Psychometric assessment of the Japanese version of the Revised Fibromyalgia Impact Questionnaire: reliability and validity.

AIM: To assess the psychometric properties of the Japanese version of the Revised Fibromyalgia Impact Questionnaire (JFIQR) in fibromyalgia (FM) patients. METHOD: The reliability and validity of the JFIQR were assessed using online data collected from Japanese FM patients. Reliability was evaluated based on test-retest reliability results and internal consistency; validity was evaluated on the basis of concurrent and known-group validity. RESULTS: A total of 105 patients completed the online questionnaire. Intra-class correlation coefficients for test-retest were 0.91 for the JFIQR total score with a range of 0.84-0.90 in three domains: function, overall impact and symptoms. Internal consistency results indicated a Cronbach's alpha of 0.90 for the total score with a range of 0.83 and 0.85 for the domains. Concurrent validity results showed that the total score was correlated to all external criteria (Japanese version of the Fibromyalgia Impact Questionnaire, Fibromyalgia Activity Scale-31, Medical Outcomes Study 36-item Short-Form health survey) from a moderate to strong degree with most indicating a strong correlation. Results of known-group validity showed that the JFIQR total score is capable of discriminating between FM and the other groups, such as rheumatic arthritis and no chronic pain (P < 0.0001 for all pairwise comparisons). CONCLUSION: The current psychometric assessment of the JFIQR demonstrated that it is a reliable and valid questionnaire in Japanese patients with FM. Usefulness of the JFIQR in clinical studies and medical practice for Japanese-speaking populations is expected.

Psychometric Assessment of the Japanese Version of the Zurich Claudication Questionnaire (ZCQ): Reliability and Validity.

PURPOSE: The Zurich Claudication Questionnaire (ZCQ) is a self-administered measure to evaluate symptom severity, physical function, and surgery satisfaction in lumbar spinal stenosis (LSS). The purpose of this study is to assess the psychometric properties of the Japanese ZCQ in LSS patients. METHODS: LSS patients who are scheduled to undergo surgery were recruited from 12 facilities. Responses to several questionnaires, including the Japanese ZCQ; the visual analogue scale (VAS) to evaluate the degree of pain in the buttocks/legs, numbness in the buttocks/legs, and low back pain; the Oswestry Disability Index (ODI); and the SF-36v2, were collected before surgery and again 3 months after surgery (the post-surgery ZCQ was administered twice for test-retest reliability). For reliability, test-retest reliability was evaluated using the intra-class coefficient (ICC) and internal consistency was evaluated using Cronbach's alpha coefficient. Concurrent validity was assessed using Spearman's correlation coefficients between the Japanese ZCQ and other questionnaires. Effect size (ES) and standard response mean were calculated for responsiveness. All analyses were performed individually for the Japanese ZCQ symptom, function, and satisfaction domains. RESULTS: Data from 180 LSS patients were used in this analysis. The ICCs were 0.81, 0.89, and 0.88 and Cronbach's alpha coefficients were 0.78, 0.84, and 0.92 for the Japanese ZCQ symptom, function, and satisfaction domains, respectively. Regarding the concurrent validity, strong correlations (±0.5) were demonstrated between the Japanese ZCQ domains and the VAS leg pain, ODI, and SF-36v2 physical functioning or bodily pain, whereas correlations were approximately 0.3 in scales measuring other symptoms that are less related to symptom, function, or satisfaction domains. ESs showed high values for the ZCQ symptom and function domains (-1.73 for both). CONCLUSIONS: These psychometric assessments demonstrate that the Japanese ZCQ is a psychometrically reliable and valid measure in LSS. The Japanese ZCQ can evaluate both multi-dimensional aspects and the level of surgery satisfaction.

Assessment of psychosocial risk factors for the development of non-specific chronic disabling low back pain in Japanese workers-findings from the Japan Epidemiological Research of Occupation-related Back Pain (JOB) study.

To investigate the associations between psychosocial factors and the development of chronic disabling low back pain (LBP) in Japanese workers. A 1 yr prospective cohort of the Japan Epidemiological Research of Occupation-related Back Pain (JOB) study was used. The participants were office workers, nurses, sales/marketing personnel, and manufacturing engineers. Self-administered questionnaires were distributed twice: at baseline and 1 yr after baseline. The outcome of interest was the development of chronic disabling LBP during the 1 yr follow-up period. Incidence was calculated for the participants who experienced disabling LBP during the month prior to baseline. Logistic regression was used to assess risk factors for chronic disabling LBP. Of 5,310 participants responding at baseline (response rate: 86.5%), 3,811 completed the questionnaire at follow-up. Among 171 eligible participants who experienced disabling back pain during the month prior to baseline, 29 (17.0%) developed chronic disabling LBP during the follow-up period. Multivariate logistic regression analysis implied reward to work (not feeling rewarded, OR: 3.62, 95%CI: 1.17-11.19), anxiety (anxious, OR: 2.89, 95%CI: 0.97-8.57), and daily-life satisfaction (not satisfied, ORs: 4.14, 95%CI: 1.18-14.58) were significant. Psychosocial factors are key to the development of chronic disabling LBP in Japanese workers. Psychosocial interventions may reduce the impact of LBP in the workplace.

Central nervous system effects of the second-generation antihistamines marketed in Japan--review of inter-drug differences using the proportional impairment ratio (PIR)-.

BACKGROUND: Second-generation antihistamines (AHs) have, in general, fewer sedative effects than the first-generation. However, important inter-drug differences remain in the degree of cognitive and/or psychomotor impairment. The extent to which a particular compound causes disruption can be conveniently compared, to all other AHs, using the Proportional Impairment Ratio (PIR). Although the PIR can differentiate the relative impairment caused by individual drugs, there is no indication of the reliability of the ratios obtained. OBJECTIVE: To calculate the PIRs -together with 95% confidence intervals (CIs), as an index of reliability- and compare AHs currently, or soon to be, available in Japan, with respect to their intrinsic capacity to cause impairment. METHODS: Results from studies of cetirizine, desloratadine, ebastine, fexofenadine, levocetirizine, loratadine, mequitazine, and olopatadine were included in the PIR calculations. All data utilised came from crossover studies in healthy volunteers which were randomised and placebo and positive-internal controlled. Existing databases from studies reporting the sedative effects of AHs on objective (speed, accuracy, memory) and subjective (feeling) psychometrics were augmented, via results from suitable studies published after the previous reviews. The null value for a PIR was one. RESULTS: A total of 45 studies were finally included for this review. Of the AHs assessed, fexofenadine, ebastine, and levocetirizine showed a PIR for objective tests of 0. However, only fexofenadine (PIR = 0.49) had an upper limit of the 95% CI of less than 1. Fexofenadine, levocetirizine, desloratadine, olopatadine, loratadine, and mequitazine all had a PIR for subjective ratings of 0, but the upper limits of the 95% CIs were all in excess of 1, although fexofenadine (PIR = 2.57) was the lowest. CONCLUSIONS: The results show that there are differences between second-generation AHs in the extent of sedation produced. However, subjective ratings indicate that patients may not necessarily be aware of this.

Potential risk factors of persistent low back pain developing from mild low back pain in urban Japanese workers.

STUDY DESIGN: Two-year, prospective cohort data from the Japan epidemiological research of occupation-related back pain study in urban settings were used for this analysis. OBJECTIVE: To examine the association between aggravated low back pain and psychosocial factors among Japanese workers with mild low back pain. SUMMARY OF BACKGROUND DATA: Although psychosocial factors are strongly indicated as yellow flags of low back pain (LBP) leading to disability, the association between aggravated LBP and psychosocial factors has not been well assessed in Japanese workers. METHODS: At baseline, 5,310 participants responded to a self-administered questionnaire including questions about individual characteristics, ergonomic work demands, and work-related psychosocial factors (response rate: 86.5%), with 3,811 respondents completing the 1-year follow-up questionnaire. The target outcome was aggravation of mild LBP into persistent LBP during the follow-up period. Incidence was calculated for the participants with mild LBP during the past year at baseline. Logistic regression was used to explore risk factors associated with persistent LBP. RESULTS: Of 1,675 participants who had mild LBP during the preceding year, 43 (2.6%) developed persistent LBP during the follow-up year. Multivariate analyses adjusted for individual factors and an ergonomic factor found statistically significant or almost significant associations of the following psychosocial factors with persistent LBP: interpersonal stress at work [adjusted odds ratio (OR): 1.96 and 95% confidence interval (95%CI): 1.00-3.82], job satisfaction (OR: 2.34, 95%CI: 1.21-4.54), depression (OR: 1.92, 95%CI: 1.00-3.69), somatic symptoms (OR: 2.78, 95%CI: 1.44-5.40), support from supervisors (OR: 2.01, 95%CI: 1.05-3.85), previous sick-leave due to LBP (OR: 1.94, 95%CI: 0.98-3.86) and family history of LBP with disability (OR: 1.98, 95%CI: 1.04-3.78). CONCLUSIONS: Psychosocial factors are important risk factors for persistent LBP in urban Japanese workers. It may be necessary to take psychosocial factors into account, along with physical work demands, to reduce LBP related disability.