On babies and bathwater: disease impact and negative affectivity in the self-reports of persons with rheumatoid arthritis.

The degree to which self-reports of health and functioning reflect negativity (NA), a dispositional tendency to emphasize the negative, was examined with data from a 7-year longitudinal study of adaptation to rheumatoid arthritis. Principal component analyses performed on each of 8 waves of data consistently indicated that the dominant factor in these data was defined by measures of pain and functional impairment. In the final wave, Disease Impact, a scale derived from this component, was directly compared to NA. The 2 scales demonstrated considerable discriminant validity, and most of the significant intercorrelations among Disease Impact and the other variables examined remained statistically significant after the influence of NA was partialed out. These results suggest that reports of pain, impairment, and associated variables reflected disease-related outcomes and processes and not simply NA.