The sense of coherence scale in patients with rheumatoid arthritis

Abstract
Objective. To analyze Antonovsky's Sense of Coherence (SOC) Scale, in 828 patients with rheumatoid arthritis (RA) from 15 private rheumatology practices. This scale is designed to evaluate strengths within individuals that allow them to select appropriate strategies to deal with stressors; both the total 29-item (SOC-29) total scale and a 13-item (SOC-13) short form of the 29-item scale were analyzed. Methods. Data were collected through mailed self-report questionnaires as a component of a long-term monitoring program. Internal consistency was evaluated according to Cronbach's alpha. Split-halves reliability was estimated according to the Spearman-Brown prophecy formula. Associations of the SOC-29 and the SOC-13 scale scores with demographic, clinical, and psychological variables were analyzed according to Pearson product moment correlations. Results. Lower SOC-29 and SOC-13 scale scores were correlated significantly with higher scores for difficulty in performing activities of daily living (ADL), a visual analog pain scale score, global health status, and perceived learned helplessness. The levels of correlation for these variables suggest that each measure represents a construct that differs from the SOC. Lower scale scores were also correlated significantly with fewer years of formal education, adjusted for age, sex, and disease duration. Conclusions. The SOC-29 and SOC-13 scales are reliable and valid in patients with RA. The SOC scale explained in part variation in clinical status in patients with RA. The SOC-13 provides utility comparable to the SOC-29 in patients with RA.