The aim of this research project was to develop an instrument to measure acknowledgment and denial of illness in hospitalized psychiatric patients.The investigators developed a 23-item, 4-point self report scale, the Patient's Experience of Hospitalization (PEH), and collected validity data from a sample of inpatients. A total of 29 subjects completed the PEH, the Marlowe-Crowne Social Desirability Inventory (MCSD), the MMPI, and a Global Assessment Scale (GAS) report. The patients' psychotherapists also provided GAS scores.Kuder Richardson split-half reliability and point biserial correlations of 18 items were adequate. The PEH total score correlated significantly and positively with the difference between the GAS scores assigned to the patient by the patient and by the therapist, with the patient's self-report GAS score, with MCSD scores and with the MMPI L and K scales, considered to assess crude and subtle defensive denial. Correlations with MMPI clinical scales (symptom reports) were negative, further supporting the idea of the PEH as a measure of denial.