A comparison between three psychogeriatric rating scales

This study compares a new psychogeriatric rating scale, the Organic Brain Syndrome (OBS) scale, which is a combined observation and interview scale, with two other scales. Twenty‐eight elderly demented patients took part in the study. The OBS scale was compared to the Gottfries, Bråne and Steen (GBS) scale, the Mini Mental State Examination (MMSE) scale and a global rating. The correlations between OBS, GBS and MMSE were high, showing that the concurrent validity is good. The ratings of the OBS scale were independent of the patient's physical disabilities as measured by Katz's index, ie the discriminant validity was good. The analyses show similarities and differences between the clinical dimensions described in the rating scales. The OBS scale contributes unique clinical information and is a valid instrument for assessment of dementia symptoms.