BackgroundFamilies’ perspectives are of great importance in evaluating quality of care in the intensive care unit (ICU). This Danish-Dutch study tested a European adaptation of the “Family Satisfaction in the ICU” (euroFS-ICU). The aim of the study was to examine assessments of satisfaction with care in a large cohort of Danish and Dutch family members and to examine the measurement characteristics of the euroFS-ICU.MethodsData were from 11 Danish and 10 Dutch ICUs and included family members of patients admitted to the ICU for 48 hours or more. Surveys were mailed 3 weeks after patient discharge from the ICU. Selected patient characteristics were retrieved from hospital records.ResultsA total of 1077 family members of 920 ICU patients participated. The response rate among family members who were approached was 72%. “Excellent” or “Very good” ratings on all items ranged from 58% to 96%. Items with the highest ratings were concern toward patients, ICU atmosphere, opportunities to be present at the bedside, and ease of getting information. Items with room for improvement were management of patient agitation, emotional support of the family, consistency of information, and inclusion in and support during decision-making processes. Exploratory factor analysis suggested four underlying factors, but confirmatory factor analysis failed to yield a multi-factor model with between-country measurement invariance. A hypothesis that this failure was due to misspecification of causal indicators as reflective indicators was supported by analysis of a factor representing satisfaction with communication, measured with a combination of causal and reflective indicators.ConclusionsMost family members were moderately or very satisfied with patient care, family care, information and decision-making, but areas with room for improvement were also identified. Psychometric assessments suggest that composite scores constructed from these items as representations of either overall satisfaction or satisfaction with specific sub-domains do not meet rigorous measurement standards. The euroFS-ICU and other similar instruments may benefit from adding reflective indicators.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-017-1826-7) contains supplementary material, which is available to authorized users.