Psychometric testing of the Norwegian version of the Nutritional Form For the Elderly among older home-dwelling people

Abstract

BACKGROUND: Nutritional screening instruments need to be evaluated in terms of reliability and validity and being able to demonstrate sensitivity and specificity for use in clinical practice and research. The aims of this study were to test the reliability and validity of the Norwegian version of the Nutritional Form For the Elderly (NUFFE-NO) in a sample of older home-dwelling people, and to use the short form of the Mini Nutritional Assessment (MNA-SF) as a standard. METHODS: A postal questionnaire, including the two instruments, background variables, and health-related questions, was sent to 6033 home-dwelling older people (65+ years) in southern Norway. In total, 2106 persons responded and were included. Data were analyzed statistically regarding homogeneity, concurrent and construct validity, sensitivity, and specificity of NUFFE-NO. RESULTS: A Cronbach's alpha coefficient of 0.71 and significant item-to-total correlations were obtained as measures of homogeneity. Concurrent validity was assessed by a correlation coefficient of -0.37 (P < 0.001) between NUFFE-NO and MNA-SF. NUFFE-NO could separate known nutritional at-risk groups as a measure of construct validity. A cut-off point of ≥4 for identification of older people at nutritional risk was found for NUFFE-NO with MNA-SF as a standard. CONCLUSION: NUFFE-NO shows adequate psychometric properties regarding homogeneity and construct validity. MNA-SF was not found to be the most suitable standard to use, because a low correlation coefficient was obtained as a measure of concurrent validity and a lower cut-off point was found compared with another study using the Mini Nutritional Assessment (MNA(®)) as a standard for NUFFE-NO. The obtained cut-off point of ≥4 is not recommended for use in practice or research, because many false positive nutritional at-risk persons would then be identified. Further studies with suitable design have to be performed among older home-dwelling people using the MNA as a standard.