Satisfactory cross cultural equivalence of the Dutch WOMAC in patients with hip osteoarthritis waiting for arthroplasty

Background: Cross cultural validity is of vital importance for international comparisons. Objective: To investigate the validity of international Dutch-English comparisons when using the Dutch translation of the Western Ontario and McMaster Universities osteoarthritis index (WOMAC). Patients and Methods: The dimensionality, reliability, construct validity, and cross cultural equivalence of the Dutch WOMAC in Dutch and Canadian patients waiting for primary total hip arthroplasty was investigated. Unidimensionality and cross cultural equivalence was quantified by principal component and Rasch analysis. Intratest reliability was quantified with Cronbach's α, and test-retest reliability with the intraclass correlation coefficient. Construct validity was quantified by correlating sum scores of the Dutch WOMAC, Arthritis Impact Measurement Scales (Dutch AIMS2), Health Assessment Questionnaire (Dutch HAQ), and Harris Hip Score (Dutch HHS). Results: The WOMAC was completed by 180 Dutch and 244 English speaking Canadian patients. Unidimensionality of the Dutch WOMAC was confirmed by principal component and Rasch analysis (good fit for 20/22 items). The intratest reliability of the Dutch WOMAC for pain and physical functioning was 0.88 and 0.96, whereas the test-retest reliability was 0.77 and 0.92, respectively. Dutch WOMAC pain sum score correlated 0.69 with Dutch HAQ pain, and 0.39 with Dutch HHS pain. Dutch WOMAC physical functioning sum score correlated 0.46 with Dutch AIMS2 mobility, 0.62 with Dutch AIMS2 walking and bending, 0.67 with Dutch HAQ disability, and 0.49 with Dutch HHS function. Differential item functioning (DIF) was shown for 6/22 Dutch items. Conclusions: The Dutch WOMAC permits valid international Dutch-English comparisons after correction for DIF

Hearing screening program impact on noise reduction strategies

The objective of this study was to determine the impact of the New South Wales Rural Hearing Conservation Program on the implementation of personal hearing protection (PHP) and noise management strategies among farmers who had participated in this program in New South Wales, Australia. A follow-up survey of a random sample of people screened through the New South Wales Rural Hearing Conservation Program was linked to their baseline data. The use of PHP at baseline was compared to use at follow-up in four specific scenarios: use with non-cabbed tractors, with chainsaws, with firearms, and in workshops. For non-cabbed tractors, the net gain in PHP use was 13.3%; the net gain was 20.8% for chainsaws, 6.7% for firearms, and 21.3% for workshops. Older farmers and those with a family history of hearing loss were less likely to maintain or improve PHP use. Those with severe hearing loss, males, and participants reporting hearing problems in situations where background noise was present were more likely to maintain or improve PHP use. Forty-one percent of farmers had initiated other strategies to reduce noise exposure beyond the use of PHP, which included engineering, maintenance, and noise avoidance solutions. The early (hopefully) identification of hearing deficit in farmers and farm workers can help promote behavior change and help reinforce a farm culture that supports hearing conservation. The continuation and expansion of hearing screening programs such as these should be encouraged as basic public health strategy in farming communities