Poor adherence is a major obstacle in the management of patients suffering from schizophrenia. Previous studies on adherence have addressed the role of patients' subjective feelings and attitudes towards treatment. Rebelliousness is a more general cognitive-behavioral trait. No attempt has been made to investigate the correlation between rebelliousness and adherence to treatment.

To evaluate rebelliousness levels and their possible correlation with adherence among patients suffering from schizophrenia-spectrum disorders.

1) Compared rebelliousness levels among healthy subjects, patients suffering from schizophrenia spectrum disorders, and non-psychotic patients.

2) Examine the correlation between levels of rebelliousness and nonadherence among patients.

Rebelliousness was evaluated among 75 patients suffering from schizophrenia or schizoaffective disorder, 53 patients suffering from non-psychotic disorders, and 64 healthy subjects using the Rebelliousness Scale. Patients' adherence was evaluated using the Drug Attitude Inventory (DAI-10).

A significant negative correlation was found in the schizophrenia group between levels of rebelliousness and adherence (r = −.434, p < .001). In a regression model rebelliousness levels were found to be the strongest predictor of adherence (β = −0.236, p < .05) compared with other demographic variables. No significant difference was found in the levels of rebelliousness among the schizophrenia, non-psychotic disorders, or control groups.

Rebelliousness seems to be an independent predictor of adherence, specifically among patients suffering from schizophrenia. If future prospective studies replicate our results the Rebelliousness Scale might serve as an efficient tool to predict adherence.