Scoring Mental Health Quality of Life With the SF-36 in Patients With and Without Diabetes Foot Complications

The aim of this study was to examine if using orthogonal and oblique factor analysis detect changes in health-related quality of life differently in diabetic patients on the Short Form-36 (SF-36) survey. A total of 155 patients had diabetic foot complications (DFC), and 145 patients had no DFCs. The SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores were calculated using scoring coefficients determined by orthogonal and oblique rotation principle component analyses of the subscales. The DFC group had lower orthogonal ( P < .00001) and oblique PCS scores ( P < .00001). However, despite lower Mental Health subscale scores in the patients with DFCs, orthogonal MCS scores ( P = .156) did not differ. In contrast, the oblique MCS scores reflected the difference in the Mental Health subscale ( P = .0005). Orthogonal and oblique PCS scores did not differ significantly. However, orthogonal MCS scores were significantly higher than oblique MCS scores in those with DFCs ( P = .0004) and without DFCs ( P = .005). The shorter, 12-item SF-12 survey demonstrated similar results. Poorer physical function leads to higher orthogonal MCS scores than if determined by oblique scoring coefficients since Physical Function, Bodily Pain, and General Health are weighted more negatively in orthogonal coefficients when calculating the MCS score. Oblique scoring coefficients may address this issue, but further study is necessary to confirm whether oblique MCS scores accurately represent the mental health of patients with diabetic foot disease.

The PROMIS Global Health Questionnaire Correlates With the QuickDASH in Patients With Upper Extremity Illness

Background: The objective of this study is to evaluate the construct validity of the Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health instrument by establishing its correlation to the Quick-Disabilities of the Arm, Shoulder and Hand (QuickDASH) questionnaire in patients with upper extremity illness. Methods: A cohort of 112 patients completed a sociodemographic survey and the PROMIS Global Health and QuickDASH questionnaires. Pearson correlation coefficients were used to evaluate the association of the QuickDASH with the PROMIS Global Health items and subscales. Results: Six of the 10 PROMIS Global Health items were associated with the QuickDASH. The PROMIS Global Physical Health subscale showed moderate correlation with QuickDASH and the Mental Health subscale. There was no significant relationship between the PROMIS Global Mental Health subscale and QuickDASH. Conclusions: The consistent finding that general patient-reported outcomes correlate moderately with regional patient-reported outcomes suggests that a small number of relatively nonspecific patient-reported outcome measures might be used to assess a variety of illnesses. In our opinion, the blending of physical and mental health questions in the PROMIS Global Health makes this instrument less useful for research or patient care.