Predicting schizophrenic relapse: a comparison of two measures.

A parental environment placing schizophrenic patients at high risk to relapse has been defined by two measures. One assessing expressed emotion (EE) is 'objective', but takes a considerable time to administer and requires a highly trained rater. The other involves use of a self-report measure (the Parental Bonding Instrument or PBI) which is acceptable in clinical groups and requires only a brief period for completion. The degree to which the two measures predict the course of schizophrenia in patients discharged to their families is examined in representative studies. Each measure is assessed in terms of its sensitivity, specificity, odds ratio and overall diagnostic power, after calibrating modified PBI cut-off scores against rehospitalisation data. The PBI is a potentially useful clinical aid to predicting relapse in schizophrenic patients who return to the home environment.