Trajectories of change in self-reported psychotic-like experiences in childhood and adolescence.

Background: Psychotic-like experiences (PLEs) during adolescence are not uncommon and potentially represent a clinical and public health concern. A greater understanding of their aetiology and patterns of change over time is needed. We aimed to describe trajectories of PLEs during adolescence, and examine their association with characteristics earlier during development.

Method: This was a cohort study of 7387 adolescents from the ALSPAC birth cohort who completed self-reported questionnaires about PLEs at 4 time points over a five-year period (ages 11.5-16.5years). Association between childhood characteristics and latent class membership was examined.

Results: The proportion of children reporting PLEs declined with age. Individuals within decreasing (1.7%), intermittent (16.8%), and persistent (0.9%) PLEs trajectories were more likely to come from adverse backgrounds and have disturbed childhood development compared to the low PLE (80.6%) class. Persistent-class individuals scored highest on most measures though no measure clearly distinguished between persistent, intermittent and decreasing groups.

Conclusions: A number of early life characteristics and markers of childhood emotional and behavioural development are associated with trajectories of PLEs during adolescence. Despite the increase in cost and time required to collect data at repeated intervals, studies of trajectories are likely to have greater potential for predicting transition into clinical disorder at an earlier stage.