The Sequential Occupational Dexterity Assessment (SODA) is a reliable and valid instrument to measure bimanual hand function in rheumatoid arthritis. Since administering SODA is time-consuming, the aim of this study is to construct a short SODA (SODA-S).
Dexterity was measured with the SODA twice (with an interval of one year) in 94 patients. Item analyses based on the different SODA tasks were carried out to determine which of the 12 individual tasks were most responsible for the observed changes in dexterity.
Six of the 12 SODA tasks were identified as sensitive to change. Based on these 6 tasks, the SODA-S was computed. Internal consistency of the SODA-S is good (Cronbach's alphas at baseline and followup were 0.82 and 0.85, respectively). The correlation between the SODA and SODA-S is 0.92. This means that the information gathered from the SODA-S is almost equal to the information gathered from the full SODA. Norm scores are provided for both instruments.
The SODA-S is a good alternative to the full SODA in following patient's dexterity in daily practice. However, when evaluating the effect of specific hand treatment, the full SODA may be preferred.