Psychological understanding of psychotic-like experiences (PLEs) occurring in childhood is limited, with no recognised conceptual framework to guide appropriate intervention. We examined the contribution to PLE severity of emotional, cognitive and socio-environmental mechanisms thought to influence the development and maintenance of psychosis. Forty 8-14 year olds referred to a community Child and Adolescent Mental Health Service completed a battery of questionnaires and assessments measuring severity of PLEs, emotional problems, cognitive biases, and negative life events. 85% of children assessed reported having experienced a PLE over the previous year; and 55% reported more than one. 60% had experienced at least one in the previous fortnight. Multiple linear regression demonstrated that each of the variables made a significant and independent contribution to PLE severity, after adjusting for verbal ability and age, accounting together for more than half of the variance (reasoning B = 6.324, p = .049; emotion B = 1.807, p = .005; life events B = 4.039, p = .001). PLEs were common in this clinical sample of children. Psychological factors implicated in the development and maintenance of psychosis in adults were also associated with PLE severity in these children. PLE severity may be reduced by targeting each of these factors in cognitive therapy, at this very early stage. Any improvements in emotional wellbeing and functioning may then increase future resilience.

Background: In cognitive models of adult psychosis, schematic beliefs about the self and

Cognitive therapy is recommended for children with psychotic-like, or unusual, experiences associated with distress or impairment (UEDs; UK National Institute for Health and Care Excellence, 2013 [1]). Accurate models of the psychological underpinnings of childhood UEDs are required to effectively target therapies. Cognitive biases, such as the jumping to conclusions data-gathering bias (JTC), are implicated in the development and maintenance of psychosis in adults. In this study, we aimed to establish the suitability for children of a task developed to assess JTC in adults. Eighty-six participants (aged 5-14 years) were recruited from Child and Adolescent Mental Health Service (CAMHS) and community (school) settings, and completed the probabilistic reasoning ('Beads') task, alongside measures of intellectual functioning, general psychopathology, and UEDs. Self-reported reasoning strategy was coded as 'probabilistic' or 'other'. Younger children (5-10 years) were more likely than older children (11-14 years) to JTC (OR = 2.7, 95 % CI = 1.1-6.5, p = 0.03); and to use non-probabilistic reasoning strategies (OR = 9.4, 95 % CI = 1.7-48.8, p = 0.008). Both UED presence (OR = 5.1, 95 % CI = 1.2-21.9, p = 0.03) and lower IQ (OR = 0.9, 95 % CI = 0.9-1.0, p = 0.02) were significantly and independently associated with JTC, irrespective of age and task comprehension. Findings replicate research in adults, indicating that the 'Beads' task can be reliably employed in children to assess cognitive biases. Psychological treatments for children with distressing unusual experiences might usefully incorporate reasoning interventions.

Children's NSBs may mediate the adverse psychological impact of victimisation, and are appropriate treatment targets for young people with UEDs. Early educational intervention to reduce negative appraisals of the self and others may increase resilience to future adverse experiences and reduce later mental health risk.

The psychosocial processes implicated in the development and maintenance of psychosis differ according to both the dimensional attributes (conviction, frequency, associated distress, adverse life impact) and the content or type (e.g., grandiosity, hallucinations, paranoia) of the psychotic symptoms experienced. This has informed the development of 'targeted' cognitive behavioural therapy for psychosis (CBTp): interventions focusing on specific psychological processes in the context of particular symptom presentations. In adults, larger effect sizes for change in primary outcomes are typically reported in trials of targeted interventions, compared to those for trials of generic CBTp approaches with multiple therapeutic foci. We set out to test the theoretical basis for developing targeted CBTp interventions for young people with distressing psychotic-like, or unusual, experiences (UEs). We investigated variations in the psychosocial processes previously associated with self-reported UE severity (reasoning, negative life events, emotional problems) according to UE dimensional attributes and content/type (using an established five-factor model) in a clinically referred sample of 72 young people aged 8-14 years. Regression analyses revealed associations of conviction and grandiosity with reasoning; of frequency, and hallucinations and paranoia, with negative life events; and of distress/adverse life impact, and paranoia and hallucinations, with emotional problems. We conclude that psychological targets for intervention differ according to particular characteristics of childhood UEs in much the same way as for psychotic symptoms in adults. The development of targeted interventions is therefore indicated, and tailoring therapy according to presentation should further improve clinical outcomes for these young people.Key words: psychotic-like experience (PLE); cognitive model; psychosis; cognitive therapy; CBT 4 IntroductionUnusual, or psychotic-like, experiences are changes in thinking and perception that are phenomenologically similar to the symptoms of psychosis, for example, hearing a voice that no-one else can hear [1]. The prevalence of such experiences in childhood is high (around two-thirds of the general population, by self-report) suggesting that they cannot be considered, in isolation, to reliably confer increased risk of psychosis [2]. Rather, it seems that increasing likelihood of future mental illness is determined by particular characteristics and correlates of unusual experiences (UEs), such as associated distress and adverse life events [3,4]. This is consistent with the continuum premise underpinning cognitive models of the development and maintenance of psychosis [5,6]. In these models, UEs are one of a multiplicity of biopsychosocial factors that are hypothesised to cumulatively increase the risk of developing psychosis, but are not in themselves, indicative of 'illness'. Although the degree of continuity of psychotic symptoms with normal experiences has been questioned [7], the implication that UEs ...