Predicting EQ-5D-5L crosswalk from the PROMIS-29 profile for the United Kingdom, France, and Germany.

BACKGROUND: EQ-5D health state utilities (HSU) are commonly used in health economics to compute quality-adjusted life years (QALYs). The EQ-5D, which is country-specific, can be derived directly or by mapping from self-reported health-related quality of life (HRQoL) scales such as the PROMIS-29 profile. The PROMIS-29 from the Patient Reported Outcome Measures Information System is a comprehensive assessment of self-reported health with excellent psychometric properties. We sought to find optimal models predicting the EQ-5D-5L crosswalk from the PROMIS-29 in the United Kingdom, France, and Germany and compared the prediction performances with that of a US model. METHODS: We collected EQ-5D-5L and PROMIS-29 profiles and three samples representative of the general populations in the UK (n = 1509), France (n = 1501), and Germany (n = 1502). We used stepwise regression with backward selection to find the best models to predict the EQ-5D-5L crosswalk from all seven PROMIS-29 domains. We investigated the agreement between the observed and predicted EQ-5D-5L crosswalk in all three countries using various indices for the prediction performance, including Bland-Altman plots to examine the performance along the HSU continuum. RESULTS: The EQ-5D-5L crosswalk was best predicted in France (nRMSEFRA = 0.075, nMAEFRA = 0.052), followed by the UK (nRMSEUK = 0.076, nMAEUK = 0.053) and Germany (nRMSEGER = 0.079, nMAEGER = 0.051). The Bland-Altman plots show that the inclusion of higher-order effects reduced the overprediction of low HSU scores. CONCLUSIONS: Our models provide a valid method to predict the EQ-5D-5L crosswalk from the PROMIS-29 for the UK, France, and Germany.

The French PROMIS-29. Psychometric validation and population reference values.

BACKGROUND: PROMIS-29 is a new generic standardized questionnaire measuring self-reported health status. It was developed as part of the Patient Reported Outcome Measurement Information System (PROMIS) in the United States. The objective of this study was to carry out the psychometric validation of a French-language version of PROMIS-29 and to establish general population reference values for France. METHODS: Quota sampling was conducted by an independent polling company (Ipsos) to obtain a general population sample (n=1,501) representative with regards to: gender, age, occupation, region, and population density of the place of residence. Data collected included the results of the questionnaires PROMIS-29 and Short Form Health Survey (SF-36), the presence of selected chronic diseases, and socio-demographic information. RESULTS: The French PROMIS-29 demonstrated excellent factorial validity, confirming the 7-factor model of the original PROMIS-29. The use of modern measurement methods indicated that the PROMIS-29 scales satisfy the important characteristics of unidimensionality and, for five of the seven composite scales, invariance across age, educational level and gender. Gender and age specific (10-year intervals) reference values were generated for PROMIS-29 use in France. CONCLUSION: The French version of PROMIS-29 is a valid and reliable measure of self-reported health status in the French population. The instrument's sensitivity to change needs to be evaluated before its use in longitudinal studies can be recommended.

Cross-cultural adaptation of a psychometric instrument: two methods compared.

Cross-cultural adaptations of questionnaires are needed in multilingual research, but little is known about the effectiveness of specific translation methods. We compared properties of two French-language adaptations of the SF36 health survey: (a) a rapid translation developed over 3 months in Geneva in 1992 (Geneva version), based on three initial translations, one synthesis, and two pretests, and (b) a comprehensive adaptation developed by the International Quality of Life Assessment Project between 1991 and 1994 (IQOLA version), which involved back-translations, focus groups, development of equidistant response options, item difficulty and quality ratings, and multiple pretests. Wordings of 34 of 36 items differed. These two instruments were administered 1 year apart to the same sample of 946 young adults. Ceiling effects were somewhat lower for the IQOLA than for the Geneva version (means 30.4% and 35.5%), and missing scores slightly less frequent (IQOLA: mean 0.5%; Geneva: 1.2%). Floor effects (means 2.7% and 2.4%), proportions of consistent respondents (93.4% and 94.0%), and internal consistency coefficients (IQOLA: 0.78-0.89, Geneva: 0.80-0.92) were similar. Factor analysis supported the existence of two main aspects of health (physical and mental) for both versions. A majority of known-group comparisons were compatible with theory, for both versions. In conclusion, the two French-language versions of the SF36 had similar psychometric properties, despite extensive differences in the development process. This suggests that a moderately resource-intensive translation may produce adequate results. More empirical research is needed to understand what translation methods yield the best results.

Validation of a French-language version of the MOS 36-Item Short Form Health Survey (SF-36) in young healthy adults.

The MOS 36-Item Short Form Health Survey (SF-36) is designed to measure 8 dimensions of health in clinical and general population settings. The main aim of this paper was to examine the reliability and validity of this instrument in young adults. A secondary aim was to document the results of a rapid translation procedure of the instrument, to be compared later to the more thorough official French adaptation. The translated survey was answered in 1992 by 1007 residents of Geneva, Switzerland, 18-44 years old, identified from health insurance rolls (82% response rate). Completion rate for all 8 dimensions of health was 95.5%. The instrument demonstrated excellent covergent (100%) and discriminant (98%) validity against pre-set criteria. Interval scaling of responses could be verified in some, but not all, items. Cronbach alpha (reliability) coefficients ranged from 0.76 to 0.92. Factorial analysis yielded 2 principal components, corresponding to mental and physical health. Thirteen of 16 correlations between health dimensions and principal components were within a pre-established range. Validation by independent clinical variables was also, with few exceptions, consistent with theory. Thus the SF-36 retained excellent psychometric properties even when used in a generally very healthy group. The careful but rapid translation procedure used in this study may be an effective alternative to full-scale cultural adaptations when resources are limited.

The French SF-36 Health Survey: translation, cultural adaptation and preliminary psychometric evaluation.

This article reports on the main developmental stages and on the preliminary psychometric assessment of the final French version of the SF-36. A standard forward/backward translation procedure was followed. When translating survey items, the emphasis was placed on conceptual equivalence. When translating response choices, we attempted to select a set of response choices that replicate the U.S. version. The distance between the response choices was checked using visual analogue scales (N = 30). The adaptation procedure also included formal ratings of the difficulty of the translation, of the quality of the translation, and of the equivalence between the American source version and the French target version. The face validity was checked during lay panel sessions at which the translated questionnaire was administered to subjects from the general public, hospital employees, and subjects with a low level of education. Standard psychometric techniques were used to evaluate the cultural adaptation of the SF-36, using data from a general population survey. The main objective of this analysis was to determine how well the scaling assumptions (summated rating or Likert-type scaling construction) of the SF-36 were satisfied. The results support the claim that the scaling properties of the French version of the SF-36 are adequate and that health outcomes may be reliably assessed using this version of the instrument.

Translating health status questionnaires and evaluating their quality: the IQOLA Project approach. International Quality of Life Assessment.

This article describes the methods adopted by the International Quality of Life Assessment (IQOLA) project to translate the SF-36 Health Survey. Translation methods included the production of forward and backward translations, use of difficulty and quality ratings, pilot testing, and cross-cultural comparison of the translation work. Experience to date suggests that the SF-36 can be adapted for use in other countries with relatively minor changes to the content of the form, providing support for the use of these translations in multinational clinical trials and other studies. The most difficult items to translate were physical functioning items, which used examples of activities and distances that are not common outside of the United States; items that used colloquial expressions such as pep or blue; and the social functioning items. Quality ratings were uniformly high across countries. While the IQOLA approach to translation and validation was developed for use with the SF-36, it is applicable to other translation efforts.

Cross-cultural comparisons of the content of SF-36 translations across 10 countries: results from the IQOLA Project. International Quality of Life Assessment.

Increasingly, translated and culturally adapted health-related quality of life measures are being used in cross-cultural research. To assess comparability of results, researchers need to know the comparability of the content of the questionnaires used in different countries. Based on an item-by-item discussion among International Quality of Life Assessment (IQOLA) investigators of the content of the translated versions of the SF-36 in 10 countries, we discuss the difficulties that arose in translating the SF-36. We also review the solutions identified by IQOLA investigators to translate items and response choices so that they are appropriate within each country as well as comparable across countries. We relate problems and solutions to ratings of difficulty and conceptual equivalence for each item. The most difficult items to translate were physical functioning items that refer to activities not common outside the United States and items that use colloquial expressions in the source version. Identifying the origin of the source items, their meaning to American English-speaking respondents and American English synonyms, in response to country-specific translation issues, greatly helped the translation process. This comparison of the content of translated SF-36 items suggests that the translations are culturally appropriate and comparable in their content.

Tests of data quality, scaling assumptions, and reliability of the SF-36 in eleven countries: results from the IQOLA Project. International Quality of Life Assessment.

Data from general population samples in 11 countries (n = 1483 to 9151) were used to assess data quality and test the assumptions underlying the construction and scoring of multi-item scales from the SF-36 Health Survey. Across all countries, the rate of item-level missing data generally was low, although slightly higher for items printed in the grid format. In each country, item means generally were clustered as hypothesized within scales. Correlations between items and hypothesized scales were greater than 0.40 with one exception, supporting item internal consistency. Items generally correlated significantly higher with their own scale than with competing scales, supporting item discriminant validity. Scales could be constructed for 93-100% of respondents. Internal consistency reliability of the eight SF-36 scales was above 0.70 for all scales, with two exceptions. Floor effects were low for all except the two role functioning scales; ceiling effects were high for both role functioning scales and also were noteworthy for the Physical Functioning, Bodily Pain, and Social Functioning scales in some countries. These results support the construction and scoring of the SF-36 translations in these 11 countries using the method of summated ratings.

The factor structure of the SF-36 Health Survey in 10 countries: results from the IQOLA Project. International Quality of Life Assessment.

Studies of the factor structure of the SF-36 Health Survey are an important step in its construct validation. Its structure is also the psychometric basis for scoring physical and mental health summary scales, which are proving useful in simplifying and interpreting statistical analyses. To test the generalizability of the SF-36 factor structure, product-moment correlations among the eight SF-36 Health Survey scales were estimated for representative samples of general populations in each of 10 countries. Matrices were independently factor analyzed using identical methods to test for hypothesized physical and mental health components, and results were compared with those published for the United States. Following simple orthogonal rotation of two principal components, they were easily interpreted as dimensions of physical and mental health in all countries. These components accounted for 76% to 85% of the reliable variance in scale scores across nine European countries, in comparison with 82% in the United States. Similar patterns of correlations between the eight scales and the components were observed across all countries and across age and gender subgroups within each country. Correlations with the physical component were highest (0.64 to 0.86) for the Physical Functioning, Role Physical, and Bodily Pain scales, whereas the Mental Health, Role Emotional, and Social Functioning scales correlated highest (0.62 to 0.91) with the mental component. Secondary correlations for both clusters of scales were much lower. Scales measuring General Health and Vitality correlated moderately with both physical and mental health components. These results support the construct validity of the SF-36 translations and the scoring of physical and mental health components in all countries studied.

The equivalence of SF-36 summary health scores estimated using standard and country-specific algorithms in 10 countries: results from the IQOLA Project. International Quality of Life Assessment.

Data from general population surveys (n = 1771 to 9151) in nine European countries (Denmark, France, Germany, Italy, the Netherlands, Norway, Spain, Sweden, and the United Kingdom) were analyzed to test the algorithms used to score physical and mental component summary measures (PCS-36/MCS-36) based on the SF-36 Health Survey. Scoring coefficients for principal components were estimated independently in each country using identical methods of factor extraction and orthogonal rotation. PCS-36 and MCS-36 scores were also estimated using standard (U.S.-derived) scoring algorithms, and results were compared. Product-moment correlations between scores estimated from standard and country-specific scoring coefficients were very high (0.98 to 1.00) for both physical and mental health components in all countries. As hypothesized for orthogonal components, correlations between physical and mental components within each country were very low (0.00 to 0.12) for both estimation methods. Mean scores for PCS-36 differed by as much as 3.0 points across countries using standard scoring, and mean scores for MCS-36 differed across countries by as much as 6.4 points. In view of the high degree of equivalence observed within each country, using standard and country-specific algorithms, we recommend use of standard scoring algorithms for purposes of multinational studies involving these 10 countries.

Cross-validation of item selection and scoring for the SF-12 Health Survey in nine countries: results from the IQOLA Project. International Quality of Life Assessment.

Data from general population surveys (n = 1483 to 9151) in nine European countries (Denmark, France, Germany, Italy, the Netherlands, Norway, Spain, Sweden, and the United Kingdom) were analyzed to cross-validate the selection of questionnaire items for the SF-12 Health Survey and scoring algorithms for 12-item physical and mental component summary measures. In each country, multiple regression methods were used to select 12 SF-36 items that best reproduced the physical and mental health summary scores for the SF-36 Health Survey. Summary scores then were estimated with 12 items in three ways: using standard (U.S.-derived) SF-12 items and scoring algorithms; standard items and country-specific scoring; and country-specific sets of 12 items and scoring. Replication of the 36-item summary measures by the 12-item summary measures was then evaluated through comparison of mean scores and the strength of product-moment correlations. Product-moment correlations between SF-36 summary measures and SF-12 summary measures (standard and country-specific) were very high, ranging from 0.94-0.96 and 0.94-0.97 for the physical and mental summary measures, respectively. Mean 36-item summary measures and comparable 12-item summary measures were within 0.0 to 1.5 points (median = 0.5 points) in each country and were comparable across age groups. Because of the high degree of correspondence between summary physical and mental health measures estimated using the SF-12 and SF-36, it appears that the SF-12 will prove to be a practical alternative to the SF-36 in these countries, for purposes of large group comparisons in which the focus is on overall physical and mental health outcomes.

Use of structural equation modeling to test the construct validity of the SF-36 Health Survey in ten countries: results from the IQOLA Project. International Quality of Life Assessment.

A crucial prerequisite to the use of the SF-36 Health Survey in multinational studies is the reproduction of the conceptual model underlying its scoring and interpretation. Structural equation modeling (SEM) was used to test these aspects of the construct validity of the SF-36 in ten IQOLA countries: Denmark, France, Germany, Italy, the Netherlands, Norway, Spain, Sweden, the United Kingdom, and the United States. Data came from general population surveys fielded to gather normative data. Measurement and structural models developed in the United States were cross-validated in random halves of the sample in each country. SEM analyses supported the eight first-order factor model of health that underlies the scoring of SF-36 scales and two second-order factors that are the basis for summary physical and mental health measures. A single third-order factor was also observed in support of the hypothesis that all responses to the SF-36 are generated by a single, underlying construct--health. In addition, a third second-order factors, interpreted as general well-being, was shown to improve the fit of the model. This model (including eight first-order factors, three second-order factors, and one third-order factor) was cross-validated using a holdout sample within the United States and in each of the nine other countries. These results confirm the hypothesized relationships between SF-36 items and scales and justify their scoring in each country using standard algorithms. Results also suggest that SF-36 scales and summary physical and mental health measures will have similar interpretations across countries. The practical implications of a third second-order SF-36 factor (general well-being) warrant further study.

Testing the equivalence of translations of widely used response choice labels: results from the IQOLA Project. International Quality of Life Assessment.

The similarity in meaning assigned to response choice labels from the SF-36 Health Survey (SF-36) was evaluated across countries. Convenience samples of judges (range, 10 to 117; median = 48) from 13 countries rated translations of response choice labels, using a variation of the Thurstone method of equal appearing intervals. Judges marked a point on a 10-cm line-representing the magnitude of a response choice label (e.g., "good" relative to the anchors of "poor" and "excellent"). Ratings were evaluated to determine the ordinal consistency of response choice labels within a response scale; the degree to which differences between adjacent response choice labels were equal interval; and the amount of variance due to response choice label, country, judge, and interaction between response choice label and country. Results confirmed the hypothesized ordering of response choice labels; the percentage of ordinal pairs ranged from 88.7% to 100% (median = 98.2%) across countries and response scales. Examination of the average magnitudes of response choice labels supported the "quasi-interval" nature of the scales. Analysis of variance (ANOVA) results supported the generalizability of response choice magnitudes across countries; labels explained 64% to 77% of the variance in ratings, and country explained 1% to 3%. These results support the equivalence of SF-36 response choice labels across countries. Departures from the assumption of equal intervals, when observed, were similar across countries and were greatest for the two response scales that are recalibrated under standard SF-36 scoring. Results provide justification for scoring translations of individual items using standard SF-36 scoring; whether these items form the same scales in other countries as they do in the United States is evaluated with tests of scaling assumptions.

Prospective study of men with clinical benign prostatic hyperplasia treated with alfuzosin by general practitioners: 1-year results.

OBJECTIVES: To investigate in men with benign prostatic hyperplasia (BPH) treated in the general practitioner setting (1) the magnitude and durability of symptom score improvement with alfuzosin; (2) the effect on patients perceived health-related quality of life (HRQL) and sexuality, (3) adverse outcomes and treatment failure; and (4) progression to acute urinary retention and prostate surgery. METHODS: A large, open outcome study was undertaken in the general practitioner setting in France, and a cohort of men with symptomatic BPH who received alfuzosin for 12 months was established. A total of 5849 patients (mean age 66.7 years) were enrolled by 1508 general practitioners in France. Men were examined at baseline and at 3 months, 6 months, and 1 year. To produce standardized outcome measures of disease-specific health status, under the conditions of routine care in the community, patients in the study completed a self-administered symptom questionnaire (score range 0 to 40) and a new, validated BPH-specific HRQL questionnaire (score range 0 to 200). Questionnaires were completed at baseline and during follow-up at 3, 6, and 12 months. RESULTS: Alfuzosin was effective in reducing symptoms; 98% (420) of severely and 85% (2479) of moderately symptomatic patients experienced improvement. At 3 months, the global symptom score was reduced by 9.49 +/- 0.08 (-53%), and this reduction persisted for the remainder of the study (-9.76 +/- 0.11). In contrast to the global reduction of symptom scores, there was a time-dependent improvement (+18.41 +/- 0.32 [+30%], +18.45 +/- 0.54 [+37%], and +23.42 +/- 0.57 [+43%] at 3, 6, and 12 months, respectively), in patients' perception of HRQL status. The magnitude of the improvement in HROL status was significantly more pronounced for those patients who had moderate or severe nocturia and daytime frequency at baseline than for those who had mild levels of the same symptoms. Sexuality score at baseline was significantly related to age and was significantly (P < 0.0001) higher in patients less than 70 years old than in older patients. Improvement in patients' perceived sexuality was significant at 12 months (P < 0.0001) and was correlated with age. CONCLUSIONS: The results of this large cohort study demonstrate the effectiveness of alfuzosin in reducing symptom severity and improving HRQL status over a 12-month period in men with BPH. It also suggests that HQRL and symptom severity are different and complementary entities. The results of the present study highlight the improvement in HRQL and patients' perceived sexuality that can be achieved in symptomatic patients with BPH receiving a 12-month course of alfuzosin therapy.

Quality-of-life impairment in neurofibromatosis type 1: a cross-sectional study of 128 cases.

BACKGROUND: Neurofibromatosis type 1 affects quality of life (QoL) through association with severe complications, impact on cosmetic features, and uncertainty of the effects of the disorder. OBJECTIVE: To evaluate the impact of the severity and visibility of neurofibromatosis type 1 on QoL. DESIGN: Monocenter, cross-sectional study. SETTING: One French academic dermatological and neurofibromatoses clinic. PATIENTS: A total of 128 adult patients with neurofibromatosis type 1. MAIN OUTCOME MEASURES: Evaluation of severity and visibility using, respectively, the Riccardi and Ablon scales. Evaluation of skin disease-specific and general QoL using, respectively, Skindex-France and SF-36 (Short Form 36 health survey) profiles controlled for sex, age, severity, and visibility. RESULTS: In a multiple regression model controlling for sex, age, and visibility, visibility remained independently associated with the alteration of 3 aspects of the skin disease-specific QoL (Skindex-France): emotions, physical symptoms, and functioning (P =.03, P =.009, and P =.002, respectively). Patients with more severe neurofibromatosis reported more effects on the following domains of their general health QoL (SF-36): physical function, bodily pain, general health perception, and vitality (P =.006, P =.03, P =.01, and P =.04, respectively). CONCLUSIONS: Neurofibromatosis type 1 has a significant impact on QoL through alteration of health and appearance. The consequences of visibility and severity from the viewpoint of patients can be evaluated using Skindex and the SF-36, respectively.

The French version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ).

We report the results of the cross-cultural adaptation and validation into the French language of two health status instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health related quality of life instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. Five hundred children were enrolled including 306 patients with JIA classified into systemic (23%), polyarticular (22%), extended oligoarticular (25%), and persistent oligoarticular (30%) subtypes, and 194 healthy children. Both instruments were reliable with intra-class correlation (ICC) coefficients for the test-retest procedure of 0.91 for the CHAQ, and 0.87 and 0.89 for the physical and psychosocial summary scores of CHQ, respectively. Agreement between parents and children evaluated for the CHAQ was high with an ICC of 0.89 for the disability index; weighted kappa coefficients for the 8 domains ranged from 0.61 to 0.72. Convergent validity was demonstrated by significant correlations with the JIA core set of variables (physician and parent global assessment, scores for active joints and joints with limited range of motion, erythrocyte sedimentation rate) for both instruments. Both CHAQ and CHQ discriminated between healthy and JIA children, but only the disease specific CHAQ questionnaire discriminated clearly between the 4 JIA subtypes. In conclusion, the French versions of the CHAQ and the CHQ are reliable, and valid health assessment questionnaires to be used in children suffering from JIA.

[Evaluation of the quality of life in clinical research in cancerology]. / Evaluation de la qualité de vie dans la recherche clinique en cancérologie.

This article clarifies the methodological aspects of quality of life evaluation and its use in cancer research. The quality of life of an individual is a complex, multidimensional, subjective concept, the perception of which is expressed optimally by individual his/herself. The tools most often used to measure the quality of life in clinical research are based on psychometry. They take at least three dimensions into account: physical, psychological and social. They must be valid, reliable and sensitive. These qualities must be verified again when translated into another language. A review of the main tools is provided. The place to be assigned to quality of life evaluation in clinical research is discussed. Routine evaluation is to be excluded because the quality of life is a subjective phenomenon that is tricky to measure and this evaluation increases the temporal and financial costs of the study, without forgetting the intrusive aspect of this action. On the other hand, as long as it contributes substantially to decision-making regarding the choice of curative or palliative treatments, or interventions necessary for the rehabilitation of the patient, it is an assessment criterion that must be included in the study.

[Preliminary analysis of the psychometric properties of the French version of an international questionnaire measuring the quality of life: the MOS SF-36 (version 1.1)]. / Analyse préliminaire des propriétés psychométriques de la version française d'un questionnaire international de mesure de qualité de vie: le MOS SF-36 (version 1.1).

The International Quality of Life Assessment (IQOLA) Project is a 4 year project initiated in 1991 to translate and adapt the Medical Outcome Study Short Form 36 item Health Survey (SF-36) in at least 15 countries. This paper reports on the preliminary psychometric assessment of the SF-36 in French (version 1.1). The validation data come from two studies: a phase IV study of 121 patients with arthritis and a phase IV study of 159 patients with angina. In both cases, the patients were surveyed using the SF-36 and a disease specific module. The main objective of this analysis was to determine how well the scaling assumptions (summated rating or Likert type scaling construction) of the SF-36 were satisfied. Item convergent validity was supported as items-scale correlation range from 0.47-0.87. Item discriminant validity was supported as all items were more correlated with their hypothesised scales than with scales measuring other concepts. Our data support the assumption that the items measuring the same concept had approximately equal variance. Items in a given scale contained about the same proportion of information about the concept being measured, as most items of any given dimension had approximately the same correlation with that dimension. The Cronbach alpha coefficient ranged between 0.79 and 0.95. The correlation between two scales was less than the reliability coefficient for those scales, and these correlations adjusted for attenuation were less than 1. These preliminary results are encouraging. They indicate that the items are linearly related to the underlying concept being measured.(ABSTRACT TRUNCATED AT 250 WORDS)