Psychometric evaluation of the SF-36 (v.2) questionnaire in a probability sample of Brazilian households: results of the survey Pesquisa Dimensões Sociais das Desigualdades (PDSD), Brazil, 2008

Abstract

BackgroundIn Brazil, despite the growing use of SF-36 in different research environments, most of the psychometric evaluation of the translated questionnaire was from studies with samples of patients. The purpose of this paper is to examine if the Brazilian version of SF-36 satisfies scaling assumptions, reliability and validity required for valid interpretation of the SF-36 summated ratings scales in the general population.Methods12,423 individuals and their spouses living in 8,048 households were selected from a stratified sample of all permanent households along the country to be interviewed using the Brazilian SF-36 (version 2). Psychometric tests were performed to evaluate the scaling assumptions based on IQOLA methodology.ResultsData quality was satisfactory with questionnaire completion rate of 100%. The ordering of the item means within scales clustered as hypothesized. All item-scale correlations exceeded the suggested criteria for reliability with success rate of 100% and low floor and ceiling effects. All scales reached the criteria for group comparison and factor analysis identified two principal components that jointly accounted for 67.5% of the total variance. Role emotional and vitality were strongly correlated with physical and mental components, respectively, while social functioning was moderately correlated with both components. Role physical and mental health scales were, respectively, the most valid measures of the physical and mental health component. In the comparisons between groups that differed by the presence or absence of depression, subjects who reported having the disease had lower mean scores in all scales and mental health scale discriminated best between the two groups. Among those healthy and with one, two or three and more chronic illness, the average scores were inverted related to the number of diseases. Body pain, general health and vitality were the most discriminating scales between healthy and diseased groups. Higher scores were associated with individuals of male sex, age below 40 years old and high schooling.ConclusionsThe Brazilian version of SF-36 performed well and the findings suggested that it is a reliable and valid measure of health related quality of life among the general population as well as a promising measure for research on health inequalities in Brazil.

Health-related Quality of Life in Metastatic and Adjuvant Breast Cancer Patients

“…The latter are often used to assess cancer therapies and investigate patients with chronic disease [21]. The validity of the indicator has been confirmed in different studies in which patients with chronic disease rated their quality of life as significantly lower [22][23][24]. Health-related quality of life is a very important aspect of care for tumor patients, as survival rates and times for many types of cancer have increased due to medical advances, particularly in the fields of molecular biology and genetics.…”

Gesundheitsbezogene Lebensqualität bei Erwachsenen in Deutschland

“…Die Version 2 des SF-36 (SF-36V2) misst die gleichen Bereiche wie die Version 1, enthält aber teilweise Veränderungen in der Sprache und den Antwortkategorien und soll verständlicher sein und eine noch bessere interkulturelle Vergleichbarkeit gewährleisten [14,15,16]. Mittlerweile wurde der SF-36V2 außer in den USA [17,18,19,20] in weiteren englischsprachigen Ländern wie Australien [13], Neuseeland [21] und Großbritannien [14] und in nicht-englischsprachigen Ländern wie Brasilien [22], China [23], Schweden [24] und Spanien [25] angewendet. In Deutschland wurde er erstmalig im Jahr 2002 eingesetzt [26].…”

“…In Über-einstimmung mit anderen Studien [22,26] und wie schon 1998 [27] zu beobachten, berichten auch in der deutschen Bevölkerung Frauen eine geringere gesundheitsbezogene Lebensqualität als Männer. Auch in anderen Studien [21,22,24,26, 27] zeigt sich, dass Personen mit geringerem sozialem Status eine geringere gesundheitsbezogene Lebensqualität angeben.…”

“…In Übereinstimmung mit anderen Publikationen [1,22,24] Für den Vergleich der gesundheitsbezogenen Lebensqualität von vor 10 Jahren und heute wurde exemplarisch die Skala Allgemeine Gesundheit herangezogen. Da im BGS98 die gesundheitsbezogene Lebensqualität mit dem SF36V1 gemessen wurde, mussten beide Skalen, um sie vergleichbar zu machen, dem "normbased-scoring" unterzogen werden.…”

Associations among physical activity, comorbidities, depressive symptoms and health-related quality of life in type 2 diabetes

“…The Sf-36 evaluates quality of life in eight domains related to physical and mental health, and each variable ranges from 0 to 100 points, with zero being the worst and 100 the best possible score. Accuracy, reliability, validity, and adequacy of the HRQL in Brazil has already been proven (33). Comorbidity severity was evaluated with the Charlson Comorbidity Index (CCI); scores range from 0 to 37, and higher scores indicating worse comorbidity severity (34).…”