[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.