Subjective assessment of nutritional status-validity and reliability of a modified Detsky index in a Swedish setting

In the search for a clinically useful nutritional index for use in a European context, we have translated an American nutritional assessment index - Subjective Global Assessment (SGA), and tested the modified translated version for validity and reliability in a Swedish setting. Judgements by an expert panel resulted in a mean agreement of 71% for clarity, 80% for content validity and 65% for internal consistency. Construct validity was demonstrated by the use of contrasting patient-groups (n = 20) and by 90% agreement with a medical expert as 'gold standard' for unknown patients (n = 20). Inter-rater reliability showed 75% agreement by 3 Registered Nurses (RNs) (n = 20). The individual Kappas for the raters varied from 0.68 to 0.89. The study showed difficulties experienced by raters in relating certain aspects in the SGA-index to normality. However, we concluded that a modified SGA-index translated from one language to another, with all the problems of cultural and idiomatic differences, can be of value for assessing and documenting pre-operative nutritional status of patients undergoing gastrointestinal surgery in a Swedish setting.