Investigation of the performance of an ergonomic handrim as a pain-relieving intervention for manual wheelchair users.

Manual wheelchair users commonly experience pain in their hands and wrists associated with the repetitive stress of propulsion. The objective of this research was to examine the effect of an ergonomic wheelchair handrim as an intervention designed to reduce pain in the hands and wrists and improve functional outcomes for manual wheelchair users. Three studies were conducted to achieve this objective. In the first study, 10 individuals with paraplegia underwent a biomechanical analysis before and after a 2-week practice period with a Natural-Fit (NF) prototype ergonomic handrim. The biomechanical results showed that grip moments were reduced with the NF handrim prototype as compared with the subjects' current handrim (p < .1). Other biomechanical findings were mixed. In the second study, 46 manual wheelchair users who replaced their standard handrim with the commercially available NF handrim completed a questionnaire of retrospective measures of symptom severity. Average duration of use of the NF was 6 months. When asked to compare propelling with the NF to propelling with their prior handrims, 85% of respondents reported less pain in their hands and 80% reported less pain in their wrists. The third study was a replication and extension of Study 2: 82 manual wheelchair users who replaced their standard handrim with the NF completed retrospective symptom severity and functional status scales after using the NF for an average of 9 months. Results again confirmed that using the NF led to a reduction in the severity of symptoms and to improved functional outcomes.

Attitude importance and the accumulation of attitude-relevant knowledge in memory.

People who attach personal importance to an attitude are especially knowledgeable about the attitude object. This article tests an explanation for this relation: that importance causes the accumulation of knowledge by inspiring selective exposure to and selective elaboration of relevant information. Nine studies showed that (a) after watching televised debates between presidential candidates, viewers were better able to remember the statements made on policy issues on which they had more personally important attitudes; (b) importance motivated selective exposure and selective elaboration: Greater personal importance was associated with better memory for relevant information encountered under controlled laboratory conditions, and manipulations eliminating opportunities for selective exposure and selective elaboration eliminated the importance-memory accuracy relation; and (c) people do not use perceptions of their knowledge volume to infer how important an attitude is to them, but importance does cause knowledge accumulation.