients with comorbid illness contraindicating trial participation; intelligence quotient < 70; or treatment with CBT, PRT, antidepressant or antipsychotic medication within the last 6 months prior to trial entry. Participants are randomised 1:1 to the experimental intervention (FCBT) versus the control intervention (FPRT) each consisting of 14 75-min sessions. All therapists deliver both interventions. Follow-up assessments occur in week 4, 8 and 16 (end-of-treatment). The primary outcome is OCD symptom severity assessed with CY-BOCS at end-of-trial. Secondary outcomes are quality-of-life and adverse events. Based on sample size estimation, a minimum of 128 participants (64 in each intervention group) are included. Discussion In our trial design we aim to reduce risk-of-bias, enhance generalisability, and broaden the outcome measures by: 1) conducting an investigator-initiated, independently funded RCT; 2) blinding investigators; 3) investigating a representative sample of OCD patients; 3) using an active control intervention (FPRT) to tease apart general and specific therapy effects; 4) using equal dosing of interventions and therapist supervision in both intervention groups; 5) having therapists perform both interventions decided by randomisation; 6) rating fidelity of both interventions; 7) assessing a broad range of benefits and harms with repeated measures. The primary study limitations are the risk of missing data and the inability to blind participants and therapists to the intervention. Trial registration ClinicalTrials.gov: NCT03595098, registered July 23, 2018.