Content validation of two SF-36 subscales for use in type 2 diabetes and non-dialysis chronic kidney disease-related anemia

UMMS Affiliation

Department of Quantitative Health Sciences

Publication Date


Document Type



Health Surveys; Health Status; Questionnaires; Activities of Daily Living; Quality of Life; Sickness Impact Profile; Diabetes Mellitus, Type 2


Biostatistics | Epidemiology | Health Services Research


PURPOSE: This study aimed to evaluate the relevance and importance of two SF-36 subscales, Vitality (VT) and Physical Function (PF), to assess concepts of energy and physical function in patients with type 2 diabetes mellitus (DM) and non-dialysis CKD-related anemia.

METHODS: Patients with clinical history of DM and non-dialysis CKD-related anemia (n = 68) were identified as follows: 40 participated in concept elicitation (CE) interviews; 20 in cognitive interviews (CI), and 8 in pilot interviews. Relevance and importance ratings for SF-36 VT and PF items were obtained. Interviews were recorded, transcribed, and patient expressions of concepts coded. Inter-rater agreement was used to evaluate coding consistency. Concepts elicited were mapped to SF-36 VT and PF items.

RESULTS: Patients (n = 64) were 65.6% women, 42.2% Caucasian, with mean age of 66.1 +/- 11.6 years. Of 830 coded concepts, 388 (47%) were "Energy" expressions and 287 (35%) were "PF limitations" expressions. Low energy was reported by 85% patients and rated as an important limitation by 88%. Limitations in PF were reported by 56-82% patients and rated important by 44-96%. CE and CI quotes correspond well to SF-36 VT and PF items.

CONCLUSION: SF-36 VT and PF contents were suitable for assessing energy and physical function limitations, respectively, in this patient population.

DOI of Published Version



Qual Life Res. 2010 Dec 16. Link to article on publisher's site

Journal/Book/Conference Title

Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation

PubMed ID


Related Resources

Link to Article in PubMed