Stroke Specific Quality of Life Scale: Danish adaptation and a pilot study for testing psychometric properties

Background and purpose: Stroke has an effect on many aspects of quality of life (QoL) and therefore it is important to measure the magnitude of the impact. Items in the American version of the Stroke Specific Quality of Life (SS-QoL) Scale are developed with help from patients with stroke and include even language impairments. Aims: To translate and culturally adapt the American SS-QoL Scale, version 2.0, a stroke-specific instrument measuring health-related QoL, into a Danish version, and to perform a pilot testing of the psychometric properties of the instrument. Methods: The guidelines recommended by Guillemin et al. (J Clin Epidemiol, 46, 1993, 1417) were followed including two independent forward and one back translation, inclusion of laymen, here patients with stroke and their spouses, pretest, and examining selected items with a probing technique. Four couples were included in the pretest, 14 in the pilot study. The patients for pretest and pilot study were selected strategically with regard to interest for participation, experience as stroke survivors, sufficient capacity of language perception and cohabitant status. Results: In the Danish version instructions were made more distinct and formal than in the original American version. Explanatory examples within the items were excluded. One new item adjusted for Danish conditions replaced one in the original version, and the response categories concerning personality were adjusted for cultural differences. The pilot study resulted in a more explicit formulation of the instructions to mark each item only once and on the same line as the item. Conclusions: A Danish version of SS-QoL version 2.0 has been developed and content as well as format has proved relevant and acceptable to patients with stroke including those with impaired language production. The next step is testing the psychometric properties of the instrument.