Shared decision-making for patients with psychotic disorders: validating the measure "collaboRATE for Next of Kin...

Family involvement and shared decision-making (SDM) are key elements in current mental health treatment. While it is important to measure the level of SDM from the perspective of relatives, suitable validated measures are lacking. Moreover, supported decision-making has gradually been emphasized more than substituted decision-making. In a large-scale implementation study of family involvement in the treatment of psychosis, we explored SDM for patients' closest relatives. We present the first validation of a three-item instrument to evaluate SDM for relatives acting to support patient autonomy, building on existing collaboRATE measures.

For the new collaboRATE measure for relatives, we assessed scale reliability and concurrent and discriminant validity using available data from our implementation study. The study included relatives of patients treated for psychosis at community mental health centers, with data acquired and analyzed at baseline (n = 198 relatives) and 6-month follow-up (n = 173).

The new collaboRATE measure for relatives had excellent scale reliability, with Cronbach's alpha values ranging from 0.91 to 0.95. Scores on the collaboRATE for relatives were correlated with the scores on matching items from the Carer Well-Being and Support questionnaire, with Pearson r values varying from r = 0.49 to r = 0.66, supporting concurrent validity. Exploratory analysis provided further tentative support for concurrent validity, indicating significantly lower collaboRATE scores for relatives of patients in compulsory care compared to voluntary care. We observed small negative correlations between the collaboRATE scores and the relatives' responses to subscales of the Experience of Caregiving Inventory, which only partly supported discriminant validity.

These validation data provide initial support for the new collaboRATE measure to assess SDM from the perspective of relatives supporting patient autonomy, although further validations are needed.