The validity of different multiple comparison correction methods in the analysis of brain function image data / 中华行为医学与脑科学杂志

Objective@#To explore the effectiveness of different multiple comparisons correction methods by comparing the detection rate and false positive rate of brain activation analysis using functional magnetic resonance imaging (fMRI) data.@*Methods@#On the basis of task-based fMRI dataset (including low-intensity and high-intensity stimuli condition, n=20) and resting-state fMRI dataset(n=32), brain activation results were corrected by multiple comparsion correction methods in SPM and SnPM13 software, and the activation detection rate and false positive rate were compared with different correction methods.@*Results@#Voxel-or peak-based correction methods had relatively low false positive rate.When P<0.05 after correction, the proportion of the subjects with false-positive were 0.19 and 0.16, and the number of false-positive voxels were 404 and 2 448, respectively.But the two methods had low detection rate, which were more suitable for detecting strong activation.While cluster-based correction methods had relative high detection rate and high false positive rate.When P<0.05 after correction, the proportion of the subjects with false-positive were 0.34 and 0.38, and the number of false-positive voxels were 7 870 and 8 320, respectively.And thus they were more suitable for detecting weak activation. Group-level analysis could effectively reduce false positive rate.@*Conclusion@#In practice, researchers should choose a suitable correction method based on their specific research objectives and data to achieve a balance between the detection rate and false positive rate.

The validity of different multiple comparison correction methods in the analysis of brain function im-age data / 中华行为医学与脑科学杂志

Objective To explore the effectiveness of different multiple comparisons correction methods by comparing the detection rate and false positive rate of brain activation analysis using functional magnetic resonance imaging ( fMRI) data. Methods On the basis of task-based fMRI dataset ( including low-intensity and high-intensity stimuli condition,n=20) and resting-state fMRI dataset( n=32),brain acti-vation results were corrected by multiple comparsion correction methods in SPM and SnPM13 software,and the activation detection rate and false positive rate were compared with different correction methods. Results Voxel-or peak-based correction methods had relatively low false positive rate. When P<0. 05 after correction,the proportion of the subjects with false-positive were 0. 19 and 0. 16,and the number of false-pos-itive voxels were 404 and 2 448,respectively. But the two methods had low detection rate,which were more suitable for detecting strong activation. While cluster-based correction methods had relative high detection rate and high false positive rate. When P<0. 05 after correction,the proportion of the subjects with false-posi-tive were 0. 34 and 0. 38,and the number of false-positive voxels were 7 870 and 8 320,respectively. And thus they were more suitable for detecting weak activation. Group-level analysis could effectively reduce false positive rate. Conclusion In practice,researchers should choose a suitable correction method based on their specific research objectives and data to achieve a balance between the detection rate and false positive rate.

Simulation analysis of 9033 cases of second trimester maternal serum screening for Down's syndrome / 解放军医学杂志

Objective To reduce the screening positive rate (SPR) and improve clinical efficiency of maternal serum screening for Down's syndrome.Methods Nine thousand and thirty-three cases of second trimester maternal serum screening for Down's syndrome were included from Apr.2013 to Apr.2014 in the present study.The screening results,all basic data and equation curves were analyzed retrospectively.Based on the data from the authors' laboratory,the important adjustment parameters were simulated.Combined with postnatal follow-up results,the quality and clinical performance of second trimester serum screening for Down's syndrome were evaluated.Results The SPR of second trimester serum screening for Down's syndrome was 6.69％(604/9033),the detection rate (DR) was 75％(3/4),and FPR was 6.65％(601/9033).The median multiple of median (MOM) of alpha-fetoprotein (AFP) was low and SPR was high,and MOM of free human chorionic gonadotropin β subunit (free hCGβ) were high and SPR was high,while MOM of unconjugated estriol (uE3) were a little bit low,and SPR was slightly high.Considering these three factors,it is believed that the screening positive rate is high.By the simulation adjustments of MOM value equations (AFP and free hCGβ) and weight correction equation,the SPR reduced to 4.11％(371/9033) after recalculating the risk,FPR declined to 4.07％(368/9033),and no more Down's syndrome fetus were missed compared with postnatal follow-up results.Conclusion Based on a localized setting depending on the local laboratory data,we suggest that the MOM value distributions(AFP,free hCGβ and uE3) and maternal weight should be regularly adjusted since it is a useful way to reduce the false-positive rate and improve clinical efficiency of maternal serum screening for Down's syndrome.

Formulation and evaluation on Sysmex XN9000 blood cell analyzer re-examination criteria in ISO15189 accredited laboratory / 国际检验医学杂志

Objective To establish the re-examination criteria of the Sysmex XN-9000 automatic blood cell analyzer pipeline suitable for this laboratory for ensuring the accuracy of detection results .Methods A total of 2250 whole blood samples were se-lected from inpatients ,outpatients and subjects undergoing physical examination .The Sysmex XN-9000 blood cell analyzer was a-dopted to conduct the detection .With the manual microscopic examination as the golden standard ,26 items of re-examination criteria were performed the verification and evaluation .The positive predicting value ,negative predicting value ,false positive rate ,false neg-ative rate and re-examination rate were performed by the statistics .Results In compariing the instrument alarm information with the microscopic examination results ,the positive predicting value was 91 .59% ,the negative predicting value was 98 .64% ,the false positive rate was 2 .09% ,the false negative rate was 1 .02% and the re-examination rate was 24 .84% .Conclusion The formulated re-examination criteria of the Sysmex XN-9000 blood cell analyzer is in accord with the characteristics of our laboratory ,which in-creases the detection efficiency ,prevents the missing detection and false detection and has clinical guidance significance .

Analyze of the False Positive Rate of Serum Anti Treponema Pallidum Specific Antibody of 26 707 Cases Detected by Chemiluminescence Method / 现代检验医学杂志

Objective To detect serum anti-Treponema pallidum specific antibody of 26 707 cases by Abbott I2000SR auto-matic chemiluminescent microparticle immunoassay analyzer,and treponema pallidum particle agglutination assay (TPPA) was regarded as a standard reference method which was used to detect anti-Treponema pallidum specific antibody.To analyze the false positive rate of Abbott I2000SR according to the TPPA.Methods Collected 26 707 serums from inpatients and outpatients of the hospital during September 1,2013 to March 5,2014.The subjects were asked to fasting conditions taking venous blood 3 ml,3 000 r/min centrifugal 10 min utes after the separation of serum,detected the Anti-TP by CMIA (Ab-bott I2000SR)and the TPPA testing,analyzed test results by statistical methods.Results There were 52 cases detected by I2000SR whose S/CO values of 26 707 cases of serum Treponema pallidum specific antibodies were 1 to 2,of which 9 cases were verified positive by TPPA,and the positive rate was 17.31%.There were 26 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 2 to 3,of which 9 cases were verified positive by TPPA,and the posi-tive rate was 34.62%.There were 26 cases detected by I2000SR whose S/CO values of Treponema pallidum specific anti-bodies were 3 to 5,of which 9 cases were verified positive by TPPA,and the positive rate was 34.62%.There were 25 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 5 to 7,of which 11 cases were veri-fied positive by TPPA,and the positive rate was 44%.There were 25 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 7 to 10,of which 17 cases were verified positive by TPPA,and the positive rate was 68%.There were 28 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 10to 13,of which 24 cases were verified positive by TPPA,and the positive rate was 85.71%.There were 23 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 13 to 17,of which 20 cases were verified posi-tive by TPPA,and the positive rate was 86.96%.There were 24 cases detected by I2000SR whose S/CO values of Trepone-ma pallidum specific antibodies were 17 to 21,of which 22 cases were verified positive by TPPA,and the positive rate was 91.67%.There were 29 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were 21 to 26,of which 28 cases were verified positive by TPPA,and the positive rate was 96.55%.There were 104 cases detected by I2000SR whose S/CO values of Treponema pallidum specific antibodies were above 26,of which 104 cases were verified posi-tive by TPPA,and the positive rate was 100%.The total number of positive cases were 364,of which 254 were positive ca-ses,the positive rate was 69.78%.False positive rate was 0.42% and positive predictive value was 69.78%.Conclusion Abbott I2000SR automated chemiluminescent microparticle immunoassay analyzer has the feature of automated detection, closed reagents,simple operation,speed,and more accurate results and so on.Although high sensitivity but its results have false positive,so cannot diagnose based on the results of Abbott I2000SR,and need use of the TPPA to test and corroborate.

Analysis of the Effects of Different Disinfectants on Results of Antibiotics Skin Test / 中国药房

OBJECTIVE:To analyze the effects of different disinfectants on results of antibiotics skin test,and to improve the accuracy of the judgment results of antibiotics skin test. METHODS:1 500 patients undergoing antibiotics skin test of penicillin and cephalosporin were randomly divided into group A and group B with 750 patients in each group. Group A was given 75% etha-nol disinfection,and group B was given iodine disinfection. The incidence of false positive results were compared after disinfected with 2 kinds of disinfectants. RESULTS:The incidence of false positive result in group B was lower than in group A,with statisti-cally significant difference (χ2=10.004,P<0.05). CONCLUSIONS:For skin disinfection of antibiotics skin test,iodine is better and safer than 75%ethanol.

The Evaluation of Integrated Test as an Antenatal Screening Test for Down's Syndrome in Korea

BACKGROUND: Antenatal screening for Down's syndrome has been developed and improved over the past 20 yr. Recently, integrated test, which combines the first and second trimester markers has shown the highest detection rate (DR) and lowest false positive rate (FPR) among Down's syndrome screening tests currently in use. The purposes of this study were to evaluate the screening performance of integrated test and to compare the results with triple test studies in Korea. METHODS: The study population consisted of Korean pregnant women who underwent triple or integrated test between April 2005 and December 2008. Triple test was performed using measurements of alpha-fetoprotein (AFP), unconjugated estriol (uE3), and human chorionic gonadotropin (hCG) in the second trimester. Integrated test was performed using nuchal translucency (NT) by ultrasonography and pregnancy-associated plasma protein A (PAPP-A) from maternal serum in the first trimester, and AFP, uE3, hCG, and inhibin-A in the second trimester. The screening performance of each test was evaluated by DR and FPR. RESULTS: Twenty-seven Down's syndrome pregnancies were confirmed in women screened by triple (N=6,736) or integrated test (N=7,688). At 1:100, 1:270, and 1:300 of risk cutoff, triple test showed 45%, 73%, and 73% of DR and 4.7%, 11.2%, and 12.4% of FPR, respectively. At 1:100, 1:150, and 1:300 of risk cutoff, integrated test showed 63%, 69%, and 75% of DR and 1.5%, 1.9%, and 3.0% of FPR, respectively. CONCLUSIONS: Integrated test showed higher DR and lower FPR, demonstrating better screening performance than triple test.

Accuracy of Cervical Pap Smear / 대한부인종양콜포스코피학회잡지

BACKGROUND: Carcinoma of the uterine cervix is a theoretically preventable disease because its precursor lesions can be detected by cervical Papanicolau smears and appropriately treated, Although cervical cytology screening programmes have resulted in the redution of cervical cancer incidence and mortality, Pap smear have been subjected to intense scrutiny and criticism in recent years. The focus of criticism has been the false-negative Pap smear, and the false-negative Pap smear is the major quality issue currently facing the physicians. To reduce the false-negative rate of Pap smear, it is essential to improve the accuracy of Pap smear. But false-negative rate of Pap smear has been reported variously. OBJECTIVE: This study was undertaken to evaluate accuracy of Pap smear by study false-negative and false-positive rate of Pap smear and to determine whether false-negative and false-positive rate had any correlations with clinical factors. STUDY DESIGN: The study population was comprised of 346 women, who were undertaken gynecologic operation at the Department of Obstetrics & Gynecology at Hanyang University hospital between March, 1997 and April, 1998. All patients were taken Pap smear before operation. In 93 women of these, preoperative diagnosis were cervical intraepithelial neoplasia and carcinoma in situ of uterine cervix, and in 253 women of these, preoperative diagnosis were benign disease as uterine myoma or adenomyosis, etc. All of their surgical specimen were examined. Pap smear, pathology, medical charts of all patients were reviewed retrospectively, and false-negative rate and false-positive rate were calculated. Clinical factors that associated with false-negative and false-positive rate were evaluated. Fishers exact test and Pearson chi-square test were used of statistical analysis, RESULTS: False-negative rate of Pap smear was 7.2%, false-positive rate was 4.6%, corresponding rate with histology was 88.2%. Sensitivity and specificity of PAP smear were 87.0% and 97.0% respctively. According to gross finding of uterine cervix, erosion was 46.6% in cervical intraepithelial neoplasia, 67.8% in carcinoma in situ, 66.6% in microinvasive carcinoma of uterine cervix and 55.3% of 103 erosion findings was cervical intraepithelial neoplasia, carcinoma in situ or microinvasive carcinoma. 23.1% of cervical lesion were normal gross finding. Menopause was associated with false-negative rate and previous vaginal infection history, previous cervical minor operation, delivery mode, contraception method, pelvic inflammatory disease history, vaginal bleeding at Pap smear and gross finding of cerbix were not associated. There were no clinical factors that were associated with false-positive rate. CONCLUSION: Compared with other reports, false-negative rate(7.2%) and false-positive rate(4.6%) of Pap smear was lower and corresponding rate(88.2%) was higher in Hanyand university hospital. Because of higher false-negative rate in menopausal women, it need more careful to take and interpretate Pap smear in these group.

A Cytopathologic Analysis of Percutaneous Transthoracic Needle Aspiration Cytology of the Lung: A Six-year Correlation Study in 322 Cases / 대한세포병리학회지

In a six-year period (from May 1988 to April 1994), fine needle aspiration cytology (FNAC) of 322 pulmonary lesions from 296 patients were performed at Soonchunhyang University Hospital. Of these 322, malignancy was diagnosed cytologically in 139 (43.2%), suspicious malignancy in 7 (2.2%), negative in 164 (50.8%), and insufficient material in 12 (3.8%). Malignant lesion consisted of 54 cases of adenocarcinoma, 50 cases of squamous cell carcinoma, 18 cases of small cell carcinoma. They were verified by histologic confirmation in 70 cases. There were 2 (0.6%) false positive cases due to florid bronchoalveolar hyperplasia and atypical bronchial epithelial cells associated with granulomatous lesion. Overall accuracy rate was 90%, the sensitivity 84.3% and the specificity 94.7%.

Re-evaluation of TSH screening test in neonates

Five years ago, we made the cut-off value of Tsh by dry filter paper method as 15 microU/ml to sereening congenital hypothyroidism. Since then, 1,210 term neonates, who had no perinatal problems, were born in SNUCH between Aug. 1987 and Apr. 1992, had been performed this neonatal Tsh screening test with this cut-off point. Neonates had been recalled for measurement of serum T4/TSH to rule out congenital hypoothyroidism if their TSH value by screening tests reveal more than 15 microU/ml. Because there had been high false-positive rate during 5 years, we felt thiscut-off value of TSH should be set higher than 15 microU/ml with same method. Therefore, we analyzedthis TSH values to set a new cut-off point to recall the neonates. The results ars asbelow: 1) TSH value by dry filter paper method was 8.48+/-4.41 U/ml(mean+/-S.D.) 2) Assuming 15 microU/ml as a cut-off point for recall the neonates, the false positive fate is 8.01% 3) Tomake the false positive rates as 0.3%, it is reasonable to set the cut-off point at 22 microU/ml, whichis +/-3S.D.(99.7 percentile) of measured TSH level by dry filter paper method.

Reliability Indexes of Automated Perimetric Tests

The "reliability" of a subject's automated perimetric result is generally assessed by three measures: fixation loss, false positive and false negative rates. These reliability indicies were examined for 237 glaucomatous and ocular hypertensive eyes who for the first time underwent visual field testing (central 30-2 test on Humphrey visual field analyzer. Allergan Humphrey). Of the examination results, 11% of subjects were considered unreliable with the use of the manufacturer's reliability criteria. 71% of the unreliable results were due to failure to meet the criterion for fixation loss. The rest 29% were due to high false negative rates. After given reinstruction and more attention to fixation loss throughout the test by the technician, second visual field test was performed. On second examination, 82% of fixation loss and 71% of false negative rate was reduced.