The role of clinical autopsy in monitoring the quality of the clinical diagnosis in an emergency department

OBJECTIVE: A total of 61 autopsies performed in patients died in emergency department of a university hospital were retrospectively analysed and the findings were compared with clinical diagnoses. METHODS: Sensitivity and specificity of the clinical diagnoses and the correction of medical procedures were measured. The influence of age and sex of patients was analyzed using Fisher's exact test and chi-square-test. RESULTS: The most common causes of death were cardiovascular diseases (52.46%). Autopsy showed unexpected major findings in 44.26% of cases. Major discrepancies between the autopsy reports and the clinical diagnoses, were present in 26.22% of all cases. Absolute concordance between clinical and autopsy diagnoses was obtained in 44.26% of cases. The major sensitivity of clinical diagnosis was found in cerebrovascular disorders (100%), upper digestive hemorrhage (100%), and acute myocardial infarction (82.35%). The lowest sensitivity was found in malignant tumors (16.66%), hemorrhagic pancreatitis (0%) and bowel infarction (0%). The patient cares were correct in 68.85% of cases. No statistically significant differences were observed in relation to age and sex. CONCLUSIONS: We concluded that autopsy is a useful method for evaluate diagnostic procedures and quality of medical cares in emergency departments.     

Autopsy diagnoses of malignant neoplasms: how often are clinical diagnoses incorrect?

CONTEXT: Autopsy often reveals new diagnoses of malignant neoplasms, but as technological advances to improve diagnosis during life have improved, autopsy rates have declined dramatically. OBJECTIVE: To determine if there is still a high discordance rate between clinical and autopsy diagnoses of malignant neoplasms despite increasing technological advances in diagnostic methods. DESIGN AND SETTING: A 10-year retrospective study (1986-1995) of all autopsies performed at the Medical Center of Louisiana at New Orleans. PARTICIPANTS: All patients autopsied, excluding preterm fetuses, at the Medical Center of Louisiana at New Orleans, by both Tulane and Louisiana State University Schools of Medicine in which consent was obtained or authorization given from the Orleans Parish Coroner's Office. MAIN OUTCOME MEASURES: Discordance between clinical and autopsy diagnoses of malignant neoplasms. RESULTS: A total of 1625 cases were reviewed of which 520 preterm fetuses were excluded. Of the remaining 1105 cases, 654 were male and 451 were female. The mean age was 48.3 years (range, 1-98 years). A total of 433 neoplasms were diagnosed, 250 of which were malignant. One hundred eleven malignant neoplasms in 100 patients had been either undiagnosed or misdiagnosed, and in 57 patients, the immediate cause of death could be attributed to the malignant neoplasm. The discordance between clinical and autopsy diagnoses of malignant neoplasms in this study is 44%, which is similar to previously reported studies. CONCLUSION: The discordance rate between clinical and autopsy diagnoses of malignant neoplasms is large and confirms the importance of the postmortem examination.     

Accuracy of mortality data for interstitial lung diseases in New Mexico, USA

BACKGROUND: The sensitivity and accuracy of death certificates and mortality data as sources of population based data on the occurrence of interstitial lung diseases has received limited attention. To determine the usefulness of these data sources, death certificates and mortality data from patients in New Mexico were examined. METHODS: Patients with an interstitial lung disease were identified from a population based registry. For subjects who had died, diagnostic information from their death certificates and from mortality data was compared with the clinical diagnoses made before death. RESULTS: Of 385 patients with a clinical diagnosis of an interstitial lung disease, 134 died between October 1988 and August 1994. Death certificates were obtained for 96% of these patients. An interstitial lung disease was listed somewhere on the death certificate for only 46% of the patients, and as an immediate cause of death for only 15%. For the patients with an interstitial lung disease listed somewhere on the death certificate the overall concordance between the diagnoses before death and those on the death certificate was 76%. Mortality data for the State of New Mexico showed a diagnosis of interstitial lung disease to be the assigned cause of death for only 22% of the patients. The overall agreement between the diagnoses made before death and those of the state mortality data was only 21%. CONCLUSIONS: These results suggest that death certificates and state mortality data are neither sensitive nor accurate for describing the occurrence of interstitial lung diseases. This finding may partly explain the apparently low mortality rates from idiopathic pulmonary fibrosis in the USA compared with other countries.     

Adequacy of medical referrals to hospital emergency service

OBJECTIVE: To assess the correctness and diagnostic concordance in referrals of patients to hospital Casualty Departments (CD); and the possible differences between rural and urban health centres (HC) as well as between general practitioners (GP) and family and community medicine (FCM) specialists. DESIGN: Observational study of a crossover nature. SETTING: Health area 1 in the province of Badajoz. PATIENTS AND OTHER PARTICIPANTS: 800 patients, referred to their local hospital Casualty Department. MEASUREMENTS AND MAIN RESULTS: 50.5% of all referrals were considered justified. 15.1% of the patients referred were admitted to hospital. 50.7% of referrals from GPs were found to be correct, against 47% from FCM specialists; and 49% of those referred from rural HCs were correct, as against 45.9% of those referred from urban HCs (no significant differences). Only 54% of referrals had a diagnostic hypothesis, with diagnostic concordance at 50%. There was diagnostic concordance in 28.1% of GP referrals, against 33.3% of FCM specialists; and in 27.5% of those from rural HCs against 26.1% from urban HCs (no significant differences). CONCLUSIONS: We found no differences in the correctness of referrals or diagnostic concordance of patients seen in the CD of our city's health area, neither between patients referred from rural and urban HCs, nor between patients referred by GPs and FCM specialists.     

Reliability of the recording of hysterectomy in the Saskatchewan health care system

OBJECTIVE: To determine the validity of data pertaining to hysterectomy in the Saskatchewan health care utilisation datafiles. DESIGN: Retrospective analysis of routinely collected data covering hospital discharge records and practitioner claims for reimbursement of services, together with a review of clinical charts. SETTING: Province of Saskatchewan, Canada. SAMPLE: All 1905 cases of hysterectomy in one calendar year for analysis of datafiles and a random sample of 227 clinical charts for review. METHOD: Information in the hospitalisation datafile was validated through an external comparison with data extracted from a review of clinical charts, as well as an internal comparison with independent data from the practitioner claims file. Corresponding context data on drug use and performance of related procedures were also analysed. RESULTS: Concordance between hospital data and clinical charts was greater than 95% for those items of an administrative nature as well as type of hysterectomy and was around 85% for the diagnoses. When hospitalisation and practitioner claims data were compared, the concordance was 98% for type of hysterectomy but only 56% for diagnoses. CONCLUSIONS: The agreement between hospital data and clinical charts was excellent. The concordance between hospitalisation and practitioner claims data was almost exact for type of hysterectomy, while discrepancies in diagnoses between these files were mostly explainable on the basis of accepted clinical practice. Saskatchewan health care utilisation datafiles provide a source of valid data for research and evaluation studies.     

Autopsy in children with cancer who die while in terminal care

BACKGROUND: The purpose of this study was to find out whether autopsy of children with cancer should be recommended after terminal care, or whether in those circumstances it could be abandoned. PATIENTS AND METHODS: One hundred pediatric patients with cancer treated at the Children's Hospital, University of Helsinki, Finland, died during 1987-92. Seventy children died while in organized terminal care. The underlying diagnoses were brain tumors (21), other solid tumors (24), and leukemias (25). The method was a retrospective analysis of patients' records and autopsy reports, in addition to a structured interview of the two parents separately. RESULTS: Autopsy was performed in 40 (57%) of these 70 cases. It was more often performed on children dying in hospital (69%) than in those dying at home (39%). The autopsy rate also varied with the underlying disease: 68% of patients with leukemia, 50% of those with solid tumors, and 52% of those with brain tumors were autopsied. Autopsy afforded totally new medical information in 20% of cases, and important additional information in 55%. Nothing unexpected was found in 25%. Almost all the parents (94%) who agreed to autopsy felt that it was appropriate. Of both mothers and fathers, 50% felt that knowing the findings at autopsy was helpful for them, and all the parents except one mother thought that the autopsy of their child would at least be helpful to other patients. CONCLUSIONS: Autopsy often provides important and even unexpected information in those dying after terminal care. The majority of our parents felt that autopsy was an acceptable and appropriate practice. We recommend that autopsies should be performed, with the parents' consent, even after terminal care.     

Impact of sonography on the diagnosis and treatment of acute lower abdominal pain in children and young adults

OBJECTIVE: Our purpose was to evaluate the impact of sonographic data on clinical physicians' diagnostic confidence and their treatment of children and young adults with acute lower abdominal pain. SUBJECTS AND METHODS: Senior surgical and emergency department staff completed questionnaires before and after abdominal sonography was performed on 94 of 101 consecutive children and young adults with acute lower abdominal pain, pelvic pain, or both. Physicians who were unaware of sonographic data stated the most likely diagnosis and their level of confidence in their diagnosis and then formulated clinical plans. After they were given sonographic data, physicians again stated the most likely diagnosis, estimated their level of confidence, and formulated revised treatment plans. RESULTS: Sonographic data resulted in revised clinical diagnoses in 52% of the patients. Overall, the gain in diagnostic confidence for the entire study population was 33% (95% confidence interval [CI], 27-38%; p < .0001). The impact on the physicians' confidence was greater in those children and young adults whose diagnoses changed after sonography (mean increase in physicians' confidence, 48.3%; 95% CI, 47-75%). In patients whose diagnoses were not changed after sonography, the mean increase in physicians' confidence was 17.6% (95% CI, 11-24%; p < .0001 [analysis of variance]). Physicians used sonographic data to change initial treatment plans in 43 patients (46%). Of these 43 patients, a lower intensity of care was given to 30 patients (70%) and a higher intensity to 13 patients (30%). CONCLUSION: Sonographic data frequently changed initial clinical diagnoses, thus increasing diagnostic confidence and changing clinical treatment decisions in the setting of acute lower abdominal pain in children and young adults.     

The autopsy: still important in cardiac surgery

BACKGROUND: This study examined the ability of autopsy to confirm or dispute presumptive cause of death among cardiac surgery patients. METHODS: Autopsy reports were compared with mortality conference notes that were dictated prospectively before autopsy results were available. Between January 1985 and December 1995, there were 600 hospital deaths among 13,029 adult cardiac surgery patients (4.6% mortality). Of these 600 deaths, 147 (24.5%) had postmortem examination. RESULTS: Annual autopsy rate remained constant over the course of the study. Autopsied patients were younger (60.4 +/- 15 versus 66.7 +/- 13 years [mean +/- standard error of the mean]; p < 0.0001), but their race and sex distributions were similar to deceased patients not having autopsy. Autopsy confirmed clinical presumptive cause of death in 52% (76), disputed clinical diagnosis in 9.5% (14), provided definitive diagnosis in the absence of clinical diagnosis in 13.6% (20), and failed to provide definitive diagnosis in 25% (37). One third of autopsies (39%; 57) provided information that was clinically unrecognized and might have altered therapy and outcome if known premortem. As determined by autopsy, common causes of death were cardiac (27%; 39), unknown (25%; 37), sepsis (14%; 21), stroke (8.8%; 13), cholesterol embolism (4.1%; 6), pulmonary embolism (4.1%; 6), and adult respiratory distress syndrome (4.1%; 6). CONCLUSIONS: Autopsy reveals or confirms cause of death in nearly three quarters of cardiac surgical deaths and provides information that differs significantly from premortem clinical impression more than 20% of the time. As such, the autopsy remains important to quality assurance in cardiac surgical care.     

Misdiagnosis of lung cancer in a 2000 consecutive autopsy study in Budapest

OBJECTIVE: To determine the accuracy of lung cancer mortality data based on clinical observations in the absence of autopsy and to identify factors affecting the accuracy of diagnosis. METHODS: Admission, pre-autopsy and post-autopsy diagnoses were recorded for 1000 consecutive autopsies in each of two University departments in Budapest with high autopsy rates for persons dying in hospital. In those 87 cases where one or more diagnosis included primary lung cancer, additional data were collected concerning clinical investigations relevant to the diagnosis and the histological type lung cancer, and on smoking habits. RESULTS: 59% (36/61) of lung cancers seen at autopsy were not detected pre-autopsy, while 50% (25/50) of those diagnosed pre-autopsy were not confirmed at autopsy. Many misdiagnoses arose because patients were too ill to be properly investigated and/or died before investigations could be completed. Accuracy of diagnosis increased with the number of diagnostic techniques applied, but was still far from perfect in the absence of necropsy. Underdiagnosis was commoner in non-smokers and overdiagnosis commoner in smokers. CONCLUSIONS: Without necropsy, lung cancer misdiagnosis is common, especially when modern diagnostic procedures cannot be fully employed. Knowledge of smoking habits may affect diagnostic accuracy.     

Validity of the recording of ischaemic heart disease and chronic obstructive pulmonary disease in the Saskatchewan health care datafiles

The internal validity of the recording of information about ischaemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD) in the administrative health care datafiles of the Canadian province of Saskatchewan is investigated. Comparisons between hospital data and medical charts for acute myocardial infarction and chronic airways obstruction patients showed excellent diagnostic agreement: 97 per cent and 94 per cent, respectively. Appropriate physician service claims were identified for 89 per cent of hospitalizations for IHD and COPD and exact concordance between diagnoses in the two datafiles varied between 15 per cent for acute/sub-acute IHD and 80 per cent for asthma; including any physician diagnosis within the same broad category (IHD or COPD) increased concordance to 79-94 per cent for IHD and 64-88 per cent for COPD. Contextual information related to the hospitalizations was clinically and epidemiologically realistic.     

Biochemistry and biomechanics of healing tendon: Part I. Effects of rigid plaster casts and functional casts

OBJECTIVE: The state psychiatric hospital is experiencing an increase in medically sick and aging patients who die of natural causes while hospitalized. This study explored the "medicalization" of the state hospital by examining the prevalence of medical illness and its relationship with psychiatric illness and age among state hospital psychiatric inpatients who died of natural causes--deaths that were not accidents, homicides, or suicides. METHODS: A total of 179 inpatients who died of natural causes at Western State Hospital in Washington State between 1989 and 1994 were studied retrospectively through case file review. Their demographic and institutional characteristics and psychiatric diagnoses were compared with those of others treated at the hospital (N=9,258). The medical diagnoses of patients who died were analyzed by age and psychiatric condition. RESULTS: The patients who died were much older than the other patients treated during the study period. Two-thirds of those who died had organic mental disorders, mostly dementia, whereas only a fifth of the other patients had these disorders. The patients who died had a mean of eight physical illnesses, with a range from none to 21. Circulatory and respiratory conditions were most prevalent, affecting half to two-thirds of patients; these conditions had high rates of comorbidity with organic mental disorders. CONCLUSIONS: The characteristics of the state hospital population and the services provided are shifting in response to mental health reform and new policies on patient self-determination. Increased emphasis on medical care added to traditional psychiatric services will require increased financial and personnel resources.     

Functional state of the cardiovascular system of miners during prolonged adaptation to extreme circumstances

The hospital files of 410 patients with hematological malignancy treated at our clinic between 1977 and 1990 were reviewed to determine the importance of infections as a cause of death. The total number of infections was 203 (49.5%). A microbiologically documented infection was detected in 27.3%, a clinically documented infection in 9.5% and a possible infection in 12.7% of the patients. Gram-positive bacteria were responsible for 25.9%, gram-negative bacteria for 31.3%, anaerobic bacteria for 2.7%, viruses for 4.5% and fungi for 25.9% of the microbiologically documented infections. Of 29 systemic fungal infections only 2 were diagnosed before the patients died. The remaining diagnoses rested on autopsy findings. Empiric antifungal therapy was introduced in 1983; still, 74.2% of systemic fungal infections in 1977-1990 were detected after 1982. Patients with a verified infection had statistically significantly higher CRP concentrations than patients who died of other causes (152 mg/l vs. 117.5 mg/l, p = 0.018). We conclude that infection is a significant cause of death in patients with these diseases. The number of systemic fungal infections is increasing, despite the widespread use of antifungal medication and thus better diagnostic methods and more effective treatment are needed.     

Distinguishing schizophrenic patients from healthy controls by quantitative measurement of eye movement parameters

BACKGROUND: Eye tracking dysfunction is a putative trait marker for susceptibility to schizophrenia; however, it cannot be recommended as an additional tool for the diagnosis of schizophrenia, due to low sensitivity and specificity. METHODS: To assess the diagnostic potentials of combinations of eye movement paradigms, four smooth pursuit experiments (1: constant velocity of 15 degrees/sec; 2 and 3: combination with either visual or auditory distractors; 4: constant velocity of 30 degrees/sec) and two saccadic eye movement experiments (1: reflexive saccades; 2: voluntary saccades) were conducted. Fourteen patients with residual schizophrenia and 17 healthy controls were studied. Two sets of discriminant analyses (each with the resubstitution and with the "leaving one out" method) were calculated. RESULTS: In the first set, all 10 characteristic variables were included, whereas for the second set, the three most powerful parameters were selected (two from smooth pursuit tasks and one from a voluntary saccade experiment). This procedure provided the best classification results, regarding concordance between clinical diagnoses and eye movement dysfunction (kappa = .67-.80). CONCLUSIONS: Schizophrenic patients of the residual subtype can be differentiated from healthy individuals with considerable criterion validity on the basis of paradigms from two different ocular motor systems.     

Reducing the threat: an experiential exercise to introduce role play to student nurses

OBJECTIVE: To determine if cervical smears obtained with an Ayre spatula and a cytobrush are better detectors of atypia and dysplasia than the modified Ayre spatula alone, as determined by a 2-year clinical follow-up study. METHOD: Paired cervical samples were obtained, one using a modified Ayre spatula and the other a cytobrush. In those smears with any abnormality, follow-up after 2 years documented subsequent cytologic and/or histologic diagnosis. The statistical relationship between the screening tests and follow-up cytologic diagnosis was investigated. SETTING: Seven hundred ninety-two women, aged 18 years and older, who presented to a family practice residency clinic for Papanicolaou tests. RESULTS: The correlation coefficient for the diagnoses obtained using the modified Ayre spatula and the clinical follow-up was .40 (P = .0008), while the correlation coefficient between the cytobrush samples and the clinical follow-up diagnoses was .25 (P = .04). The kappa statistics indicate statistically significant concordance only between the spatula and the follow-up diagnoses. CONCLUSIONS: Cervical smears obtained with a modified Ayre spatula correlated significantly with the follow-up diagnoses. As cervical sampling tools emerge, they need to be evaluated on the basis of accurate identification of significant clinical disease, not only on the basis of obtaining endocervical cells to avoid unnecessary repetition of screening tests and diagnostic workups.     

Perception of causes of omissions in the assessment of patients with chest pain

There is growing evidence that errors and omissions often occur in the nursing assessment and care of patients. As yet, the impact of audit has been insufficient to correct these deficiencies, possibly because audit does not primarily focus on the causes of deficiencies. The purpose of this study was to examine the perceived causes of omissions in the assessment of patients with chest pain and to compare these with omissions detected in an audit of the assessment records. The type of attributions nurses used to explain the causes of the omissions was also investigated. Following an audit of the assessment records of patients with chest pain, 88 nurses were invited to answer a 51-item questionnaire relating to the types of omissions which occurred in the assessment of patients with chest pain. The results showed a marked discrepancy between the frequency of reported omissions and those found in the assessment records. The most common causes of omissions reported by the nurses were patients' condition, work overload, lack of time, poor assessment documentation, not realizing that the assessment had not been fully carried out and different nurses being involved in the assessment of patients. Nurses overwhelmingly attributed the causes of omissions to external or environmental factors rather than internal ones such as lack of knowledge or fatigue, which have implications for the types of strategies that might be used to improve care.     

The effects of race and information variance on disagreement between psychiatric emergency service and research diagnoses in first-episode psychosis

BACKGROUND: Previously, we reported that patient race was associated with disagreement between research and clinical diagnoses. To extend this work, we studied whether disagreement was specifically due to associations of patient race with information or criterion variance. METHOD: Ninety-nine patients consecutively admitted through the University of Cincinnati Psychiatric Emergency Service (PES) for a first hospitalization for psychosis were evaluated using the Structured Clinical Interview for DSM-III-R. Diagnoses made in the PES were compared with those obtained from the structured interview. We examined the contributions of information variance and criterion variance to the association between race and diagnostic agreement of PES and research diagnoses. RESULTS: Agreement in PES and research diagnoses was present in only 42% of patients. Diagnostic agreement was less common in non-white patients than white patients, even after controlling for other sociodemographic and clinical variables. Information variance was the cause of diagnostic disagreement in 58% of cases and was associated with patient race. Criterion variance, occurring in 42% of cases, was not associated with race. CONCLUSION: Patient race may contribute to the diagnostic process in the psychiatric emergency service by influencing the information obtained from patients during clinical evaluations.     

Imaging findings in patients with-right lower quadrant pain: alternative diagnoses to appendicitis

Patients with right lower quadrant (RLQ) pain referred for imaging studies with a clinical diagnosis of appendicitis may have other pathologic conditions mimicking appendicitis. Appropriate diagnostic imaging may establish other specific diagnoses and thereby play a significant role in determining proper medical or surgical treatment. In this pictorial essay, we present a spectrum of imaging findings in patients whose clinical features were suggestive of appendicitis, but the diagnoses of a broad spectrum of other diseases were established with the imaging studies. The differential diagnoses of diseases mimicking appendicitis are reviewed.     

Forced oscillation technique for the evaluation of severe sleep apnoea/hypopnoea syndrome: a pilot study

The forced oscillation technique (FOT) is a noninvasive method of potential clinical interest for quantitatively assessing airway mechanics during sleep. We investigated the applicability of FOT as a diagnostic tool for noninvasive assessment of airflow obstruction in patients with sleep apnoea/hypopnoea syndrome (SAHS) during sleep. In seven patients previously diagnosed with severe SAHS (mean+/-SD apnoea/ hypopnoea index (AHI) 67+/-14) we performed a full polysomnography (PSG) together with on-line measurement of respiratory impedance (IZI) using FOT. For each patient we determined: 1) number of respiratory events conventionally detected by full PSG, those obtained by FOT and their degree of concordance; and 2) the characteristics and values of IZI during the respiratory events. FOT was well tolerated and easily applied in conjunction with a conventional sleep setup. The mean number of respiratory events x h(-1) detected by PSG and FOT were 55+/-16 and 58+/-17, respectively, with a strong concordance. IZI increased from a baseline of 11+/-4 to 50+/-20 cmH2O x L(-1) x s during apnoea (mean+/-SD). In all but one patient intermittent increases of IZI occurred immediately before each obstructive apnoea. In four patients, the increases of IZI developed at end-expiration whereas in two others occurred during inspiration. During hypopnoea most of the patients showed decreases of IZI during expiration. In conclusion, forced oscillation technique can be used as a noninvasive and complementary tool for the diagnosis of respiratory events and provides an on-line quantitative approach for continuous monitoring of airflow obstruction during sleep in patients with sleep apnoea/hypopnoea syndrome.     

Clinical recognition of pulmonary embolism: problem of unrecognized and asymptomatic cases

Dyspnea, pleuritic chest pain, and tachypnea are widely appreciated as common initial features of pulmonary embolism (PE). This knowledge is derived primarily from prospective studies evaluating diagnostic tests or therapeutic interventions in which the study patients are suspected to have PE based on their initial symptoms. Autopsy studies, however, continue to show that most cases of fatal PE are unrecognized and undiagnosed. Data from studies screening for PE in patients with deep venous thrombosis and in postoperative patients suggest that many patients with PE are asymptomatic and that PE is unrecognized. We believe that the current concepts regarding the initial clinical features of PE are too narrow and biased toward symptomatic cases. High clinical suspicion may be insufficient in recognizing PE. Herein we summarize the available data and explore the implications for clinical practice.     

Recent advances in skeletal-muscle-based gene therapy

OBJECTIVE: To determine the sensitivity and specificity of postmortem dementia diagnoses based on a retrospective informant interview by comparison with criterion standard neuropathological diagnoses and the results of previous clinical examinations. SETTING: Three university-based academic research centers. SUBJECTS: Fifty-four deceased elderly persons with Alzheimer disease, another dementing disorder, a neurologic disease resulting in functional impairment but no dementia, or no neurologic disorder. METHODS: Blinded nonclinician interviewers administered the Dementia Questionnaire (DQ) by telephone to informants, typically close relatives, who were familiar with the intellectual and functional status of the subjects before death. Two senior clinicians (LJ.T. and C.K.) rated each DQ for the presence or absence of a dementia syndrome during life and for the specific disorders causing the dementia, if present. Raters were blinded to the neuropathological findings and based their assessments only on data provided by responses to the DQ. Comparison was made with diagnoses based on neuropathological assessment. In most cases, the results of antemortem clinical examinations were also available as a check on the clinical diagnosis of the dementia syndrome. Sensitivity and specificity of the DQ diagnoses were computed, and chance-corrected agreement measures were calculated for the 2 independent DQ raters (LJ.T. and C.K.). RESULTS: Compared with antemortem clinical diagnosis, the average sensitivity of the DQ for the clinical syndrome of dementia was 92.8%, the specificity was 89.5%, and the interrater agreement was 98% (kappa = 0.96). Among 7 subjects with mild dementia (Mini-Mental State Examination score > or = 24 at the last clinical examination), 5 (71%) were correctly identified using the DQ. The DQ correctly indicated the absence of dementia in 8 (80%) of 10 subjects with other neurologic disorders causing functional impairment. Compared with the neuropathological diagnoses, the DQ differentiated Alzheimer disease from other primary causes of dementia with a sensitivity of 89% and a specificity of 72%. The interrater agreement was 93.8% (kappa = 0.85). CONCLUSIONS: Compared with the results of the antemortem clinical examinations, the DQ was sensitive to the presence of dementia, detected most cases of mild dementia, and discriminated dementia from other neurologic disorders causing functional impairment. Compared with the neuropathological diagnoses, the ability of the DQ to differentiate Alzheimer disease from other dementing disorders indicates that it may be useful as a research tool.