Item Selection for a New Health-Related Quality of Life Measure for Parkinson’s Disease: The Preference-Based Parkinson’s Disease Index (PB-PDI)

Table 2

Impact score of each item on the PB-PDI (n = 53) for those scoring a level 2 or higher.

Item	% scoring a level 2+	Mean (SD) importance rating for level 2+	Mean impact score
Sleep	81.1	4.3 (0.8)	3.5
Fatigue	77.4	4.1 (0.8)	3.2
Tremor	79.2	4.0 (1.1)	3.2
Mood	62.3	4.1 (0.8)	2.6
Walking	56.6	4.3 (0.6)	2.4
Memory	60.4	4.0 (0.9)	2.4
Dexterity	64.2	3.5 (1.1)	2.2
Urine control	52.8	3.9 (0.9)	2.1
Concentration	49.1	3.9 (0.9)	1.9
Speech	35.8	4.3 (0.7)	1.5
Freezing	34.0	4.4 (0.9)	1.5
Swallowing	22.6	4.0 (1.0)	0.9

Impact = (% scoring a level 2+)  (mean importance rating for level 2+)/100. SD, standard deviation.