Validity of the Cognitive Behavioral Driver's Inventory in predicting driving outcome.

OBJECTIVE: This study seeks to (a) compare Cognitive Behavioral Driver's Inventory (CBDI) scores for clients who passed and failed a driving evaluation and for diagnostic groups (left cerebrovascular accident [CVA], right CVA, traumatic brain injury [TBI], and cognitive decline); (b) determine sensitivity, specificity, and positive and negative predictive values of the CBDI; (c) compare validity of the CBDI with other tools; and (d) identify factors associated with outcome. PARTICIPANTS: This historical cohort study included clients with neurological conditions who completed a driving evaluation. MEASURES: CBDI, Motor-Free Visual Perception Test (MVPT), Bells test, and driving results were extracted from the charts. RESULTS: Mean CBDI (p < 0.0001) and MVPT (p < 0.0001) scores were significantly worse for those failing compared to passing the driving evaluation. Sensitivity of the CBDI was 62%, specificity was 81%, positive predictive values were 73%, and negative predictive values were 71%. Results varied according to diagnostic group. CONCLUSIONS: The CBDI is not sufficiently predictive of outcome to replace a driving evaluation, and is predictive only for clients with R-CVA and TBI. Evaluation of driving should vary according to diagnosis.     

Validity,reliability and predictive accuracy of the Driving Awareness Questionnaire

Purpose.?To examine the psychometric properties of the Driving Awareness Questionnaire (DriveAware) and to compare this rating of awareness of driving ability with the rating made in the context of an on-road assessment.

Method.?A prospective design was employed to examine the psychometric properties of DriveAware using Rasch analysis. Participants (n = 91) with varying diagnoses were recruited from two driving rehabilitation centres in Sydney, Australia. They completed DriveAware in the context of a standard driving assessment. Awareness of driving ability determined by DriveAware was compared with awareness determined in the on-road assessment.

Results.?Rasch analysis provided good evidence for construct validity and inter-rater reliability and some evidence for internal reliability of DriveAware. The item hierarchy was logical and goodness-of-fit statistics for four of five items were within an acceptable range. The test had a moderate reliability index (0.73). Measurement precision could be improved by including more items to assess drivers with little awareness. When compared with the on-road measure of awareness, the best DriveAware cut-off score yielded sensitivity of 84% and specificity of 94%.

Conclusion.?This short and easy-to-administer test could provide a useful tool with sound psychometric properties to measure awareness of driving ability.     

Occupational therapy assessment of open-road driving performance: validity of directed and self-directed navigational instructional components.

OBJECTIVE: The purpose of this study was to validate an assessment tool used by occupational therapists to evaluate on-road driving performance. METHODS: The driving assessment was conducted over a 15-km route that consisted of a range of traffic situations and contained both directed and self-directed navigational instruction. The driving performance of four groups of drivers of different ages and visual characteristics was assessed independently by an occupational therapist and driving instructor using a range of scoring criteria. RESULTS: The occupational therapist scores were significantly affected by the drivers' age and visual characteristics (directed navigation, F(3,133) = 6.05, p = 0.001; self-directed navigation, F(3,133) = 5.04, p < 0.002), and these group differences were greater for self-directed navigational instruction. The occupational therapist scores were highly correlated with the driving instructor's global driver safety rating (r = 0.76, p < 0.001). DISCUSSION: The driving assessment instrument was a valid measure of on-road driving performance relative to an independent global driving safety evaluation. The instrument provided detailed information regarding driving performance and highlighted areas of difficulty, particularly when drivers followed self-navigational instruction.     

Predicting Fitness to Drive in People With Cognitive Impairments by Using DriveSafe and DriveAware

Kay LG, Bundy AC, Clemson LM. Predicting fitness to drive in people with cognitive impairments by using DriveSafe and DriveAware.

Objectives

To examine the psychometric properties of DriveSafe and DriveAware and their predictive validity.

Design

Prospective study compared screening tests with criterion standard.

Setting

Two driving rehabilitation centers affiliated with a university and a geriatric rehabilitation facility.

Participants

Consecutive sample of drivers with functional impairments (n=115) and subgroup of drivers with cognitive impairments (n=96) referred for a driving assessment.

Interventions

Not applicable.

Main Outcome Measure

Driving performance was measured by a standardized assessment in real traffic.

Results

Rasch analysis provided evidence for construct validity and internal reliability of both tests. Tests trichotomized drivers into unsafe, safe, and further testing categories. The optimal lower cutoff identified unsafe drivers with a specificity of 97% (95% confidence interval [CI], 83-100) in the test sample and 96% (95% CI, 80-100) in the validation sample. The optimal upper cutoff identified safe drivers with a sensitivity of 93% (95% CI, 77-99) and 95% (95% CI, 76-100), respectively.

Conclusions

By using DriveSafe and DriveAware, drivers with cognitive impairments referred for a driving assessment can be categorized as unsafe, safe, or requiring further testing, with only 50% needing an on-road assessment. Before clinical practice is changed, these findings should be replicated.     

Development of the Adelaide driving self-efficacy scale

OBJECTIVE: To describe the development of the Adelaide Driving Self-Efficacy Scale (ADSES) and to report on its reliability and validity. METHODS: A set of 12 driving behaviours, developed through literature review, clinical experience and expert review, were rated for self-efficacy using a Likert scale. Internal consistency was investigated using a Cronbach's alpha coefficient and construct validity by comparing ADSES scores of stroke and non-stroke drivers. Criterion-related validity was examined by comparing ADSES scores with the result on a standardized on-road assessment. SETTING: A rehabilitation hospital in Adelaide, South Australia. PARTICIPANTS: Staff from the hospital and stroke patients from the rehabilitation unit. Data from a non-stroke sample (n -/ 79) and stroke patients (n -/ 81) were used to test internal consistency and construct validity. A separate group of 45 people recommended for a driving assessment, of whom 34 were stroke patients, were used to test criterion validity. RESULTS: Cronbach's alpha coefficient was 0.98, indicating high internal consistency. The non-stroke and stroke groups showed significant differences in ADSES scores (t(158)-/ 5.5, P B < 0.05), demonstrating construct validity. Differences in ADSES scores for those participants who passed or failed the on-road assessment were significant for both the entire driving assessment group (t(43)-/ 3.2, P B < 0.05) and the stroke subgroup (t(43)-/ 3.2, P B < 0.05), indicating criterion validity. CONCLUSION: The ADSES has demonstrated internal consistency and construct validity with the stroke and non-stroke population. The scale demonstrated criterion validity in its relationship with outcome of an on-road driving assessment. It appears to be a reliable and valid measure of driving self-efficacy.     

计算机辅助检测和诊断系统对甲状腺结节细针穿刺活检的评估价值

目的探讨计算机辅助检测和诊断（CAD）系统评估甲状腺结节是否应行细针穿刺活检的临床应用价值。 方法收集2019年2月至10月哈尔滨医科大学附属第一医院106例欲行细针穿刺活检的甲状腺结节,进行CAD系统、高年资、低年资超声医师评估并按照美国甲状腺学会指南建议穿刺与否,以细针穿刺活检病理结果为“金标准”进行判读。若病理结果为恶性,则判定建议细针穿刺活检有意义;若病理结果为良性,则判定建议细针穿刺活检无意义,分别计算3种方式的敏感度、特异度、阳性预测值、阴性预测值和准确性,比较3种方式的评估效能;按照结节大小将其分为3组：1.0 cm~＜1.5 cm组、1.5 cm~＜2.0 cm组和≥2.0 cm组,研究其对CAD软件评估甲状腺结节穿刺与否这一效能的影响,比较不同组的敏感度、特异度和准确性的差异。3种方式间及各组间差异的比较均采用McNemar检验法。 结果CAD软件的评估效能与高年资医师相对比,CAD软件的敏感度低,而特异度高,差异均有统计学意义（71.2% vs 84.6%,P=0.039;77.8% vs 61.1%,P=0.049）;CAD软件的评估效能与低年资医师相对比,其敏感度、特异度均高于低年资医师,差异均有统计学意义（71.2% vs 55.8%,P=0.021;77.8% vs 64.8%,P=0.039）;CAD软件的评估准确性与高年资医师相近,但大于低年资医师（74.5% vs 60.4%）,差异有统计学意义（P=0.001）。CAD软的评估效能与结节大小有关,当结节最大直径为1.0 cm~＜1.5 cm时,CAD软件的敏感度最高（82.4% vs 40.0% vs 62.5%）,差异具有统计学意义（P=0.027）;当结节最大直径≥2.0 cm时,CAD软件具有最高的特异度及准确性（91.7% vs 80.0% vs 53.3%;84.4% vs 81.6% vs 48.0%）,差异均具有统计学意义（P=0.023、0.002）。 结论CAD系统能对甲状腺结节给出合理的细针穿刺活检建议,其评估准确性与高年资医师相近且高于低年资医师,结节大小能影响其评估效能。     

Visual testing for readiness to drive after stroke: a multicenter study

OBJECTIVE: The purpose of this study was to determine the ability of a visual-perception assessment tool, the Motor-Free Visual Perception Test, to predict on-road driving outcome in subjects with stroke. DESIGN: This was a retrospective study of 269 individuals with stroke who completed visual-perception testing and an on-road driving evaluation. Driving evaluators from six evaluation sites in Canada and the United States participated. Visual-perception was assessed using the Motor-Free Visual Perception Test. Scores range from 0 to 36, with a higher score indicating better visual perception. A structured on-road driving evaluation was performed to determine fitness to drive. Based on driving behaviors, a pass or fail outcome was determined by the examiner. RESULTS: The results indicated that, using a score on the Motor-Free Visual Perception Test of < or =30 to indicate poor visual-perception and >30 to indicate good visual perception, the positive predictive value of the Motor-Free Visual Perception Test in identifying those who would fail the on-road test was 60.9% (n = 67/110). The corresponding negative predictive value was 64.2% (n = 102/159). Univariate logistic regression analyses revealed that older age, low Motor-Free Visual Perception Test scores and a right hemisphere lesion contributed significantly to identifying those who failed the on-road test. CONCLUSIONS: The predictive validity of the Motor-Free Visual Perception Test is not sufficiently high to warrant its use as the sole screening tool in identifying those who are unfit to undergo an on-road evaluation.     

Prospective Validation of a Modified Thrombolysis In Myocardial Infarction Risk Score in Emergency Department Patients With Chest Pain and Possible Acute Coronary Syndrome

Objectives: This study attempted to prospectively validate a modified Thrombolysis In Myocardial Infarction (TIMI) risk score that classifies patients with either ST‐segment deviation or cardiac troponin elevation as high risk. The objectives were to determine the ability of the modified score to risk‐stratify emergency department (ED) patients with chest pain and to identify patients safe for early discharge. Methods: This was a prospective cohort study in an urban academic ED over a 9‐month period. Patients over 24 years of age with a primary complaint of chest pain were enrolled. On‐duty physicians completed standardized data collection forms prior to diagnostic testing. Cardiac troponin T‐values of >99th percentile (≥0.01 ng/mL) were considered elevated. The primary outcome was acute myocardial infarction (AMI), revascularization, or death within 30 days. The overall diagnostic accuracy of the risk scores was compared by generating receiver operating characteristic (ROC) curves and comparing the area under the curve. The performance of the risk scores at potential decision thresholds was assessed by calculating the sensitivity and specificity at each potential cut‐point. Results: The study enrolled 1,017 patients with the following characteristics: mean (±SD) age 59.3 (±13.8) years, 60.6% male, 17.9% with a history of diabetes, and 22.4% with a history of myocardial infarction. A total of 117 (11.5%) experienced a cardiac event within 30 days (6.6% AMI, 8.9% revascularization, 0.2% death of cardiac or unknown cause). The modified TIMI risk score outperformed the original with regard to overall diagnostic accuracy (area under the ROC curve = 0.83 vs. 0.79; p = 0.030; absolute difference 0.037; 95% confidence interval [CI] = 0.004 to 0.071). The specificity of the modified score was lower at all cut‐points of >0. Sensitivity and specificity at potential decision thresholds were: >0 = sensitivity 96.6%, specificity 23.7%; >1 = sensitivity 91.5%, specificity 54.2%; and >2 = sensitivity 80.3%, specificity 73.4%. The lowest cut‐point (TIMI/modified TIMI >0) was the only cut‐point to predict cardiac events with sufficient sensitivity to consider early discharge. The sensitivity and specificity of the modified and original TIMI risk scores at this cut‐point were identical. Conclusions: The modified TIMI risk score outperformed the original with regard to overall diagnostic accuracy. However, it had lower specificity at all cut‐points of >0, suggesting suboptimal risk stratification in high‐risk patients. It also lacked sufficient sensitivity and specificity to safely guide patient disposition. Both scores are insufficiently sensitive and specific to recommend as the sole means of determining disposition in ED chest pain patients. ACADEMIC EMERGENCY MEDICINE 2010; 17:368–375 © 2010 by the Society for Academic Emergency Medicine     

Evaluation of fitness to drive. The physician's role in assessing elderly or demented patients

The role of physicians in deciding whether a patient should continue to drive is purely advisory. However, physicians have a moral and, in some states, a legal obligation to report patients who are no longer fit to drive. The most authoritative test to predict safe driving in the elderly is an on-road evaluation conducted by the state driver's licensing authority, which has ultimate responsibility for deciding a patient's fitness to drive. Patients with mild dementia are generally considered safe drivers, although specialized testing, such as an on-road test, may be indicated. Those with moderate dementia can be further evaluated by the on-road test, since psychological testing to distinguish moderate from mild dementia is imprecise. Severe dementia is generally considered a contraindication to driving. When a patient is deemed unfit to drive, the physician can provide counseling and support to help ease the transition away from driving.     

Predictive value of foot pressure assessment as part of a population-based diabetes disease management program

OBJECTIVE: To evaluate the effectiveness of dynamic plantar pressure assessment to determine patients at high risk for neuropathic ulceration. In choosing the cut point, we looked for an optimum combination of sensitivity and specificity of plantar pressure to screen for neuropathic ulceration. RESEARCH DESIGN AND METHODS: A total of 1,666 consecutive individuals with diabetes (50.3% male) presenting to a large urban managed care-based outpatient clinic were enrolled in this longitudinal 2-year outcome study. Patients received a standardized medical and musculoskeletal assessment at the time of enrollment, including evaluation in an onsite gait laboratory. RESULTS: Of the entire population, 263 patients (15.8%) either presented with or developed an ulcer during the 24-month follow-up period. As expected, baseline peak plantar pressure was significantly higher in the ulcerated group than in the group who did not ulcerate (95.5 +/- 26.4 vs. 85.1 +/- 27.3 N/cm(2), P < 0.001). There was also a trend toward increased pressure with increasing numbers of foot deformities, as well as with increasing foot risk classification (P = 0.0001). Peak pressure was not a suitable diagnostic tool by itself to identify high-risk patients. After eliminating patients without loss of protective sensation, using receiver operating characteristic (ROC) analysis, the optimal cut point, as determined by a balance of sensitivity and specificity, was 87.5 N/cm(2), yielding a sensitivity of 63.5% and a specificity of 46.3%. CONCLUSIONS: The data from this evaluation continue to support the notion that elevated foot pressure is an important risk factor for foot complications. However, the ROC analysis suggests that foot pressure is a poor tool by itself to predict foot ulcers.     

Improving Driving Performance of Senior Drivers Through Self-Monitoring with a Driving Diary

This study investigated whether self-monitoring of driving by use of driving diaries would improve driving performance in senior drivers. Forty-seven drivers (20 male, 27 females) aged 59 to 87 (mean age = 71.3, SD = 7.4) completed 30 consecutive daily driving diaries assessing driving performance and dangerous events while driving, as part of a larger study. It was incidentally noted that the reported driving of many subjects appeared to be improving over time. Therefore, diary entries for the first four days were compared to the last four days to assess whether this improvement was statistically significant. Paired t-tests revealed significant (p < 0.05) improvements in: maintaining steady speed; keeping up with traffic; maintaining lane position; and a trend toward decreased drifting out of lane (p = .056). McNemar Change Test revealed a significant (p < 0.05) decrease in the number of subjects encountering dangerous events (i.e., turning the wrong way in one-way situations, slamming on brakes, near collisions, or collisions). On the other hand, subjects reported rolling through stop signs with a fairly high frequency, which did not decrease over time (p = .4), supporting the veracity and consistency of diary reports. Self-monitoring of driving through use of driving diaries rapidly improved reported driving performance and reduced dangerous driving events in this sample of senior drivers. This finding was quite unexpected and it needs replication. Use of this simple and inexpensive intervention may help to significantly reduce motor vehicle accidents and injuries among senior drivers.     

Driving skills in elderly persons with stroke: comparison of two new assessment options

OBJECTIVE: To compare the effectiveness of two methods of assessing off-road driving skills that claim to predict on-road driving fitness of persons with stroke. METHOD: Fifty-six persons with stroke (age 44 to 82 yrs; mean, 60.2 yrs) completed the 2 off-road driving assessments along with standard clinical and on-road driving tests. MAIN OUTCOME MEASURES: Linear stepwise regression on 4 variables of the Dynavision Performance Assessment Battery (DPAB), the Cognitive Behavioral Driver's Inventory (CBDI) variable (composite score), and the variables of age, gender, and lesion side. RESULTS: A 4-minute endurance subtest from the DPAB was superior to the CBDI in predicting success/failure in the on-road driving test (75%). However, success on both the 4-minute endurance subtest from the DPAB and the CBDI tests significantly improved the prediction of on-road success. If participants passed the CBDI and the endurance test from the DPAB, they also passed the on-road assessment. CONCLUSION: Driving fitness of elderly persons with stroke can be assessed with reasonable accuracy using off-road tests, minimizing the expense and risk associated with on-road assessments in this population.     

基于计算机辅助诊断技术的超声图像处理软件对甲状腺结节诊断效能的初步研究

目的通过比较基于计算机辅助诊断技术（CAD）的甲状腺超声图像处理软件（安克侦）与超声医师对甲状腺结节进行甲状腺影像报告和数据系统（TI-RADS）评分的差别,初步探讨安克侦CAD软件在甲状腺结节良恶性鉴别诊断中的价值。 方法选取2015年5月至2016年10月就诊于中山大学附属肿瘤医院的194例甲状腺结节患者的病例资料。每个病例选取一个结节进行分析,所有结节均经手术或超声引导下细针穿刺活检（US-FNA）病理证实。由两位年资不同的超声医师评估结节图像,分别对结节的5个特征（成分、回声、形态、边缘、强回声）进行评分,得出总的TI-RADS评分并分类。安克侦CAD软件则通过自动分析结节图像,得出基于美国放射学会（ACR）标准的TI-RADS评分。 结果安克侦CAD软件的TI-RADS评分与高年资医师比较,差异无统计学意义（Z=0.964,P=0.335）,与低年资医师比较,差异具有统计学意义（Z=5.593,P<0.001）。以TR5为恶性诊断界值,安克侦CAD软件的诊断敏感度与高年资医师比较,差异无统计学意义（84.62% vs 86.54%,P=0.815）,且其略高于低年资医师,但差异无统计学意义（84.62% vs 73.08%,P=0.052）。安克侦CAD软件、低年资医师、高年资医师评分的诊断特异度分别为65.56%、87.78%、82.22%,安克侦CAD软件明显低于低年资和高年资医师（65.56% vs 87.78%,χ²=12.893,P<0.01;65.56% vs 82.22%,P=0.004）。CAD软件的ROC曲线下面积均低于高年资及低年资医师（0.735 vs 0.921,Z=4.537,P<0.0001;0.735 vs 0.898,Z=4.033,P=0.0001）。 结论安克侦CAD软件对甲状腺结节的诊断敏感度与高年资及低年资医师相比,并无显著差异,但诊断特异度及诊断准确性均低于高年资及低年资医师。其综合诊断效能仍需进一步深入研究。     

Preliminary report of the clinical performance of a new urinary bladder cancer antigen test: comparison to voided urine cytology in the detection of transitional cell carcinoma of the bladder

We compared the ability of a new urinary bladder cancer antigen (UBC) test with conventional cytology for the detection of transitional cell carcinoma of the bladder using voided urine samples. The UBC was measured and corrected for the creatinine concentration in the urine of 61 patients with transitional cell carcinoma of the bladder (group 1), 23 patients without recurrent bladder tumors during follow-up (group 2), 28 patients with benign prostatic hyperplasia (group 3), nine patients with prostate cancer (group 4), and 90 healthy volunteers free of urological diseases (group 5). The UBC concentrations were 408.8+/-578.5, 18.8+/-26.6, 23.9+/-32.7, 17.5+/-18.6 and 4.6+/-6.7 ngmg(-1) creatinine (mean+/-S. D.) for groups 1-5, respectively. The level for group 1 was significantly higher than for any other group. The sensitivity and specificity, which were optimized using receiver-operating characteristic curves for groups 1 and 2 were 82.0% and 82.6%, respectively, at a threshold value of 39 ngmg(-1) creatinine. The sensitivity and specificity of cytology for these same groups were 60.7% and 86.9%, respectively. The sensitivity of the UBC was significantly higher than that of cytology, not only for total bladder tumors (82.0% vs. 60.7%, P<0.02) but also for grade I transitional cell carcinoma of the bladder (76.5% vs. 11.8%, P<0. 001). While offering a similarly high specificity, the UBC test might have an advantage over cytology in terms of superior sensitivity, particularly for low-grade tumors.     

Sensitive noninvasive marker for the diagnosis of probable bacterial or viral infection

Urinary trypsin inhibitor (uTi) is a product of elastase-mediated degradation of interleukin-alpha-inhibitor (I-alpha-I). Its activity increases in the urine of patients with a malignancy, inflammation, or infection, or in late pregnancy. The objective of this study was to compare the sensitivity of uTi in urine with that of serum quantitative C-reactive protein (CRP) for diagnosing infection, as indicated by white cell response and clinical assessment. Ninety controls and 171 patients with various systemic infections were enrolled. We measured uTi enzymatically on a Cobas Fara (Roche Diagnostics). Patients were separated into bacterial, probable bacterial, viral, or probable viral groups based on the results of a complete blood count with differential (CBC), urinalysis (UA), and clinical assessment. In the bacterial (n=70) and control (n=90) groups, the uTi values (mean+/-SE) were 25.3+/-3.1 mg/L and 2.8+/-0.8 mg/L, respectively. uTi (at 2.7 mg/L) had a diagnostic sensitivity of 91% and specificity of 82% (AUC=0.889), whereas CRP (at a cutoff of 10 mg/L) had a sensitivity and specificity of 82% and 96%, respectively (AUC=0.921). As a marker of infection (positive in both bacterial and viral groups), uTi had a sensitivity of 91% (AUC=0.884) vs. 89% (AUC=0.828) for CRP. Our data indicate that uTi has sufficient clinical sensitivity for screening systemic infections, and may have diagnostic value as a noninvasive test.     

Diagnosis of viable myocardium using velocity data of Doppler myocardial imaging: comparison with positron emission tomography.

To test whether velocity data of Doppler myocardial imaging (DMI) at rest is useful for diagnosis of myocardial viability, 25 consecutive patients (age 64 +/- 10 years) with regional wall-motion abnormalities at the left anterior descending coronary artery territory and left ventricular dysfunction (ejection fraction: 31 +/- 7%) underwent both DMI at rest and positron emission tomography. The peak systolic velocity (Vpeak) and postsystolic thickening (PST) velocity were measured in myocardial segments of left anterior descending coronary artery territory from apical views. A total of 71 segments were classified by positron emission tomography as normal or viable in 38 (group A) and nonviable in 33 (group B). Although Vpeak did not show any difference between groups (1.81 +/- 1.77 vs 1.29 +/- 0.94 cm/s, P =.107), PST velocity was significantly higher in group A (2.48 +/- 1.68 vs 0.89 +/- 0.72 cm/s, P <.001). The sensitivity and specificity of PST velocity > 2.0 cm/s for diagnosis of viability were 61% (23/38) and 97% (32/33), respectively. In segments with PST velocity was < or =2.0 cm/s, Vpeak > 1.8 cm/s could discriminate group A from B with a sensitivity of 67% (10/15) and a specificity of 91% (29/32). The algorithm using both PST velocity and Vpeak of DMI showed sensitivity and specificity of 87% and 88%, respectively, for diagnosis of myocardial viability. Velocity data of DMI at rest provides robust information regarding viability in selected patients, and an advantage of this technique is that no stress testing is needed.     

基于甲状腺成像报告和数据系统分类的计算机辅助诊断系统对甲状腺癌超声诊断的辅助价值

目的探讨基于甲状腺成像报告和数据系统（TI-RADS）分类的计算机辅助诊断（CAD）系统对超声医师诊断甲状腺癌的辅助价值。 方法收集2018年10月至2019年3月在国内5家医院的400例甲状腺结节超声图像进行多中心回顾性研究。采用由北京大学前沿交叉学科研究院研发的基于TI-RADS分类的CAD系统,超声医师诊断甲状腺癌的诊断模式分为无CAD模式和CAD模式,11名具有不同工作经验的超声医师（低年资超声医师4名,中年资超声医师4名,高年资超声医师3名）在上述2种模式下诊断甲状腺癌。比较2种诊断模式的诊断效能及读片时间：绘制CAD系统和超声医师诊断甲状腺癌的受试者工作特征（ROC）曲线,应用DeLong方法比较2种模式下曲线下面积（AUC）的差异;应用配对t检验比较2种模式的读片时间差异。 结果在CAD模式下,所有超声医师诊断甲状腺癌的AUC值较无CAD模式有显著提高［0.848（0.837~0.858） vs 0.800（0.788~0.812）］,差异具有统计学意义（P＜0.001）;敏感度从73.8%（95%CI：71.9%~75.6%）提升到82.7%（95%CI：81.0%~84.3%）,差异具有统计学意义（χ²=9.870,P＜0.001）;特异度从86.2%（84.7%~87.6%）提升到86.9%（85.4%~88.3%）,但差异无统计学意义（χ²=0.021,P=0.379）。进行亚组分析时,在CAD模式下,低年资超声医师和中年资超声医师诊断甲状腺癌的AUC值较无CAD模式有显著提高（0.840 vs 0.740;0.848 vs 0.814）,差异具有统计学意义（P＜0.001、=0.001）,但高年资超声医师诊断甲状腺癌的AUC值较无CAD模式无明显变化（0.859 vs 0.861,P=0.861）。在CAD模式下,所有超声医师的阅片时间较无CAD模式减少［（20.2±8.2）s vs（22.7±9.6）s］,差异具有统计学意义（t=-23.9,P＜0.001）。 结论CAD模式有助于低年资超声医师和中年资超声医师对甲状腺癌的诊断,同时缩短了诊断时间。     

Duplex ultrasonography is an efficient diagnostic tool for the detection of moderate to severe internal carotid artery stenosis

BACKGROUND: The aim of this prospective national multicentre study with 10 participating university and county hospitals was to establish the diagnostic accuracy of carotid duplex sonography in the identification of >or=70% internal carotid artery (ICA) stenosis defined according to European Carotid Surgery Trial (ECST) criteria. METHODS: In 134 patients, aged 69 +/- 9 years, ICA stenoses were identified by routine carotid duplex ultrasonography, confirmed angiographically within 2 months, and graded according to ESCT criteria. The accuracy of carotid duplex to detect ICA stenosis >or=70% was assessed using receiver operating characteristic (ROC) analysis with carotid angiography as a reference. RESULTS: Measurement of peak systolic velocity in ICA (PSV(ICA)) identified ICA stenosis >or=70% with high diagnostic accuracy that was Doppler angle dependent resulting in different optimal PSV(ICA) cut points within the angle range 0 degrees -49 degrees (1 x 7 m s(-1)) and 50 degrees -62 degrees (2 x 3 m s(-1)). The diagnostic discrimination was significantly better when narrow Doppler angles (0 degrees -49 degrees ) were used (P<0 x 01) providing the sensitivity of 98 +/- 2% and specificity of 94 +/- 4%. DISCUSSION: Ultrasound duplex technique identifies moderate to severe (>or=70%) ICA stenoses (ECST criteria) with high degree of accuracy that can be further improved by the use of Doppler angle specific optimal PSV(ICA) cut points.