A brief description of the initially reported psychometric properties of the measure.
Findings showed that this measure is reliable, it has face validity and is a well-accepted measure (Kriston et al, 2010). A comparison of the SDM-Q-9 and the original OPTION scale (scored by expert observers), strengthened the psychometric standing of the measure, as while the OPTION scale had limited internal consistency and the inter-rater reliability was low, the SDM-Q-9 demonstrated good internal consistency (Scholl, Kriston, Dirmaier & Harter, 2015). Generalizability of these findings is limited however, as it has only been tested within Germany and on a particular sample (the elderly). Therefore, while this measure looks promising, further testing of criterion validity and of its performance in other populations is necessary.