Social support, disability and depression: a longitudinal study of rheumatoid arthritis.

The objectives of this study were (i) to assess aspects of the reliability and validity of an instrument measuring social support and social relationships, in the field of physical disability; (ii) to assess the impact of disability on social relationships and (iii) to examine effects of social support upon psychological well-being over time. One hundred and forty nine individuals with rheumatoid arthritis (RA) were assessed on two occasions separated by 15 months. Social support was assessed by means of the Interview Schedule for Social Interaction. The instrument was found to have satisfactory reliability and validity. It revealed that more diffuse social relationships were more affected by RA. Scores for social relationships were as strongly related to depressed mood over time as were disease and disability variables.