Validation of the Delirium Diagnostic Tool-Provisional (DDT-Pro) With Medical Inpatients and Comparison With the Confusion Assessment Method Algorithm

Abstract

Delirium remains underdetected as a result of its broad constellation of symptoms and the inadequate neuropsychiatric expertise of most medical-surgical clinicians. Brief, accurate tools are needed to enhance detection. Methods:The authors extended validation of the Delirium Diagnostic Tool-Provisional (DDT-Pro), originally validated in a study of inpatients with traumatic brain injury for diagnosis of delirium by nonexpert clinicians, for 200 general medical inpatients in Colombia. The three structured, quantitatively rated items in DDT-Pro represent the three core delirium domains.Results: High interrater reliability between physician and nurse (0.873) administrators, internal consistency (.0.81), and content validity were found. Compared with independent reference standard diagnosis with DSM-5 or the Delirium Rating Scale-Revised-98, the area under the receiver operating characteristic (ROC) curve (global diagnostic accuracy) range was 93.8%296.3%. ROC analysis revealed the same cutoff score (#6) as that for the original study, with somewhat lower sensitivities of 88.0%290.0% and specificities of 85.3%281.2% (independent expert physician or nurse ratings). Even when rated by a trained expert physician, the original version of the Confusion Assessment Method algorithm (CAM-A) performed moderately, with lower sensitivities (61.8%270.0%) than the DDT-Pro (88.0%2 100%) and somewhat higher specificities (84.8%295.3% versus 67.4%286.7%), with values depending on dementia status, reference standard, and rater type. Accuracies for the DDT-Pro and CAM-A were comparable (DDT-Pro: 83.0%2 87.5% versus CAM-A: 87.5%288.5%), although lower in the dementia subgroup, especially for CAM-A. However, these tools were significantly discordant, especially in negative cases, which suggests that they do not detect diagnosis of patients in the same way. Conclusions:The DDT-Pro had high validity and reliability in provisional delirium diagnosis by physicians and nonexpert clinicians, although further validation is warranted before widespread use can be recommended.

Etiologies of Delirium in Consecutive COVID-19 Inpatients and the Relationship Between Severity of Delirium and COVID-19 in a Prospective Study With Follow-Up

“…Delirium diagnosis was made according to DSM-5 criteria (21); delirium severity was assessed with the DDT-Pro (22,23) and etiologies tabulated with the DEC (24). COVID-19 severity was measured with the CCSS (25,26).…”

“…DDT-Pro. The DDT-Pro is a three-item brief structured scale for provisional diagnosis and severity of delirium, which can be administered by any health care professional; it has been validated in traumatic brain injury and medical-surgical samples (22,23). It contains structured and quantitatively scored items for evaluating vigilance (item 1) and comprehension (item 2) adapted from the Cognitive Test for Delirium (CTD) (28) that are assessed directly through patient performance without needing verbal responses (useful in mechanically ventilated patients), and sleep-wake cycle disturbance (item 3), a descriptively anchored item from the Delirium Rating Scale-Revised-98 (DRS-R-98) (29), rated using all sources of clinical information for the preceding 12-24 hours.…”

“…Item 3 rating values were reversed to align with the scoring for the CTD items. These items represent symptoms from each of the three core domains that are characteristic of delirium (cognitive, higher-level thinking, and circadian) (22,23,30). Total DDT-Pro scores range from 9 points (best) to 0 (worst), where each item is scored 0-3.…”

“…Total DDT-Pro scores range from 9 points (best) to 0 (worst), where each item is scored 0-3. The best cutoff for diagnosing delirium is a DDT-Pro score #6, with scores ranging from 7 to 9 indicating nondelirium (22,23). It has two alternate equivalent forms, A and B, for items 1 and 2.…”

Distinguishing characteristics of delirium in a skilled nursing facility in Spain: Influence of baseline cognitive status

“…Using a cutoff of >6 points for nondelirium, the DDT-Pro had 100% sensitivity and 94.4% specificity for DSM-IV delirium in subacute traumatic brain injury patients 33. Subsequent validation in general hospital patients reconfirmed the cutoff score, with high sensitivity and moderately high specificity, including in subset of patients with preexisting cognitive impairment 34. Given our current findings in SNF patients that these same three symptoms, as measured using the DRS-R98, distinguished patients with delirium from those without it irrespective of their MCI-DEM status, validation of the DDT-Pro in SNF settings is warranted.…”