4.Effect of magnitude and duration on the performance of Cumulative Sum
Ding-Lun ZHOU ; Wei-Zhong YANG ; Ya-Jia LAN ; Zhong-Jie LI
Chinese Journal of Epidemiology 2012;33(6):617-621
To explore the effect of magnitude and duration on the performance of Cumulative Sum (CUSUM),with simulation method used on the subject after the insertion of 11 outbreak events into baseline data with Poisson distribution.Sensitivity fluctuated from 9.1% to 100.0% with specificities higher than 98.6%.Sensitivity was significantly correlated with magnitude,and increased along with the increase of magnitude.However,no significant correlation was observed between sensitivity and duration.A magnitude which was at least 2.6 times higher than that of the mean daily baseline could result in the sensitivity of 100.0%.Time-lag would be improved along with the increase of magnitude.Time between onset and detection of an outbreak was no longer than one day when magnitude was more than 1.8 of the mean daily baseline.In summary,the performance of CUSUM was influenced by magnitude,but not by duration.CUSUM had the advantage of good time-lag and high sensitivity when the outbreak magnitude was more than 2.4 time over the baseline data.
5.Evaluation of hematology analyzer in determination of CRP
Jia-Xin YUE ; Hong-Xia WANG ; Yu-Long CONG ; Ya-Ting LAN ;
Chinese Journal of Laboratory Medicine 2003;0(07):-
Objective To evaluate the performance of the ABX Micro C-reactive protein(CRP)in determination of CRP.Methods The analytic characteristics including precision,carry-over,linearity, stability,interference and comparability were examined.Results The coefficient of variation(CV)was less than 5.1%,10% and d.3% for within-run,between-run and between-day,respectively.Carryover was less than 1.2%.Whole blood samples held at either room temperature or 4℃ were stable for 48 hours with relative deviation less than 6.0% relatively.Linear range was 1.0-70.0 mg/L using undiluted samples.The comparison between the ABX Micro CRP and Behring Nephelometer Ⅱ was well correlated Both serum:Y=0.996 7X-0.398 5,r~2=0.965 9;serum for BN Ⅱ,whole-blood samples for the ABX Micro CRP:Y=0.908 8X-0.138 2,r~2=0.959 4;both serum and whole-blood samples for the ABX Micro CRP: Y=1.001 7X-0.898 2,r~2=0.952 7.No obvious interference was observed by hyperhemoglobinemia and hyperlipidemia.Conclusion The determination of CRP test with ABX Micro is accurate and reliable.
6.Study on mental workload of teachers in primary schools.
Yuan-mei XIAO ; Zhi-ming WANG ; Mian-zhen WANG ; Ya-jia LAN ; Guang-qin FAN ; Chang FENG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2011;29(12):930-932
OBJECTIVETo investigate the distribution characteristics and influencing factors of mental workload of teachers in primary schools.
METHODSNational Aeronautics and Space Administration-Task Load Index (NASA-TLX) was used to assess the mental workload levels for 397 teachers of primary schools in a city.
RESULTSThe mental workload (64.34+10.56) of female teachers was significantly higher than that (61.73+ 9.77) of male teachers (P<0.05). The mental workload (65.66+10.42) of "-35" years old group was the highest. When age of teachers was younger than 35 years old, there was a positive correlation between the mental workload and age (r=0.146, P<0.05). When age of teachers was older than 35 years old, there was a negative correlation between the mental workload and age (r=-0.190, P<0.05). The teachers with higher education level felt higher mental workload (unstandardized coefficients B=1.524, standardized coefficients /=0.111, P<0.05). There was a positive correlation between the mental workload and working hours per day (unstandardized coefficients B =4.659, standardized coefficients/3 =0.223, P<0.001).
CONCLUSIONMental workload of the teachers in primary schools is closely related to age, educational level and work hours per day. Work hours per day is an important risk factor for mental workload. Reducing work hours per day (8 hours) is an effective measure of alleviating the mental workload of teachers in primary schools.
Adolescent ; Adult ; Aged ; Faculty ; Female ; Humans ; Male ; Middle Aged ; Schools ; Stress, Psychological ; epidemiology ; Surveys and Questionnaires ; Workload ; psychology ; Young Adult
7.Appraisal of occupational stress and its influential factors in nurses.
Xin-wei YANG ; Zhi-ming WANG ; Mian-zhen WANG ; Ya-jia LAN
Chinese Journal of Industrial Hygiene and Occupational Diseases 2004;22(2):119-121
OBJECTIVETo assess the occupational stress and its influential factors in nurses.
METHODSA test of occupational stress, its influential factors, work ability were carried out for 248 nurses and 319 controls with revised occupational stress inventory (OSI-R) and work ability index (WAI).
RESULTSThe scores of personal cope resource (131.266 +/- 17.176) and work ability index (32.581 +/- 3.158) in nurse group were significantly higher than those in control group (126.931 +/- 19.108, 31.840 +/- 4.069) (P < 0.05). The main occupational stressors scores (role insufficiency, role clash, and responsibility) in nurses were higher than those in controls (P < 0.05). The stress response of interpersonal relationship in nurses was also higher. The items of personal cope resource, such as recreation, self-care and social support of nurses were superior to those of controls (P < 0.05). Stress response was positively correlated with occupational role (r = 0.512, P < 0.01), and negatively correlated with the personal cope resource (r = -0.475, P < 0.01). The primary influential factors of personal stress were recreation, social support, rational conduct, role insufficiency, role clash, responsibility, and poor work environment.
CONCLUSIONTo strengthen social support, to improve work condition for nurses, so as to reduce the occupational stress and to enhance the work ability of nurses are important task in occupational health field.
Humans ; Multivariate Analysis ; Nurses ; psychology ; Occupational Health ; statistics & numerical data ; Risk Factors ; Social Support ; Stress, Psychological ; prevention & control ; psychology ; Surveys and Questionnaires ; Workload ; psychology
8.Correlation between chirp auditory brainstem response and behavioral hearing threshold in children.
Xiao-ya WANG ; Ren-zhong LUO ; Jun LAN ; Rui-jin WEN ; Yu ZOU ; Jia-lin ZHOU
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2009;44(3):188-191
OBJECTIVETo investigate the correlation between thresholds in the chirp-ABR and behavior audiogram in order to find out if it is possible to be used as an clinical application of the chirp-ABR in estimating hearing sensitivity.
METHODSTwenty-two cases with hearing loss or normal hearing were enrolled in the study. The behavior audiogram and the response thresholds of chirp ABR (including chirp ABR, L-chirp ABR and U-chirp ABR) were obtained from 35 ears.
RESULTSTwenty-two cases were of both genders. The age was between 3.3- 6.5-years-old with the average age of 4.8-years-old. Divided by the degree of hearing loss, in the 35 ears, there were 6 with normal hearing, 2 with slightly hearing loss, 4 with moderate hearing loss, 10 with severe hearing loss and 13 with profound hearing loss. The Pearson correlation coefficients were 0.939, 0.900 and 0.930, respectively, which got from the data between the average of 0.5 - 4 kHz and chirp ABR respond threshold, 0.5 kHz and L-chirp ABR, and the average of 1 - 4 kHz and U-chirp ABR.
CONCLUSIONAs an objective test, the response threshold of chirp-ABR and the behavior audiogram were a highly correlated with each other, but more application in more subjects is needed.
Acoustic Stimulation ; Audiometry, Evoked Response ; Auditory Threshold ; physiology ; Child ; Child Behavior ; Child, Preschool ; Evoked Potentials, Auditory, Brain Stem ; physiology ; Female ; Hearing Tests ; Humans ; Male
9.The appraisal of reliability and validity of subjective workload assessment technique and NASA-task load index.
Yuan-mei XIAO ; Zhi-ming WANG ; Mian-zhen WANG ; Ya-jia LAN
Chinese Journal of Industrial Hygiene and Occupational Diseases 2005;23(3):178-181
OBJECTIVETo test the reliability and validity of two mental workload assessment scales, i.e. subjective workload assessment technique (SWAT) and NASA task load index (NASA-TLX).
METHODSOne thousand two hundred and sixty-eight mental workers were sampled from various kinds of occupations, such as scientific research, education, administration and medicine, etc, with randomized cluster sampling. The re-test reliability, split-half reliability, Cronbach's alpha coefficient and correlation coefficients between item score and total score were adopted to test the reliability. The test of validity included structure validity.
RESULTSThe re-test reliability coefficients of these two scales and their items were ranged from 0.516 to 0.753 (P < 0.01), indicating the two scales had good re-test reliability; the split-half reliability of SWAT was 0.645, and its Cronbach's alpha coefficient was more than 0.80, all the correlation coefficients between its items score and total score were more than 0.70; as for NASA-TLX, both the split-half reliability and Cronbach's alpha coefficient were more than 0.80, the correlation coefficients between its items score and total score were all more than 0.60 (P < 0.01) except the item of performance. Both scales had good inner consistency. The Pearson correlation coefficient between the two scales was 0.492 (P < 0.01), implying the results of the two scales had good consistency. Factor analysis showed that the two scales had good structure validity.
CONCLUSIONBoth SWAT and NASA-TLX have good reliability and validity and may be used as a valid tool to assess mental workload in China after being revised properly.
Adolescent ; Adult ; Aged ; Female ; Humans ; Male ; Mental Competency ; Middle Aged ; Occupational Health ; Reproducibility of Results ; Sampling Studies ; Self-Assessment ; Surveys and Questionnaires ; standards ; Task Performance and Analysis ; Workload
10.TNF-α and IL-1RA polymorphisms and silicosis susceptibility in Chinese workers exposed to silica particles: a case-control study.
Yong Wei WANG ; Jia Ya LAN ; Lin Yue YANG ; Jun Wang DE ; Jie KUANG
Biomedical and Environmental Sciences 2012;25(5):517-525
OBJECTIVETo assess the association of TNF-α and IL-1RA SNPs with the risk of silicosis in Chinese workers exposed to silica particles.
METHODSCase-control study design was used to enroll 68 silicotic patients induced by silica particles and 68 healthy workers matched for length of silica particle exposure as controls. Both cases and controls were from the same company in southwest China, and each of them was requested to complete a questionnaire. Blood samples were drawn for genomic DNA extraction from each participant. The genotyping of TNF-α (-238 and -308) and IL-1RA (+2018) was performed using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) and SYBR green-based quantitative polymerase chain reaction (qPCR), respectively. Unconditional logistic regression model was used to estimate odds ratios (ORs) and their 95% confidential intervals (CI) for SNPs.
RESULTSNo significant differences were found between cases and controls in particles exposure length, body mass index (BMI), and status of smoking and alcohol consumption except for age (P=0.001) and blood type (P=0.042). The frequencies of TNF-α (-238) and IL-1RA (+2018) genotypes in cases were significantly different from those in controls, (P=0.001 and P=0.002, respectively), while a borderline significant difference was found in the frequencies of TNF-α (-308) between cases and controls (P=0.063). The variants of three SNPs increased the risk of silicosis in the Chinese workers exposed to silica particles. The adjusted ORs of TNF-α (-308), TNF-α (-238) and IL-1RA (+2018) were 2.8 (95% CI: 1.1-7.5), 20.9 (95% CI: 1.8-236.4) and 4.0 (95% CI: 1.6-10.1), respectively.
CONCLUSIONIt is suggested that cytokine polymorphisms of TNF-α (-238, -308) and IL-1RA (+2018) are associated with the risk of silicosis in the Chinese workers exposed to silica particles. Further independent studies on the interaction between SNPs and exposure to silica particles with a larger sample size are therefore warranted.
Adult ; Asian Continental Ancestry Group ; Case-Control Studies ; Genetic Predisposition to Disease ; Genotype ; Humans ; Interleukin 1 Receptor Antagonist Protein ; genetics ; metabolism ; Logistic Models ; Male ; Middle Aged ; Odds Ratio ; Polymorphism, Genetic ; Silicon Dioxide ; toxicity ; Silicosis ; genetics ; Tumor Necrosis Factor-alpha ; genetics ; metabolism