Quality of Life Research, 7, pp. 433–445 © 1998 Kluwer Academic Publishers Quality of Life Research . Vol 7 . 1998 433 Canadian-French, German and UK versions of the Child Health Questionnaire: methodology and preliminary item scaling results J. M. Landgraf, E. Maunsell, K. Nixon Speechley, M. Bullinger, S. Campbell, L. Abetz and J. E. Ware HealthAct, Boston MA, USA (J. M. Landgraf); The Health Institute, New England Medical Center, Boston, MA, USA (J. M. Landgraf, L. Abetz, J. E. Ware); Epidemiology Research Group, Université Laval, Québec, Canada (E. Maunsell); Child Health Research Institute and University of Western Ontario, London, Ontario, Canada (K. Nixon Speechley); Abteilung Für Medizinishe Psychologie, Universitatskränkenhaus Eppendorf, Hamburg Germany (M. Bullinger); Rusholme Health Centre, Department of General Practice, University of Manchester, Manchester, UK (S. Campbell) Using emerging international guidelines, stringent procedures were used to develop and evaluate Canadian-French, German and UK translations/ adaptions of the 50 item, parent-completed Child Health Questionnaire (CHQ-PF50). Multitrait analysis was used to evaluate the convergent and discrim- inant validity of the hypothesized item sets across countries relative to the results obtained for a repre- sentative sample of children in the US. Cronbach’s α coefficient was used to estimate the internal consis- tency reliability for each of the health scales. Floor and ceiling effects were also examined. Seventy-nine percent of all the item–scale correlations achieved acceptable internal consistency (0.40 or higher). The tests of the item convergent and discriminant validity were successful at least 87% of the time across all scales and countries. Equal item variance was observed 90% of the time across all countries. The reliability coefficients ranged from a low of 0.43 (parental time impact, Canadian English) to a high of 0.97 (physical functioning index, Canadian French) across all scales (median 0.80). Negligible floor effects were observed across countries. Noteworthy ceiling effects were observed, as expected, for the hypothesized physical scales (mean effect 73%). Conversely, fewer ceiling effects were observed for the psychosocial scales (range 3–17% behaviour– parental emotional impact). The item–scaling results obtained in these pilot studies support the psycho- metric properties of the American-English CHQ-PF50 and its respective translations. Qual. Life Res. 7:433–445 © 1998 Kluwer Academic Publishers Key words: Child Health Questionnaire; translation; multitrait analysis. Introduction and background The Child Health Assessment Project was initiated in 1990. The primary research objective was to advance methods for measuring the physical and psychosocial health status and well-being of children and adoles- cents. The Child Health Questionnaire (CHQ), a tool for measuring and comparing the health of general and specific groups of children and estimating the benefits of alternative treatments, is the principal outcome of this effort. 1–8 Rigorous cross-cultural trans- lation and evaluation of the CHQ using emerging international guidelines 9–14 and standardized analytic methods prior to widespread release was an integral component of its development and validation. 15–18 A noteworthy benefit of translation work prior to an instrument’s standardization and dissemination is the identification and adaptation of problem items, ambiguous phrases, idiomatic expressions and conceptual inequivalences. Because the instrument is not yet widely available, enhancements are easily integrated into the ongoing development and evalu- ation efforts, resulting in a less ambiguous and more culture-free version of the original instrument. 19,20 Finally, early cross-cultural exchanges present a means for refining and communicating the conceptual model used in the construction of an instrument. Overcoming potential misinterpretations requires the developer to provide a clear exposition of the framework of the instrument rather than relying on a tacit understanding of his/her intent. The CHQ was originally constructed as a full- length 98 item questionnaire. In response to industry demands for instruments of more practical length, a