Increased likelihood of distressing and functionally impairing psychotic-like experiences among children with co-occurring internalising and externalising problems.

Among children with psychotic-like experiences (PLEs), the presence of co-occurring psychopathology may distinguish children's self-report of clinically significant experiences (i.e., PLEs that are distressing and/or impairing of daily functioning) from reports of more benign experiences. The aim of this study was to examine whether the likelihood of distressing or impairing PLEs differed according to type of co-occurring psychopathology symptoms. A community sample of 5268 children aged 9-12 years were recruited from Greater London, UK. Participants completed the Psychotic-Like Experiences Questionnaire for Children, and the Strengths and Difficulties Questionnaire to measure internalising and externalising problems. Multinomial logistic regressions were used to determine the likelihood of PLEs being distressing and/or impairing (vs. not) among children with different co-occurring symptom profiles (PLEs only; PLEs with internalising problems only - PLE-I; PLEs with externalising problems only - PLE-E; and PLEs with both internalising and externalising problems - PLE-IE). Children with co-occurring internalising and/or externalising problems had greater odds of distressing and/or impairing PLEs compared to children without co-occurring psychopathology (PLEs only). These associations were moderate for PLE-E and strong for PLE-I and PLE-IE, with the greatest odds of distressing and impairing PLEs evident in the presence of internalising plus externalising comorbidities (odds ratios [with 99 % confidence intervals] for PLE-IE relative to PLE-I = 2.00 [1.34-2.99]; PLE-IE relative to PLE-E = 5.46 [3.78-7.90]). These results affirm the importance of screening for the presence and type of co-occurring psychopathology among children with PLEs to demarcate potentially different treatment needs.