Depression score (A, C) or quality of life score (B, D) was linearly modeled based on either impairment in ADL (UPDRS-II, measured “off” medication) or neurologist-rated motor impairment (UPDRS-III, measured “on” medication). P-values derived from non-parametric analysis of covariance. All other scales of depression (HAM-D-17, IDS-C, and BDI) were also significantly higher in UF group (see supplemental table 2 for smoothing parameters and p-values for all depression scales).