This study examined the accuracy of depression cross-walk tables in a sample of people with multiple sclerosis (MS). The tables link scores of two commonly used depression measures to the Patient Reported Outcome Measurement Information System Depression (PROMIS-D) scale metric. We administered the 8-item PROMIS-D (Short-Form 8b; PROMIS-D-8), the 20-item Center for Epidemiologic Studies Depression Scale (CESD-20), and the 9-item Patient Health Questionnaire (PHQ-9) to 459 survey participants with MS. We examined correlations between actual PROMIS-D-8 scores and the scores predicted by cross-walks based on PHQ-9 and CESD-20 scores. Intraclass correlation coefficients were used to assess correspondence. Consistency in severity classification was also calculated. Finally, we used Bland-Altman plots to graphically examine the levels of agreement. The correlations between actual and cross-walked PROMIS-D-8 scores were strong (CESD-20 = .82; PHQ-9 = .74). The intraclass correlation was moderate (.77). Participants were consistently classified as having or not having at least moderate depressive symptoms by both actual and cross-walked scores derived from the CESD-20 (90%) and PHQ-9 (85%). Bland-Altman plots suggested the smaller differences between actual and cross-walked scores with greater-than-average depression severity. PROMIS cross-walk tables can be used to translate depression scores of people with MS to the PROMIS-D metric, promoting continuity with previous research.
Keywords: CESD; Center for Epidemiologic Studies Depression Scale; PHQ-9; PROMIS; Patient Health Questionnaire-9; Patient Reported Outcome Measurement Information System; cross-walking; depression; linking; multiple sclerosis.