Establishing clinically meaningful within-individual improvement thresholds for eight patient-reported outcome measures in people with relapsing-remitting multiple sclerosis

Journal of Patient-Reported Outcomes

Table 5 Within-individual change estimates from distribution-based methods for TSQM v1.4, HADS, PDDS and HRPQ-MS v2 scores

Score	SD_BL	0.5 SD_BL	SEM^a	Min detectable change	Recommended value^b
Multi-item scores
TSQM v1.4
Side effects	28.64	14.32	6.83	18.94	14.32
Effectiveness	19.98	9.99	5.73	15.89	9.99
Convenience	21.62	10.81	5.59	15.48	10.81
Global satisfaction	24.49	12.24	7.72	21.41	12.24
HADS
Anxiety	4.35	2.18	1.59	4.39	2.18
Depression	4.02	2.01	1.58	4.39	2.01
Single-item scores
PDDS
–	1.98	0.99	–	–	0.99
HRPQ-MS v2
Lost work absenteeism household	3.77	1.88	–	–	1.88
Lost work absenteeism workplace	5.35	2.67	–	–	2.67
Lost work presenteeism household	4.07	2.03	–	–	2.03
Lost work presenteeism workplace	5.03	2.51	–	–	2.51
Lost work total household	6.45	3.22	–	–	3.22
Lost work total workplace	7.90	3.95	–	–	3.95
Percent lost work absenteeism household	29.40	14.70	–	–	14.70
Percent lost work absenteeism workplace	16.54	8.27	–	–	8.27
Percent lost work presenteeism household	22.73	11.36	–	–	11.36
Percent lost work presenteeism workplace	14.68	7.34	–	–	7.34
Percent lost work total household	38.33	19.17	–	–	19.17
Percent lost work total workplace	23.13	11.57	–	–	11.57
Work presenteeism household	8.51	4.26	–	–	4.26
Work presenteeism workplace	13.83	6.92	–	–	6.92

^aSEM based on Cronbach’s alpha calculated at baseline. ^bThe recommended value for meaningful within-individual change was defined by 0.5SD at baseline
HADS Hospital Anxiety and Depression Scale; HRPQ-MS v2 Health-Related Productivity Questionnaire in Multiple Sclerosis version 2; PDDS Patient-Determined Disease Steps; SD_BL Standard deviation at baseline; SEM Standard error of measurement; TSQM v1.4 Treatment Satisfaction Questionnaire with Medication version 1.4