Development and validation of a short version of the Stroke Specific Quality of Life Scale

Background and purpose The Stroke Specific Quality of Life Scale (SS-QoL) is a well validated measure of health related quality of life in patients with stroke, but with 49 items its length is a disadvantage. A short version of the SS-QoL was developed and tested here. Methods Secondary analyses of three different studies. The short version was developed using data from 141 patients with aneurysmal subarachnoid haemorrhage (SAH) and tested on data from independent samples of 97 patients with SAH and 105 patients with ischaemic stroke or intracerebral haemorrhage. The item with the highest item domain correlation from each of the SS-QoL domains was selected to obtain a 12 item SS-QoL (SS-QoL-12) with a total score and physical and psychosocial subscores. Criterion validity of the SS-QoL-12 scores was tested in each sample with the original SS-QoL as reference. Results All three scores of the SS-QoL-12 showed good internal consistency (Cronbach's alpha 0.77-0.89). The SS-Qol-12 scores predicted 88-95% of the variance of the original SS-QoL. Mean differences between the SS-QoL-12 and SS-QoL and their 95% CI were generally within 0.1 points on a 1-5 scale. The limits of agreement were generally within 0.4 points. Conclusion The SS-QoL-12 has good criterion validity for all subsets of stroke. Because it consists of only 12 questions, this short form will be easy to use in research and clinical settings.