Reliability and validity of the Japanese version of the Work Limitations Questionnaire in employees of multiple private companies.

OBJECTIVE: Previous studies reported that presenteeism costs the enterprises more than absenteeism. It becomes more important for corporate management to evaluate the outcomes of health promotion initiatives for their employees using work performance scales in Japan. We previously developed a Japanese version of Work Limitations Questionnaire (WLQ-J), a presenteeism scale developed by Lerner D. et al., and conducted an internet survey to examine the reliability and validity of WLQ-J with 710 employees from an IT company and a medical institution as subjects and reported the study results (Ida et al, 2012). The objective of the present study is to examine the reliability and validity of WLQ-J with employees from more companies and industries than those included in the previous study. METHODS: We analyzed for 4,440 employees from 14 companies and 9 industries as subjects, who were selected from a total of 4,712 employees who answered both WLQ-J and Brief Job Stress Questionnaire (BJSQ) on the internet or paper survey conducted from September 2014 to January 2015. RESULTS: The subjects' average age was 40.3±11.8 years (33.2±9.5 years in the previous study), with the percentage of males and females being 77.9% and 21.1%, respectively. The factor structure of WLQ-J accorded with that of the original version of WLQ. This supports the factorial validity of WLQ-J. In addition, sufficient internal consistency was recognized by Cronbach's alpha of the whole scale (0.87 for the present study and 0.97 for the previous study) and the subscales (0.77-0.94 for the present study and 0.88-0.95 for the previous study). The four subscale scores of WLQ-J were significantly correlated with the stress response of BJSQ with correlation coefficients of 0.28-0.64 for the present study and 0.39-0.60 for the previous study (p < 0.01 for both studies). Moreover, criterion-related validity of WLQ-J was also supported by the significant dose-response relationship between the subscale scores of WLQ-J and stress response of BJSQ (p < 0.01 for the previous study and p < 0.001 for the present study). CONCLUSIONS: The present study demonstrated the reliability and validity of WLQ-J in a population of employees from more companies and industries than those in the previous study, with its average age and percentage of males and females close to those of the whole Japanese industries. This suggests that WLQ-J is available as a stable scale for presenteeism in different populations in Japan.

[Development of the Work Limitations Questionnaire Japanese version (WLQ-J): fundamental examination of the reliability and validity of the WLQ-J].

OBJECTIVE: It is reported that presenteeism costs more than absenteeism. However, it is difficult to measure presenteeism in Japan because there are few available instruments. We examined the reliability and validity of the Japanese version of the Work limitations Questionnaire (the WLQ-J). METHODS: We conducted an internet survey with the WLQ-J and Brief Job Stress Questionnaire (BJSQ) of 1,545 males and females working for an IT company and a medical institution (21-61 years of age). The number of employees of the IT company and nursing staff of the medical institution included in the analysis were 373 and 337, respectively (effective response rate: 46.0 %). RESULTS: The subjects' average age and the ratio of females were 33.2 ± 9.5 yr old and 60.3%, respectively. Factor analysis showed that the number of factors and items of subscales of the WLQ-J accorded with those of the original WLQ. This supports the factorial validity of the WLQ-J. Additionally, sufficient internal consistency was recognized by Cronbach's alpha (the whole scale=0.97, the subscales=0.88-0.95). Criterion-related validity was supported by the significant dose-response relationship between the subscale scores of the WLQ-J and the stress response of BJSQ as an external criterion (p<0.01). CONCLUSIONS: The study results demonstrate the reliability and validity of the WLQ-J. It is expected that human resource functions such as senior management, personnel affairs, line management, and occupational health staff over a wide range of industries will use the WLQ-J. Further studies are needed to verify the reliability and validity of the WLQ-J by examining differences in the WLQ-J arising from gender, age, industry, and occupation between multiple studies, and by finding relationships between the WLQ-J and other evaluation scales.

Relationship between stress and performance in a Japanese nursing organization.

PURPOSE: The purpose of this paper is to describe the relationship between job stress, stress coping ability and performance among Japanese nurses. DESIGN/METHODOLOGY/APPROACH: Health risk and organization environment as job stress factors, sense of coherence (SOC) as stress coping ability and medical risk indicator and sickness-absence days as a performance proxy were used to investigate the relationship between stress and performance. Length of professional experience also was included in the investigation. FINDINGS: The findings suggest a possibility that enriching nurses' professional experiences reduces medical risk. There is also a possibility that raising the SOC, while improving organization environment, contributes to reducing sickness-absence. RESEARCH LIMITATIONS/IMPLICATIONS: A cross-sectional study of nurses in a single institution was used. In order to generalize the study's results, it will be necessary to conduct multi-institutional longitudinal studies. ORIGINALITY/VALUE: The present study shows key factors affecting medical risk and sickness-absence leading to a reduced nursing performance.

Use of an artificial neural network to localize accessory pathways of Wolff-Parkinson-White syndrome with 12-lead electrocardiogram.

Today, radio-frequency ablation has been shown to be a safe and effective method to treat paroxysmal tachycardia with Wolff-Parkinson-White syndrome. The many criteria reported for localizing the sites of accessory pathways from a 12-lead electrocardiogram have not proven adequate to differentiate the correct sites of accessory pathways for all situations. This study trained an artificial neural network to differentiate the varied features needed to localize 10 sites of accessory pathways. One hundred fifty patients underwent successful catheter ablation, with manifest single and antegradely conducting accessory pathways. Using the two electrocardiogram features of polarity of delta wave and R wave's share of QRS complex, an artificial neural network learned the characteristics of electrocardiogram waves for each site of the 10 accessory pathways through 90 learning cases, and an applicable network model was developed for testing. In 58 of 60 test cases (96.7%), sites of accessory pathways were localized correctly by the network. Based on the method employed in the present study, it thus becomes possible to predict the sites of accessory pathways with Wolff-Parkinson-White syndrome in more detail by using an artificial neural network with a 12-lead electrocardiogram. In the future, when this method is incorporated into a conventional automatic electrocardiogram system which could analyze delta waves and ORS complex, it will become useful to automatically diagnose the locations of the accessory pathways with Wolff-Parkinson-White syndrome in clinical practice.