These significant relevant factors of PDQ-39 were then included in the stepwise multiple linear regression, and the result found that BDI scores (standardized β = 0.520, p = 0.005) were the strongest determinant of QoL in Parkin-related PD, followed by ESS scores (standardized β = 0.346, p = 0.047) (Table 4). The gene discussed is PRKN; the disease is Parkinson disease.