The expressed emotion (EE) index may not be as stable as it was once believed to be. The aim of this study was to identify variables associated with spontaneous change from low to high and from high to low levels of EE and EE subscales--critical comments (CC), hostility (H), emotional overinvolvement (EOI). Using a longitudinal, prospective study design, of 59 relatives having at least weekly face-to-face contact with 40 patients with an acute episode or relapse into schizophrenia (DSM-III-R) were interviewed by means of the Camberwell Family Interview (CFI) at admission and at 4 1/2 months after discharge. The results showed that high-high or unstable levels of CC, H or EE were associated with the patient not working or studying prior to admission. Relatives with low-high and high-high EOI patterns had more weekly face-to-face contact with the patient prior to admission than relatives with a low-low EOI pattern. Patients whose relatives had low-high CC and EE patterns were less ill at admission than patients whose relatives had low-low patterns. Higher perceived family burden was associated with, at admission, an unstable pattern of CC, and at follow-up, high-high EOI or EE patterns rather than low-low patterns. Our study suggests that it is possible to identify which relatives will have a stable and which a changing EE level, allowing for more focused intervention.