[Recall of the prime minister for the assessment of mental status].

A number of cognitive screening tests assess knowledge of the head of state or current prime minister. It is supposed that correct recall is a valid indicator of cognitive functioning. A consecutive sample of 259 visitors of a psychogeriatric day care center were rated for knowledge of the prime minister's name. Recall of his name was not dependent on level of education. The mean score on an independent screening test was significantly higher for those who knew the prime minister's name than for those who failed to answer the question. More men than women correctly answered the question, regardless of education level, living arrangements (living with someone versus being single and living alone), age and cognitive score. Using item response theory and Mokken scale analysis it was found that a short screening test containing the prime minister item constituted a scale of medium scalability (Loevinger's scalability coefficient H:0.50). Scores on the screening test correlated significantly with two independent measures of episodic and semantic memory. Deletion or addition of the prime minister item did not influence the degree of association between screening test and memory test scores. It is advisable to ask for the name of the prime minister in screening for cognitive impairment. Passing or failing the prime minister item correlates with intact or impaired retrieval of current information.