An empirical study of different diagnostic criteria for delirium among elderly medical inpatients.

This study compared the sensitivity and specificity of DSM-IV criteria for delirium with the sensitivity and specificity of DSM-III and ICD-10 criteria among elderly medical inpatients with or without dementia. Secondary objectives were to examine the effect of changing the definition of criterion A on sensitivity and specificity and to compare the sensitivity and specificity of different numbers of symptoms of delirium. A total of 322 elderly patients who had been admitted from the emergency department to the medical services were classified into one of four groups using DSM-III-R criteria: delirium and dementia (n = 128), delirium only (n = 40), dementia only (n = 94), and neither (n = 60). The sensitivity and specificity of DSM-IV, DSM-III, and ICD-10 criteria were determined against DSM-III-R criteria using three definitions of criterion A (clouding of consciousness only, clouding of consciousness and inattention, clouding of consciousness or inattention). When criterion A was defined as clouding of consciousness or inattention, the sensitivity and specificity of DSM-IV, DSM-III, and ICD-10 criteria were 100% and 71%, 96% and 91%, and 61% and 91%, respectively. The results were similar among patients with or without dementia. The lower specificity of DSM-IV was accounted for by its inclusion of patients who did not show disorganized thinking. DSM-IV criteria for delirium are the most inclusive criteria to date for elderly medical patients with or without dementia.