Assessing the stroke-specific quality of life for outcome measurement in stroke rehabilitation: minimal detectable change and clinically important difference.
BACKGROUND
This study was conducted to establish the minimal detectable change (MDC) and clinically important differences (CIDs) of the physical category of the Stroke-Specific Quality of Life Scale in patients with stroke.


METHODS
MDC and CIDs scores were calculated from the data of 74 participants enrolled in randomized controlled trials investigating the effects of two rehabilitation programs in patients with stroke. These participants received treatments for 3 weeks and underwent clinical assessment before and after treatment. To obtain test-retest reliability for calculating MDC, another 25 patients with chronic stroke were recruited. The MDC was calculated from the standard error of measurement (SEM) to indicate a real change with 95% confidence for individual patients (MDC95). Distribution-based and anchor-based methods were adopted to triangulate the ranges of minimal CIDs. The percentage of scale width was calculated by dividing the MDC and CIDs by the total score range of each physical category. The percentage of patients exceeding MDC95 and minimal CIDs was also reported.


RESULTS
The MDC95 of the mobility, self-care, and upper extremity (UE) function subscales were 5.9, 4.0, and 5.3 respectively. The minimal CID ranges for these 3 subscales were 1.5 to 2.4, 1.2 to 1.9, and 1.2 to 1.8. The percentage of patients exceeding MDC95 and minimal CIDs of the mobility, self-care, and UE function subscales were 9.5% to 28.4%, 6.8% to 28.4%, and 12.2% to 33.8%, respectively.


CONCLUSIONS
The change score of an individual patient has to reach 5.9, 4.0, and 5.3 on the 3 subscales to indicate a true change. The mean change scores of a group of patients with stroke on these subscales should reach the lower bound of CID ranges of 1.5 (6.3% scale width), 1.2 (6.0% scale width), and 1.2 (6.0% scale width) to be regarded as clinically important change. This information may facilitate interpretations of patient-reported outcomes after stroke rehabilitation. Future research is warranted to validate these findings.
Department of Occupational Therapy, College of Medicine, National Taiwan University, and Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan.
Keh-chung
KC
Lin
Tiffany
T
Fu
Ching-yi
CY
Wu
Ching-ju
CJ
Hsieh
D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D051346:Mobility Limitation; D009483:Neuropsychological Tests; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011788:Quality of Life; D020127:Recovery of Function; D020521:Stroke / Q000503:physiopathology / Q000523:psychology; D000071939:Stroke Rehabilitation; D011795:Surveys and Questionnaires; D034941:Upper Extremity / Q000503:physiopathology*
Arch Phys Med Rehabil. 2003 Jul;84(7):950-63
12881816
Neuroepidemiology. 2008;31(1):57-66
18560244
Phys Ther. 1987 Feb;67(2):206-7
3809245
J Clin Epidemiol. 2006 Oct;59(10):1033-9
16980142
Phys Ther. 2007 Feb;87(2):170-8
17244694
Neurorehabil Neural Repair. 2009 Jun;23(5):441-8
19118130
Neurorehabil Neural Repair. 2008 Nov-Dec;22(6):723-7
18776067
J Clin Epidemiol. 1997 Aug;50(8):869-79
9291871
Med Care. 1999 May;37(5):469-78
10335749
Stroke. 1999 Oct;30(10):2131-40
10512918
Health Qual Life Outcomes. 2010 Oct 11;8:117
20937112
Qual Life Res. 2002 May;11(3):207-21
12074259
J Clin Epidemiol. 2008 Feb;61(2):102-9
18177782
Neurol Sci. 2006 Apr;27(1):40-6
16688598
Lancet Neurol. 2007 Apr;6(4):362-72
17362840
Neurorehabil Neural Repair. 2010 Jun;24(5):486-92
20053950
J Psychiatr Res. 1975 Nov;12(3):189-98
1202204
J Clin Epidemiol. 1999 Sep;52(9):861-73
10529027
Eur Respir J. 1999 Jul;14(1):23-7
10489824
Neurosurgery. 2010 Apr;66(4):772-83
20190663
Health Technol Assess. 2004 Mar;8(9):iii, 1-48
14982653
Neurorehabil Neural Repair. 2007 Mar-Apr;21(2):137-51
17312089
Orthop Nurs. 2005 Jan-Feb;24(1):14-24
15722968
BMC Neurol. 2008 Apr 11;8:7
18405377
Phys Ther. 2002 Jan;82(1):8-24
11784274
Mayo Clin Proc. 2002 Apr;77(4):384-92
11936936
Clin Rehabil. 2007 Jul;21(7):620-7
17702704
J Rehabil Med. 2008 Nov;40(10):836-43
19242621
Neurorehabil Neural Repair. 2011 Feb;25(2):130-9
20947493
Stroke. 1999 Jul;30(7):1362-9
10390308
Scand J Caring Sci. 2010 Jun;24(2):211-8
20230517
Stroke. 2009 Aug;40(8):2805-11
19556535
Stroke. 2006 Aug;37(8):2081-5
16809575
Qual Life Res. 2009 Aug;18(6):765-73
19459067
Cerebrovasc Dis. 2009;27 Suppl 1:204-14
19342853
Arch Phys Med Rehabil. 2008 Sep;89(9):1693-700
18760153
COPD. 2005 Mar;2(1):157-65
17136977
CMAJ. 2004 Aug 17;171(4):353-8
15313996
Soc Sci Med. 2007 Feb;64(3):735-46
17079060
Arch Phys Med Rehabil. 1997 Jul;78(7):725-9
9228875
Stroke. 2006 Aug;37(8):1958-9
16809553
J Clin Epidemiol. 2006 Jan;59(1):45-52
16360560
Mayo Clin Proc. 2002 Apr;77(4):371-83
11936935
Qual Life Res. 2002 Feb;11(1):1-7
12003051
J Neurol Neurosurg Psychiatry. 2010 May;81(5):485-9
19828480
J Clin Epidemiol. 2003 May;56(5):395-407
12812812
Phys Ther. 2003 Oct;83(10):888-98
14519060
J Sleep Res. 2003 Dec;12(4):291-8
14633240
Stroke. 1995 Jun;26(6):982-9
7762050
Int J Rehabil Res. 2008 Jun;31(2):111-7
18467925
Cancer. 2007 Jul 1;110(1):196-202
17546575
Osteoarthritis Cartilage. 2007 Aug;15(8):918-31
17383907
Med Care. 2003 May;41(5):582-92
12719681
J Clin Epidemiol. 2004 Oct;57(10):1008-18
15528051
Health Qual Life Outcomes. 2010 Mar 30;8:35
20353582
Neurorehabil Neural Repair. 2007 Mar-Apr;21(2):161-8
17312091
J Altern Complement Med. 2009 Oct;15(10):1067-1073
20050300
J Cardiopulm Rehabil. 2005 Nov-Dec;25(6):370-7
16327533
Stroke. 2009 Apr;40(4):1526-9
19095984
Phys Ther. 2006 Jul;86(7):944-54
16813475
Eur Spine J. 2003 Feb;12(1):12-20
12592542