This study is designed to examine how differences in modes of data capture affect psychometric properties and score differences and to evaluate the consistency of these results across three PROMIS health domains: emotional distress-depression, fatigue, and physical function. Four modes of administration will be compared: interactive voice response (IVR) technology, paper and pencil questionnaire, personal computer, and personal digital assistant (PDA). A total of 800 patients will be enrolled from three diagnostic groups: chronic obstructive pulmonary disease (COPD), depression, and rheumatoid arthritis. The study will test for equivalence across modes of administration, with the hypothesis that there are no mode effects; if mode effects are found, their magnitude across modes will be estimated. This network project will result in an improved understanding of the effect of assessment mode on patient-reported outcome (PRO) data. Guidance from this project can help in planning future PROMIS activities beyond the present PROMIS program.