To evaluate the reliability, validity, responsiveness, and utility of the Lupus Impact Tracker (LIT).
This was a prospective longitudinal study with 20 North American sites participating. Consenting patients completed the LIT, Medical Outcomes Study Short Form 36 (version 2), Patient Health Questionnaire 9 (PHQ-9), LupusQoL, and patient LIT feedback questionnaire. Rheumatologists completed the Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA) version of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index, and physician LIT feedback questionnaire. The reliability, convergent validity, construct validity, and responsiveness of the LIT were evaluated.
Of the 325 SLE patients enrolled, 90% were female, 53% were white, and 33% were African American. Their mean age was 42 years. The mean ± SD baseline physician's global assessment and total SELENA-SLEDAI scores were 1.04 ± 0.8 and 4.28 ± 3.8, respectively, while 3-month scores were 0.94 ± 0.73 and 4.09 ± 3.79, respectively. Internal consistency reliability was high (>0.9) at both visits. LIT scores correlated highly with other measures of patient-reported outcomes, and construct validity was established against clinical measures. The LIT was highly responsive to patient-reported changes in SLE health status; however, LIT scores were not as responsive to changes in the SELENA-SLEDAI score. The majority of patients and physicians found LIT to be acceptable and feasible to administer in a clinical setting.
The LIT is a reliable and valid instrument for assessing the impact of SLE on patients and captures unique and important information not included in physician assessments of disease. It may be useful in clinical practice to facilitate communication between the physician and the patient and enable efficient incorporation of the patient's perspective in disease management.