Prediction models in first episode psychosis: a systematic review and critical appraisal

Background: People presenting with first episode psychosis (FEP) have heterogenous outcomes. More than 40% fail to achieve symptomatic remission. Accurate prediction of individual outcome in FEP could facilitate early intervention to change the clinical trajectory and improve prognosis.

Aims: We aim to systematically review evidence for prediction models developed for predicting poor outcome in FEP.

Methods: A protocol for this study was published on the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42019156897. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance, we systematically searched six databases from inception to 28th January 2021. We used the CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies (CHARMS) and the Prediction model Risk Of Bias Assessment Tool (PROBAST) to extract and appraise the outcome prediction models. We considered study characteristics, methodology and model performance.

Results: Thirteen studies reporting 31 prediction models across a range of clinical outcomes met criteria for inclusion. Eleven studies employed logistic regression with clinical and sociodemographic predictor variables. Just two studies were found to be at low risk of bias. Methodological limitations identified included a lack of appropriate validation, small sample sizes, poor handling of missing data and inadequate reporting of calibration and discrimination measures. To date, no model has been applied to clinical practice.

Conclusions: Future prediction studies in psychosis should prioritise methodological rigour and external validation in larger samples. The potential for prediction modelling in FEP is yet to be realised.