2005) and the validity of the single item on work ability has been demonstrated

(Ahlstrom et al. 2010). Changed work ability was measured as the difference between the buy FK228 estimated values at different times. Working degree ranged from 0 to 100%, in steps of 25%, of participants’ registered or self-rated working time. Pain was measured by the instrument developed by Von Korff et al. (Von Korff et al. 1992), a numeric pain scale (0–10) ranging from “no pain” to “worst pain”. We used it for the body areas neck and arms/hands/fingers. For each area, one question about average pain over the previous month was included. Decreased pain was measured as the difference in points between times of measurement.

Self-rated mental health (five items) and vitality (four items) were measured by the Copenhagen Psychosocial Questionnaire (Kristensen et al. 2005). Each 5- and 6-graded response scale was recalculated to an index of 0–100 points. Laboratory-observed tests Cutlery check details wiping performance test was developed to reflect a standardized domestic work task, which all participants could be familiar with, but none had the task included in their normally assignments at work. It measures the number of wiped pieces of cutlery per minute. The test was performed in standing position next to a 90-cm-high bench top. The cutlery was soaked in water and placed in a washing-up bowl; cutlery was wiped one piece at a time and placed in a dry bowl. Participants were instructed to

wipe 60 pieces of cutlery at their own pace. The test was developed, piloted, and reliability tested for the purposes of this study (Ahlstrand et al. 2009). A test–retest was performed with twelve female workers. The data were analyzed with Bland and Altman’s (1999) limits of agreement (-)-p-Bromotetramisole Oxalate test (Bland and Altman 1999). This test gives an indication of individuals own work ability while doing a domestic work task with the upper extremities. Dexterity/Gross movements of hands, fingers, and arms, and fingertip dexterity were measured using a Purdue Pegboard®. The test is to place as many pegs as possible in a vertical row (rows) within 30 s, with their dominant hand. The maximal grip strength (kp) in the hand was measured by Jamar 5030J1 Hydraulic Hand Dynamometer®, right hand, average of three times. Muscle activity bipolar surface electromyography (sEMG) was collected bilaterally from the descending part of the upper trapezius muscle by means of disposable Ag–AgCl electrodes (Type: N-00-S, Medicotest A/S, Olstykke, Denmark) placed along the direction of the muscle fibers with a center-to-center distance of 2 cm. The electrodes were centered 2 cm lateral to the midpoint of the line connecting vertebra C7 and the acromion. The myoelectric signal was recorded with a laptop-based system (Karlsson et al.