Clinical Study Clinically important difference of Stroke-Specific Quality of Life Scale for aneurysmal subarachnoid hemorrhage George K.C. Wong a,⇑ , Alex Lee a , Adrian Wong b , Faith L.H. Ho a , Sandy L.Y. Leung a , Benny C.Y. Zee c , Wai S. Poon a , Deyond Y.W. Siu d , Jill M. Abrigo e , Vincent C.T. Mok b a Division of Neurosurgery, Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, 30 Ngan Shing St, Sha Tin, New Territories, Hong Kong b Division of Neurology, Prince of Wales Hospital, The Chinese University of Hong Kong, Sha Tin, New Territories, Hong Kong c School of Public Health and Primary Care, Prince of Wales Hospital, The Chinese University of Hong Kong, Sha Tin, New Territories, Hong Kong d Department of Diagnostic Radiology, Kwong Wah Hospital, Hong Kong e Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong article info Article history: Received 21 April 2016 Accepted 5 May 2016 Available online xxxx Keywords: Quality of life Stroke Subarachnoid hemorrhage abstract Health-related quality of life measurements, are commonly used to quantify burden of disease, to evaluate treatment method, and to facilitate benchmarking. The aim of the current study was to deter- mine the Clinically Important Difference (CID) for a Chinese version of Stroke-specific Quality of Life (SS-QOL) in an aneurysmal subarachnoid hemorrhage (SAH) patient cohort. The study recruited SAH patients in a neurosurgical unit in Hong Kong. SAH patients who completed both 3-month and 1-year assessments were included in the analysis. The study received ethical approvals from the joint CUHK-NTEC Clinical Ethics Committee and written informed consent was obtained from all participants or their next of kins. Over a 2-year period, 65 eligible patients were included in the study. Employing the anchor-based approach with global rating of change, the CID estimate of SS-QOL total score was 4.7 (95% confidence interval [CI]: 2.5–5.3), the CID estimate for SSQOL physical subscore was 2.1 (95% CI: 0.3–2.4), and the CID estimate for SS-QOL psychosocial subscore change was 2.8 (95% CI: 1.8–3.7). In conclusion, our study defined the CID for SS-QOL applied to SAH patients and should be further validated in another SAH patient population. Ó 2016 Elsevier Ltd. All rights reserved. 1. Introduction Subarachnoid hemorrhage (SAH) from a ruptured intracranial aneurysm accounts for approximately 5% of all strokes, occurs at a relatively young age, and carries a worse prognosis, despite improvement in medical care with time [1–3]. Moreover, quality of life is often decreased in SAH survivors, as confirmed in reported case series and our Asia–Pacific cohorts [4,5]. Health-related qual- ity of life is perceived as a better measure of outcome, especially in SAH patients [6–8]. Health-related quality of life measurements, are commonly used to quantify burden of disease, to evaluate treatment method, and to facilitate benchmarking. For outcome research, a combination of generic (allows comparisons across dif- ferent disease populations) and disease-specific (sensitive to disease-specific problems) measures is recommended [9]. Stroke-specific Quality of Life Scale (SS-QOL) is one of the com- monest disease-specific quality of life measures initially developed and validated for ischemic stroke patients in 1999 [10], and subse- quently, in mixed ischemic and hemorrhagic stroke patients in 2007 [11]. For SAH, Dutch version SS-QOL was first validated in 2010 using a Dutch version [3]. Our group had subsequently vali- dated the Chinese Version of SS-QOL in a local SAH population [12]. Our analysis suggested a different dichotomization of physi- cal (upper extremity, vision, work productivity, energy, family roles, mobility, self-care) and psychosocial (personality, thinking, mood, language, social role) subscores, which may reflect cultural differences. Moreover, cognitive impairment and psychiatric dys- function are common in local and international studies [13–18]. A clinically important change refers to a difference that is consid- ered meaningful and worthwhile by the patient such that he or she would choose to receive the same treatment again [19]. Statis- tically significant difference might theoretically be too small to have practical implication to benchmark for more effective treat- ment [20]. The clinically important difference (CID) of an instru- ment such as SS-QOL for SAH is important to understand, so as to give meaningful interpretation of assessment results and inter- pret clinical trials. Before the application of SS-QOL to evaluate http://dx.doi.org/10.1016/j.jocn.2016.05.029 0967-5868/Ó 2016 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +852 2632 2624; fax: +852 2637 7974. E-mail address: georgewong@surgery.cuhk.edu.hk (G.K.C. Wong). Journal of Clinical Neuroscience xxx (2016) xxx–xxx Contents lists available at ScienceDirect Journal of Clinical Neuroscience journal homepage: www.elsevier.com/locate/jocn Please cite this article in press as: Wong GKC et al. Clinically important difference of Stroke-Specific Quality of Life Scale for aneurysmal subarachnoid hemorrhage. J Clin Neurosci (2016), http://dx.doi.org/10.1016/j.jocn.2016.05.029