Purpose: To investigate whether patient-spouse co-reporting (patient reporting with assistance from their spouse) results in the same ratings of health-related quality of life (HRQoL) as patient ratings without co-reporting, and to assess whether mutuality of the marital relationship is a determinant of co-reported ratings. Patients are the best source of HRQoL; however, co-reporting is common in clinical settings, but has not been compared to independent patient reporting of HRQoL.
Methods: Fifty-nine Parkinson's disease (PD) patient-spouse pairs completed the Short Form Health Status Survey (SF-12), measuring mental and physical HRQoL. Initially, the patient and spouse completed the SF-12 independently (about the patient). Then, patient-spouse pairs completed the SF-12 together assessing the patient's HRQoL. Patients and spouses independently completed the Mutuality Scale rating the intimacy of their relationship.
Results: Patients rated physical HRQoL higher (M = 46.6) than spouses alone (M = 43.4, p < 0.01) and co-reporting (M = 44.8, p < 0.05). Co-reporting rated physical HRQoL in between that of patients and spouses, (p < 0.05). Spouses who reported greater mutuality showed greater concordance with the patient regarding the patient's mental HRQoL (B = -0.43, p < 0.05).
Conclusion: Consistency of the mode of completion of HRQoL instruments is important since co-reporting may alter HRQoL ratings in PD and lead to inaccurate conclusions. Mutuality is a mediator of mental HRQoL.