Factor structure of the Mini-Mental State Examination in adult psychiatric inpatients.

The factor structure of the Mini-Mental State Examination (MMSE) has been examined primarily in geriatric populations using differing methodology and yielding inconsistent results. This study examined the MMSE in 339 adult inpatients at a nonforensic state psychiatric hospital. Data were analyzed in the form of 30 dichotomous variables (1 for each scored response). A 5-factor oblique solution was retained, comprising factors of Orientation, Attention-Working Memory, Verbal Recall, Comprehension-Praxis, and Naming. Higher order factors of Executive Functioning and Language-Praxis were also found. The results fit the traditional neurocognitive domains of a mental status examination and generally replicated findings from the 2 largest studies published to date despite differences in population, suggesting that the obtained factors are fairly robust.