Validity of self-reported comorbidities in systemic sclerosis.

Objective: To assess the validity of self-reports by patients with systemic sclerosis (SSc) of 5 common, chronic conditions (hypertension, diabetes, cancer, depression, and osteoarthritis/back pain) as compared to chart review.

Methods: SSc patients at a large referral hospital self-reported on a number of comorbidities. Their inpatient and outpatient medical records were abstracted using a standardized data extraction form. Sensitivity, specificity, and positive predictive value of the self-reported diagnoses were calculated using data from the chart review as gold standard.

Results: Self-reported comorbidity data were verified by chart review for 130 patients with SSc. The sensitivity of the self-reports for the 5 comorbid conditions was low [range 35% (cancer) to 86% (diabetes)]. The specificity was moderate to high [range 76% (osteoarthritis/back pain) to 99% (cancer)]. The positive predictive values ranged from 31% (depression) to 86% (cancer).

Conclusion: Self-reports of comorbidities do not provide optimal data for the identification of common, chronic conditions in patients with SSc.