Detection of malingering on the Luria-Nebraska Neuropsychological Battery: an initial and cross-validation.

A formula for detecting faked LNNB profiles was validated on 68 experimental malingerers and adequately motivated patients matched on education, age, and severity of profile. The formula was then cross-validated on 51 malingerers and 202 patients. The formula yielded a cross-validated 23% false negative rate and a 9% false positive rate, for an overall hit rate of 88%. If normal and profoundly impaired profiles are eliminated from the cross-validation analysis, the false negative rate is 17% and the false positive rate 7%, for an overall hit rate of 91%.     

Revised norms and decision rules for the Luria-Nebraska Neuropsychological Battery, Form II.

All control subjects from a previous Luria-Nebraska Neuropsychological Battery, Form II (LNNB2) normative study were combined with a considerably larger normative sample to produce a composite normative sample of 392 subjects with a mean high school educational level. Revised norms for the LNNB2 were developed based on this sample and were scaled with uniform T-scores to make scale elevations comparable across LNNB2 measures. Differences between the scalewise LNNB2 normative values and published alternatives were highly significant. A critical level and actuarial decision rules for differentiation of normal from neurologically impaired performance level were developed for the LNNB2 using the current empirical norms (86% accuracy with current sample empirical critical level; 89% accuracy with LNNB1 critical level). The normative prediction values of Golden, Purisch, and Hammeke for the LNNB2 were not satisfactory (69% overall, with 45% accuracy among brain damaged sample). There was no significant effect of sex of subject on LNNB2 performance level among the control subjects.     

Detection of malingering on the Halstead-Reitan Battery: a cross-validation.

Using the Halstead-Reitan Battery profiles of 796 people, a formula for the detection of malingering was cross-validated to assess the false positive rate. Subjects included normals, psychiatric cases, and all major types of organics. The formula incorrectly designated 27% of the sample as fakers (i.e., as false positives). Of the 120 head trauma cases, 27 (22.5%) obtained Fake scores, while 93 (77.5%) were correctly assessed as not malingering.     

Modal profiles for the Luria-Nebraska Neuropsychological Battery.

Modal Profile Analysis was used to cluster subjects on the clinical scales of the Luria-Nebraska Neuropsychological Battery, Form I (LNNB). The analysis produced 22 modal profile types, of which seven were replicated in multiple samples of subjects with single criterion diagnoses. Subjects who had been assigned to modal types according to their correlations with the modal profiles were more similar to the modal profile of their assigned groups than to other modal profiles. Assigned subjects were more likely to belong to their assigned group than to other groups and were more similar to other subjects who had been assigned to the same group than to subjects assigned to other groups. Eighty-two percent of subjects in the derivation sample were assigned empirically to a modal profile group; 77% of subjects in a cross-validation sample were assigned to a modal profile group. The discussion focuses on the potential research and clinical use of the modal LNNB profiles.     

Comparison of two Bayesian methods to detect mode effects between paper-based and computerized adaptive assessments: a preliminary Monte Carlo study

ABSTRACT: BACKGROUND: Computerized adaptive testing (CAT) is being applied to health outcome measures developed as paper-and-pencil (P&P) instruments. Differences in how respondents answer items administered by CAT vs. P&P can increase error in CAT-estimated measures if not identified and corrected. METHOD: Two methods for detecting item-level mode effects are proposed using Bayesian estimation of posterior distributions of item parameters: (1) a modified robust Z (RZ) test, and (2) 95% credible intervals (CrI) for the CAT-P&P difference in item difficulty. A simulation study was conducted under the following conditions: (1) data-generating model (one- vs. twoparameter IRT model); (2) moderate vs. large DIF sizes; (3) percentage of DIF items (10% vs. 30%), and (4) mean difference in theta estimates across modes of 0 vs. 1 logits. This resulted in a total of 16 conditions with 10 generated datasets per condition. RESULTS: Both methods evidenced good to excellent false positive control, with RZ providing better control of false positives and with slightly higher power for CrI, irrespective of measurement model. False positives increased when items were very easy to endorse and when there with mode differences in mean trait level. True positives were predicted by CAT item usage, absolute item difficulty and item discrimination. RZ outperformed CrI, due to better control of false positive DIF. CONCLUSIONS: Whereas false positives were well controlled, particularly for RZ, power to detect DIF was suboptimal. Research is needed to examine the robustness of these methods under varying prior assumptions concerning the distribution of item and person parameters and when data fail to conform to prior assumptions. False identification of DIF when items were very easy to endorse is a problem warranting additional investigation.     

Neuropsychological information in the Wechsler Adult Intelligence Scale-Revised.

The relationships among Wechsler Adult Intelligence Scale-Revised profiles (WAIS-R), Luria-Nebraska Neuropsychological Battery (LNNB) profiles and Halstead Retian Neuropsychological Battery (HRNB) profiles were examined in two samples of patients referred for neuropsychological evaluation. Canonical correlation analysis suggested that the average level of WAIS-R profiles was related to the average level and scatter of LNNB profiles, Overall performance on the HRNB was less strongly related to overall performance on the WAIS-R than was the LNNB. Patients who were similar to a WAIS-R modal profile characterized by relative deficits on performance subtests were more likely to be similar to LNNB modal profiles characterized by relative impairments on sensorimotor subtests. Patients who were similar to a WAIS-R modal profile characterized by relative deficits on verbal subtests were more likely to be similar to LNNB modal profiles characterized by relative impairments on either language subtests or conceptual subtests. Patients classified into an HRNB profile type characterized by strengths on the Aphasia Screening subtest were more likely to show strengths on WAIS-R verbal subtests. However, less than 8 % of the total samples could be jointly classified into both the requisite WAIS-R profile clusters and one of the associated LNNB or HRNB profile clusters. WAIS-R subtest profile level may be a useful statistic to screen for neuropsychological deficits, but WAIS-R patterns are essentially useless for neuropsychological screening. Discussion focuses on the role of the WAIS-R in neuropsychological evaluations.     

Determination of mode of ventilation using OSRE

This study classifies the mode of ventilation using respiratory rate, inhaled and exhaled carbon dioxide concentrations in anaesthetised patients. Thirty seven patients were breathing spontaneously (SPONT) and 50 were on a ventilator (intermittent positive pressure ventilation, IPPV). A data-based methodology for rule inference from trained neural networks, orthogonal search-based rule extraction, identified two sets of low-order Boolean rules for differential identification of the mode of ventilation. Combining both models produced three possible outcomes; IPPV, SPONT and ‘Uncertain’. The true positive rates were approximately maintained at 96% for IPPV and 93% for SPONT, with false positive rates of 0.4% for each category and 4.3% ‘Uncertain’ inferences.     

Classification with the Luria-Nebraska neuropsychological battery: an application of cluster and ipsative profile analysis.

A sample of 114 subjects, 23 with predominantly left hemisphere brain damage, 25 with predominantly right hemisphere brain damage, 26 with diffuse brain damage, and 40 with adult learning disability were administered the Luria-Nebraska Neuropsychological Battery (LNNB). The clinical scale data were cluster analyzed and subjected to an ipsative analysis of the cluster profiles. A four cluster solution was utilized. It was found that while stable clusters were produced, they were relatively unrelated to actual diagnoses. The first cluster had a normal mean profile, the second reflected specific language impairment, the third, nonverbal skill, memory, and intellectual impairment and the fourth, generalized impairment. The results were discussed in terms of the capacity of the LNNB to generate meaningful neuropsychological profiles.     

Diagnostic parameters of an odd—even item short-form of the Luria—Nebraska neuropsychological battery

The current study examined the concurrent validity of a new short form of Luria-Nebraska Neuropsychological Battery (LNNB). LNNB profiles of 100 subjects of a mixed brain damaged, psychiatric and normal pool were obtained from previously published sources. Levy corrected correlations among both the odd and even number short-forms with the full test ranged from.81 to.90. For the entire sample, absolute numbers of scales above the critical level, number of cases following within a given range of the critical level, and number of cases within each subscale exceeding the critical level were computed. Chi square values revealed significant differences only for the visual, reading, and memory subscales exceeding the critical level.     

Error rates in reporting prostatic core biopsies

Oxley J D & Sen C
(2011) Histopathology Error rates in reporting prostatic core biopsies 58 , 759–765 Aims: To evaluate the false‐negative and false‐positive error rates both in a screening and a non‐screening population. Methods and results: A total of 4192 prostatic biopsies were reported in a 6‐year period by 15 consultant histopathologists, two of whom had an interest in uropathology and were deemed to be specialists (J.O. and C.S.). All biopsies were reviewed prior to the multidisciplinary team (MDT) meeting. The overall false‐negative rate was 1.7% (screening 2.1%, non‐screening 1.5%). The overall false‐positive rate was 0.5% (screening 0.9%, non‐screening 0.4%). These error rates varied among pathologists, with the false‐negative rate ranging from 0% to 9.3%, and the false‐positive rate ranging from 0% to 3.8%. Conclusion: The false‐negative rate was three times greater than the false‐positive rate, showing that detection of significant pathology is far greater in the negative biopsies. More errors occurred in the screening population than in the non‐screening population. The consultants making the most errors were non‐specialists, but the specialists also made false‐negative errors, suggesting that just using specialist reporting alone would not have eradicated errors.     

The use of the Clinical Interview Schedule for the evaluation of mental health in the aged community

As a part of a survey to study the health and living conditions of the elderly population, a random sample of residents aged 65 and over are examined using the Clinical Interview Schedule (CIS) in order to evaluate their psychiatric status. The aim of this study is to evaluate this standard method of assessment as a case-identification instrument in our country. The schedule was completed by 91 subjects. It is easily administered, easily scored, and economical on time. Its completion rate is high. The weighted total scores (WTS) range from 0 to 48. Using the case criteria defined by Cooper & Schwarz (1982), 27 subjects (30%) are considered cases and 64 (70%) are regarded as non-cases. The sensitivity coefficients for the WTS are examined against the overall severity rating at different cut-off points. The optimum cut-off can be anywhere between 16 and 20 points. The WTS has higher validity coefficients to detect the following diagnostic categories (sensitivity, specificity): normals (100%,-); personality (100%, 92%) and affective disorders (100%, 75%). In general the CIS items are given low ratings. Psychotic symptoms are rarely found in this sample. One main problem arose: the item depersonalization is misunderstood by some patients probably because of interpreting it as an upsetting memory disturbance.     

Fuzzy detection of EEG alpha without amplitude thresholding

Intelligent automated systems are needed to assist the tedious visual analysis of polygraphic recordings. Most systems need detection of different electroencephalogram (EEG) waveforms. The problem in automated detection of alpha activity is the large inter-individual variability of its amplitude and duration. In this work, a fuzzy reasoning based method for the detection of alpha activity was designed and tested using a total of 32 recordings from seven different subjects. Intelligence of the method was distributed to features extracted and the way they were combined. The ranges of the fuzzy rules were determined based on feature statistics. The advantage of the detector is that no alpha amplitude threshold needs to be selected. The performance of the alpha detector was assessed with receiver operating characteristic (ROC) curves. When the true positive rate was 94.2%, the false positive rate was 9.2%, which indicates good performance in sleep EEG analysis.     

Accuracy of clinical diagnosis of lung cancer in Budapest in an institute specializing in chest diseases

Among 250 consecutive autopsies (170 males and 80 females) performed at the Institute of Pulmonology in Budapest in 1996/7, there were 132 deaths in which cancer of the lung/bronchus was deemed to be the underlying cause of death. At autopsy, six cases previously thought to be dying from lung cancer were found to have died from other diseases (false positive rate = 5%). Twelve lung cancer deaths were also found to have been missed, a false negative rate of 9%, which was similar for adenocarcinoma, squamous carcinoma, and small cell carcinoma cases. Our findings confirmed the expectation expressed earlier that death certification of lung cancer would be more accurate in an institute specializing in chest diseases, to which patients had to be fit enough to be transferred, than in two general hospitals in Budapest. Nevertheless, since most cases certified as dying from lung cancer die without the benefits available in the specialized institute, the estimated false negative and positive rates for lung cancer death certification in Hungary remain high, at an estimated 56% and 30%, respectively. The much lower autopsy rates in most other countries than in Hungary points to there being considerable inaccuracy in lung cancer mortality rates internationally.     

有核红细胞采用XN1000血液分析仪计数与人工计数结果比较

目的 Sysmex XN1000b型全自动血细胞分析仪检测的有核红细胞结果的有效性和准确性,通过金标法人工涂片检测进行验证。方法 2017年1月~2017年3月本院经过Sysmex XN1000b型全自动血细胞分析仪检测有核红细胞结果阳性标本213例进行仪器结果与人工涂片结果进行准确性验证,对随机抽取100例有核红细胞结果为零的标本验证阴性符合率验证。结果 采用Sysmex XN1000b型全自动血细胞分析仪计数有核红细胞,真阳性率100.00%,假阳性率2.09%,假阴性率0（＜5%）,真阴性率96.70%,阳性结果符合率97.56%。结论 Sysmex XN1000b型全自动血细胞分析仪检测的有核红细胞计数准确性高,阴阳性符合率好,结果可靠,有核红细胞计数可以作为临床报告项目。     

Cross-validation of the discriminative effectiveness of the Luria-Nebraska Neuropsychological Battery for learning disabled adolescents.

This study was a cross-validation of the discriminative effectiveness and diagnostic accuracy of the Luria-Nebraska Neuropsychological Battery (LNNB). Subjects were a group of 31 LD adolescents and a matched group of 31 non-learning disabled students whose achievement fell within the low average to average range. Multivariate analysis of variance (MANOVA) confirmed that the LNNB was sensitive to group differences in analyses with either the basic or localization scales. Discriminant function analyses with 12 basic scales yielded overall rates of diagnostic accuracy ranging from 87.1% to 98.4%. A classification rule, based on the number of basic scale elevations, yielded 95% overall accuracy. Rates of overall accuracy for the eight localization scales ranged from 82.26% to 85.48% in discriminant function analyses. A classification rule, basedon the number of localization scale elevations, yielded 81% overall accuracy. The significance and accuracy of various indicators of dysfunction were investigated. Implications for the diagnosis of learning disability are discussed     

A wavelet-based algorithm for detecting clustered microcalcifications in digital mammograms.

A computerized scheme to detect clustered microcalcifications in digital mammograms has been developed. Detection of individual microcalcifications in regions of interest (ROIs) was also performed. The mammograms were previously classified into fatty and dense, according to their breast tissue. The most appropriate wavelet basis and reconstruction levels were selected. To select the wavelet basis, 40 profiles of microcalcifications were decomposed and reconstructed using different types of wavelet functions and different combinations of wavelet coefficients. The symlets with a basis of length 8 were chosen for fatty tissue. For dense tissue, the Daubechies' wavelets with a four-element basis were employed. Two methods to detect individual microcalcifications were evaluated: (a) two-dimensional wavelet transform, and (b) one-dimensional wavelet transform. The second technique yielded the best results, and was used to detect clustered microcalcifications in the complete mammogram. When detecting individual microcalcifications by using two-dimensional wavelet transform we have obtained, for fatty ROIs, a sensitivity of 71.11% at a false positive rate of 7.13 per image. For dense ROIs the sensitivity was 60.76% and the false positive rate, 7.33. The areas (A1) under the AFROC curves were 0.33+/-0.04 and 0.28+/-0.02, respectively. The one-dimensional wavelet transform method yielded 80.44% of sensitivity and 6.43 false positives per image (A1=0.39+/-0.03) for fatty ROIs, and 62.17% and 5.82 false positives per image (A1=0.37+/-0.02) for dense ROIs. For the detection of clusters of microcalcifications in the entire mammogram, the sensitivity was 80.00% with 0.94 false positives per image (A1=0.77+/-0.09) for fatty mammograms, and 72.85% of sensitivity at a false positive detection rate of 2.21 per image (A1=0.64+/-0.07) for dense mammograms. Globally, a sensitivity of 76.43% at a false positive detection rate of 1.57 per image was obtained.     

An international collaborative study to assess a set of reference reagents for HIV-1 PCR.

An international collaborative study was performed to evaluate a set of PCR reference reagents for HIV diagnosis. Twenty-six laboratories from 9 countries analysed a proficiency panel of 10 coded DNA samples using the PCR reference reagents and protocols. For comparison, these coded samples were then assessed using a laboratory's own 'in-house' reagents and methodologies. The objectives of the study were: (i) to assess inter-laboratory variation of PCR sensitivity, (ii) to evaluate the DNA 'carryover' problem and frequency of false negative results and (iii) to examine the utility of the complete set of reagents and templates to act as reference preparations for HIV PCR. Using the reference reagents, 46% of laboratories reported no false positive results in any of their assays of the negative controls. The remaining laboratories all reported a false positive result(s) in at least one assay. The overall false positive result rate for the study was 9.3%. In contrast, an overall false negative result rate of 7.4% was observed, with some laboratories recording negative results even for samples containing 10,000 molecules of target DNA. The level of absolute sensitivity may be assessed accurately only from the 12 laboratories that obtained no false positive results. All 12 laboratories detected the sample containing 10 molecules of template DNA and 9 out of the 12 laboratories detected the sample containing 1 molecule. This is in close agreement with the theoretical detection rate based on a statistical probability model for the detection of a single molecule. These characterised reference reagents were at least as sensitive as any of the 'in-house' reagents and methodologies applied, including nested PCR. The complete set of characterised reference reagents is now available for quality control assessment of HIV-1 PCR from the MRC ADP.     

网络依赖诊断量表初步编制

目的：根据项目反应理论（IRT）编制网络依赖诊断量表（DSFIAD）.方法：根据模型制定37个条目,5级评分.总计1831名网络使用者为样本.结果：①在测量误差0.1979水平,选取17个条目组成量表.②条目区分度1.0027-1.6771.③条目程度从1-5级均呈单向递增.④因素分析抽取2个因子,解释70.116%的总方差.⑤DSFIAD与效标显著相关（κ=0.8544）.最佳划界值45,敏感度91%,假阳性率4.1%.结论：DSFIAD条目质量及信效度符合IRT与心理测量学的要求.     

Resolving repeatedly borderline results of Hybrid Capture 2 HPV DNA Test using polymerase chain reaction and genotyping

The Hybrid Capture 2 HPV DNA Test (hc2) (Digene Corporation, Gaithersburg, MD) is at present the only FDA approved assay for routine detection of human papillomavirus (HPV) infections. A significant analytical inaccuracy of the hc2 near to cut-off was reported recently. To address this problem, 240 samples with repeatedly borderline/equivocal/indeterminate hc2 results (samples with repeated RLU/CO values between 0.4 and 4.0) were tested using the PGMY09/PGMY11 consensus PCR and genotyping in order to resolve their high-risk HPV status. All PGMY09/PGMY11 PCR negative samples were tested in addition using CPI/IIg consensus PCR. A false negative rate of 11.3% and false positive rate of 19.1% were recorded in the samples with repeatedly borderline hc2 results. The corresponding hc2 false reactivity rates in 95 samples selected at random which were clearly hc2 negative (samples with RLU/CO values less than 0.4) and 124 samples selected at random which were clearly hc2 positive (samples with RLU/CO values more than 4.0) were 4.2% and 5.6%, respectively. The proportion of hc2 false reactivity increased with proximity to the hc2 cut-off value. According to the results of the present study, the introduction of an hc2 grey-zone and retesting of samples with repeatedly borderline hc2 results by an alternate HPV detection method, such as the PGMY09/PGMY11 consensus PCR and genotyping, is recommended.     

The relationship of age to performance on the Luria-Nebraska Neuropsychological Battery

The effect of age upon the Luria-Nebraska Neuropsychological Battery (LNNB) was studied by administering the LNNB and the Wechsler Adult Intelligence Scale to three groups of subjects: A group aged 17-30, a group aged 50-55, and a group aged 65 and older. No subject had any history of brain pathology or psychotic emotional disturbance. Two of the Luria-Nebraska subtests, the Motor and Visual, showed a significant sex-effect in that males performed better than females. Age was related significantly to performance on 11 of 16 Luria Nebraska subscales; older subjects rather consistently showed poorer performance than younger subjects. When intelligence (i.e., Wechsler IQs) and education were controlled statistically, partial correlations still revealed that age had significant effects upon 13 of 16 Luria-Nebraska subscales. These results closely parallel earlier data that concern age-effects on the Luria-Nebraska Battery.