Canadian-French, German and UK versions of the Child Health Questionnaire: methodology and preliminary item scaling results

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1 Qulity of Life Reserch, 7, pp Cndin-French, Germn nd UK versions of the Child Helth Questionnire: methodology nd preliminry item scling results J. M. Lndgrf, E. Munsell, K. Nixon Speechley, M. Bullinger, S. Cmpbell, L. Abetz nd J. E. Wre HelthAct, Boston MA, USA (J. M. Lndgrf); The Helth Institute, New Englnd Medicl Center, Boston, MA, USA (J. M. Lndgrf, L. Abetz, J. E. Wre); Epidemiology Reserch Group, Université Lvl, Québec, Cnd (E. Munsell); Child Helth Reserch Institute nd University of Western Ontrio, London, Ontrio, Cnd (K. Nixon Speechley); Abteilung Für Medizinishe Psychologie, Universittskränkenhus Eppendorf, Hmburg Germny (M. Bullinger); Rusholme Helth Centre, Deprtment of Generl Prctice, University of Mnchester, Mnchester, UK (S. Cmpbell) Using emerging interntionl guidelines, stringent procedures were used to develop nd evlute Cndin-French, Germn nd UK trnsltions/ dptions of the 50 item, prent-completed Child Helth Questionnire (CHQ-PF50). Multitrit nlysis ws used to evlute the convergent nd discriminnt vlidity of the hypothesized item sets cross countries reltive to the results obtined for representtive smple of children in the US. Cronbch s α coefficient ws used to estimte the internl consistency relibility for ech of the helth scles. Floor nd ceiling effects were lso exmined. Seventy-nine percent of ll the item scle correltions chieved cceptble internl consistency (0.40 or higher). The tests of the item convergent nd discriminnt vlidity were successful t lest 87% of the time cross ll scles nd countries. Equl item vrince ws observed 90% of the time cross ll countries. The relibility coefficients rnged from low of 0.43 (prentl time impct, Cndin English) to high of 0.97 (physicl functioning index, Cndin French) cross ll scles (medin 0.80). Negligible floor effects were observed cross countries. Noteworthy ceiling effects were observed, s expected, for the hypothesized physicl scles (men effect 73%). Conversely, fewer ceiling effects were observed for the psychosocil scles (rnge 3 17% behviour prentl emotionl impct). The item scling results obtined in these pilot studies support the psychometric properties of the Americn-English CHQ-PF50 nd its respective trnsltions. Qul. Life Res. 7: Kluwer Acdemic Publishers Key words: Child Helth Questionnire; trnsltion; multitrit nlysis. Introduction nd bckground The Child Helth Assessment Project ws initited in The primry reserch objective ws to dvnce methods for mesuring the physicl nd psychosocil helth sttus nd well-being of children nd dolescents. The Child Helth Questionnire (CHQ), tool for mesuring nd compring the helth of generl nd specific groups of children nd estimting the benefits of lterntive tretments, is the principl outcome of this effort. 1 8 Rigorous cross-culturl trnsltion nd evlution of the CHQ using emerging interntionl guidelines 9 14 nd stndrdized nlytic methods prior to widespred relese ws n integrl component of its development nd vlidtion A noteworthy benefit of trnsltion work prior to n instrument s stndrdiztion nd dissemintion is the identifiction nd dpttion of problem items, mbiguous phrses, idiomtic expressions nd conceptul inequivlences. Becuse the instrument is not yet widely vilble, enhncements re esily integrted into the ongoing development nd evlution efforts, resulting in less mbiguous nd more culture-free version of the originl instrument. 19,20 Finlly, erly cross-culturl exchnges present mens for refining nd communicting the conceptul model used in the construction of n instrument. Overcoming potentil misinterprettions requires the developer to provide cler exposition of the frmework of the instrument rther thn relying on tcit understnding of his/her intent. The CHQ ws originlly constructed s fulllength 98 item questionnire. In response to industry demnds for instruments of more prcticl length, 1998 Kluwer Acdemic Publishers Qulity of Life Reserch. Vol

2 J. M. Lndgrf et l. 50 item, prent-completed short form (CHQ-PF50), ws empiriclly derived from the full-length version. The CHQ-PF50 ws stndrdized for use in the Generl Socil Survey (GSS), 21 representtive household survey conducted in the US between 1994 nd The normtive dt from the prents of children completing the CHQ-PF50 were recently published in the CHQ user mnul. 3 This pper hs two objectives: (1) To describe the trnsltion methodology used to produce the Cndin-French, Germn nd UK developmentl versions of the CHQ-PF50; (2) To present the preliminry psychometric results from pilot projects in these countries nd in representtive smple of children in the US. The full-length 98 item version of the CHQ ws trnslted nd fielded in the three countries. However, to mintin comprbility with the stndrdized Americn-English version, the psychometric results re reported for the 50 item short form only. Conceptul frmework nd content of the CHQ Description of the CHQ The CHQ is comprehensive, multidimensionl helth ssessment tool designed to mesure two fundmentl components of child nd dolescent helth: physicl nd psychosocil functioning nd well-being. 1 8 Tble 1 provides summry of the 14 concepts cptured in the CHQ nd the number of items per concept. There re ten helth-relted qulity of life concepts trgeted t the child: physicl functioning, bodily pin/discomfort, limittions in schoolwork nd ctivities with friends due to physicl helth, generl helth perceptions, chnge in helth, limittions in schoolwork nd ctivities with friends due to emotionl/behviourl difficulties, mentl helth, generl behviour nd self-esteem. These concepts re recognized s being essentil components of children s helth-relted qulity of life Children live within fmily structure nd re influenced by these reltionships. Often prents function s gtekeepers of their children s helth. Reserch hs demonstrted strong link between prentl ccess to cre nd children s helth nd well-being. 4,33,34 For these resons, the 50 item, prent-completed version of the CHQ lso includes four concepts designed to mesure the emotionl impct of the child s helth on the prentl respondent: the degree he/she feels limited in personl time due to the child s helth, the degree of limittions in fmily ctivities nd the overll cohesion of fmily reltionships (for complete exposition of the conceptul frmework of the CHQ, see Lndgrf et l. 3 (pp.33 38)). All of the scles were constructed nd scored using Likert s method of summted rtings. 35 The summted rting method is dvntgeous becuse scle scoring is simple nd the results re reproducible without compromising the internl consistency, relibility or vlidity of the scle. For ese of interprettion cross ll the helth scles, the rw scores re converted to scle with higher scores indicting better functioning nd well-being. Methods Instrument trnsltion The trnsltion protocol ws bsed on emerging interntionl guidelines in helth outcomes reserch, 9 14 with specific ttention to issues unique to the ssessment of peditric popultions (e.g. representtion by both pternl nd mternl trnsltors). 36 Every effort ws mde to ensure comprbility in the trnsltion stndrds for the Cndin-French, Germn nd UK versions of the CHQ. However, the projects reported in this pper represent independent efforts tht were conducted t different times during the development nd stndrdiztion of the CHQ. At minimum, the trnsltion procedure for ech country included both forwrd nd bckwrd itertions of the CHQ. 19,20 The number of initil forwrd trnsltions produced for ech country vried nd ws bsed on the time nd resources vilble. When more thn one forwrd trnsltion ws produced for country, hrmoniztion meeting ws held with the trnsltors, country investigtors nd the CHQ developer to identify potentil problems in the item wording nd phrses nd to reconcile differences so s to rrive t the best possible forwrd version of the CHQ in the trgeted lnguge (e.g. Cndin French). For ech trnsltion, the intent ws to cpture the connottive mening of the originl items nd phrses while tking into ccount possible culturl uniqueness. Conceptul equivlence hs been recognized by socil scientists nd dult nd child helth reserchers s n essentil criterion for developing nd evluting questionnires nd survey tools intended for cross-culturl ppliction. 9 14,19,20 The primry rchitect of the CHQ (J.L.), formlly trined nd experienced in children s cquisition of lnguge 37,38 nd issues in cross culturl communiction nd 434 Qulity of Life Reserch. Vol

3 Tble 1. Concepts in the CHQ-PF50 nd interprettion of low nd high scores Cndin-French, Germn nd UK versions of the CHQ Number Concepts of items Low score High score Physicl functioning 6 Child is limited lot in performing Child performs ll types of physicl ll physicl ctivities, including ctivities, including the most vigorous, self-cre, due to physicl helth without limittions due to helth Role/Socil-physicl 2 Child is limited lot in schoolwork Child hs no limittions in schoolwork or or ctivities with friends due to ctivities with friends due to physicl physicl helth helth Generl helth 6 Prent believes child s helth is Prent believes child s helth is excellent perceptions b poor nd likely to get worse nd will continue to be so Bodily pin 2 Child hs extremely severe, Child hs no pin or limittions due to frequent nd limiting bodily pin pin Prentl time impct 3 Prent experiences lot of Prent does not experience limittions in limittions in time vilble for time vilble for personl needs due to personl needs due to child s child s physicl nd/or psychosocil physicl nd/or psychosocil helth helth Prentl emotionl 3 Prent experiences gret del Prent does not experience feelings of impct of emotionl worry/concern due emotionl worry/concern due to child s to child s physicl nd/or physicl nd/or psychosocil helth psychosocil helth Role/Socil-emotionl/ 3 Child is limited lot in schoolwork Child hs no limittions in schoolwork or behviourl c or ctivities with friends due to ctivities with friends due to emotionl or emotionl or behviourl problems behviourl problems Self-esteem 6 Child is very disstisfied with Child is very stisfied with bilities, looks bilities, looks, fmily/peer fmily/peer reltionships nd life overll reltionships nd life overll Mentl helth 5 Child hs feelings of nxiety nd Child feels peceful, hppy nd clm ll depression ll of the time of the time Generl behviour b 6 Child very often exhibits ggressive, Child never exhibits ggressive, immture, delinquent behviour immture, delinquent behviour Fmily ctivities 6 The child s helth very often limits The child s helth never limits or nd interrupts fmily ctivities or is interrupts fmily ctivities nor is source source of fmily tension of fmily tension Fmily cohesion b 1 Fmily s bility to get long is Fmily s bility to get long is rted rted poor excellent Chnge in helth 1 Child s helth is much worse Child s helth is much better now thn now thn 1 yer go 1 yer go A 4 week recll period is used for ll scles except for the generl helth perceptions, fmily cohesion nd chnge in helth. No recll period is used for generl helth perception or fmily cohesion. The recll system for chnge in helth is compred to lst yer. b Includes stnd-lone globl item tht uses five-level response continuum rnging from excellent to poor. c Counted s two seprte concepts lthough items re combined into one scle. Qulity of Life Reserch. Vol

4 J. M. Lndgrf et l. trnsltion, served s the principl consultnt to ll three projects. During hrmoniztion of the bck trnsltions of the CHQ, we mde use of informtion obtined from extensive empiricl tests conducted previously by Wre et l. 9,10 s prt of the Interntionl Qulity of Life Project (IQOLA) designed to evlute trnsltions of the dult SF-36 Helth Survey psychometriclly. 42 The tests included evluting the ordinlity nd equlity of the response intervls. Thus, when pproprite, resolutions of problemtic response options in the CHQ tht re equivlent to those found in the Americn-English version of the SF-36 Helth Survey were dopted. For some of these discrepncies, however, deprtures in the wording were wrrnted, due to the culturl nunces of ssessing children nd dolescents reltive to dults. The specific detils regrding the trnsltion procedures, project informtion nd smpling strtegies for ech country re presented in chronologicl order. Germny. The methodology employed for the developmentl Germn version of the CHQ ws not s extensive s the protocol dopted for subsequent trnsltions due to the time constrints of the Germn project in which the CHQ ws fielded. 43 The purpose of the project ws to ssess the potentil impct of irport noise on the helth-relted qulity of life of children nd their fmilies. The impending reloction of regionl irport, the mjor focus of the study, did not llow sufficient time for thorough trnsltion or pre-test of Germn version of the CHQ. Thus, single forwrd trnsltion of the CHQ ws conducted in 1993 by the Germn IQOLA project scientist overseeing the Germn trnsltion of the SF-36 Helth Survey. 44 The developmentl Germn version of the CHQ ws then bck trnslted by n independent bilingul collegue nd reviewed for conceptul equivlence by the principl rchitect of the CHQ. 3 No mjor recommendtions for chnges in the items, phrsing or response options to the Americn version were mde t the time the CHQ ws fielded in the irport noise project. UK. The ngliciztion of the CHQ ws conducted in Mnchester s prt of study to ssess sthmtic children receiving cre t fmily clinic. 45 The project ws conducted between 1993 nd Ech item in the CHQ ws reviewed for comprbility with the colloquil expressions used in the UK. It ws determined by the interdisciplinry tem tht only single item in the generl helth scle would need modifiction. In the US version of the generl helth scle, the item is worded, My child ws once so sick I thought he/she might die. In the UK the term sick refers to n cute symptom (e.g. vomiting). The intent of the Americn wording, however, is to scertin whether child hs experienced severe or lifethretening illness. To cpture this intent more ccurtely, yet reflect the colloquil expression of the country, the item ws reworded ( My child ws once so ill I thought he/she might die ). Once other minor modifictions in spelling were mde, the CHQ ws completed by 20 prents of mixed socioeconomic bckground. The context of the individul responses ws evluted reltive to the intended mening of the items by conducting debriefing interviews with ech respondent upon completion of the CHQ. The interviewer queried the prent bout the visul formt of the CHQ, difficult items or phrses, the ese of completion, the relevnce nd sufficiency of choices, the intrusiveness or offensiveness of the items nd the importnce of the doctor hving ccess to the informtion obtined from the CHQ. Cnd. The Cndin-French trnsltion work begn in 1994 nd the initil developmentl form ws prepred by two professionl trnsltors nd one ly trnsltor with extensive experience in the design nd dministrtion of reserch questionnires in Frenchspeking Cndins.(In the cse of English-speking Cndins, the Americn-English CHQ ws judged to be pproprite nd cceptble by the trnsltion pnel nd reserch investigtors.) The inclusion of ly trnsltor expnds on the emerging guidelines 9 14 by introducing him/her erlier in the trnsltion process. We believed this enhncement would help to ensure tht the use of common ly lnguge ws interwoven into the process itself rther thn using the strtegy employed by others wherein the ly representtive evlutes the qulity of the trnsltion upon its completion In ddition, the use of three trnsltors mde it esier to identify those items for which there ws consensus nd those tht required dditionl work to chieve hrmony. Discrepncies between the three itertions were discussed nd reconciled into single Cndin-French version during n extensive fce to fce meeting with the primry CHQ developer, the trnsltors nd the bilingul investigtors. The reconciled forwrd trnsltion ws then bck trnslted into English by two ly bilinguls not ssocited with the project or the helth outcomes field. Agin, our objective in selecting non-professionl trnsltors ws to gurd ginst lnguge not commonly understood by the verge Cndin prent. The two bck trnsltions were judged to be conceptully equivlent to the originl text by both the principl rchitect of the CHQ nd the Cndin reserch tem. Pre-testing ws then conducted with Cndin-French 436 Qulity of Life Reserch. Vol

5 Cndin-French, Germn nd UK versions of the CHQ nd English spekers to evlute the cceptbility nd ese of understnding of the respective Cndin- French nd Americn-English versions of the CHQ. Four fmilies prticipted, two with children ged < 10 yers nd two whose children were between 10 nd 16 yers of ge. Similr to the UK debriefing interviews, upon completion of the CHQ, the respondents were queried bout the visul formt of the CHQ, difficult items or phrses, the ese of completion, the relevnce nd dequcy of the response options. Dt collection strtegies nd description of the smples Summry descriptions of ech country s smple nd the corresponding dt collection strtegy re presented. Tble 2 provides summry of the sociodemogrphic chrcteristics of the respondents in ech country. The demogrphic vribles included child ge, gender nd ethnicity nd prent ge, gender, ethnicity, eduction nd work sttus. Germny. The Germn dt were collected for two groups: children nd dults living in the vicinity of two irports in Munich nd control subjects, people living in two towns wy from the irports. 43 The prents in the Germn smple were between 25 nd 50 yers of ge. The children rnged from 8 to 12 yers of ge. A mil out/mil bck dministrtion ws used. Of the 271 Germn respondents, dt from the prents of 259 children were included in the finl nlyses. Twelve children were excluded from the nlyses due to missing dt (4%). The men child ge ws 10 yers old (rnge: 8 12 yers). Fifty-four percent of the children were femles. The CHQ ws completed primrily by mothers (86%) whose medin ge ws 39 yers. Almost ll of the respondents were Cucsin (94%). Most of the respondents were mrried (88%) nd hd completed t lest 9 yers of schooling. Thirty-three percent of the respondents were working outside the home in full or prt-time positions. UK. The dt were collected by clinic stff ssocited with the Deprtment of Generl Prctice, University of Mnchester during routine office visits. Prents or gurdins of children dignosed with cute respirtory disorders nd between the ges of 5 nd 17 yers of ge were invited to prticipte. Of the 100 respondents in the British smple, 91 children were included in the finl nlyses; nine children were excluded due to missing dt (9%). The men child ge ws 8.9 yers old (rnge 5 13 yers) nd 54% were mles. The CHQ ws completed primrily by mothers (93%) whose medin ge ws 36 yers (rnge yers). The mjority of the respondents were Cucsin (78%). Respondent work nd mritl nd eductionl sttus were not vilble. Cnd. Both the Cndin-English nd -French CHQ dt were collected from the prents of childhood cncer survivors prticipting in fesibility study conducted s prt of the Cndin Childhood Cncer Tble 2. Smple chrcteristics Cnd Germny UK English Cndin French Cndin US Demogrphics (n = 259) (n = 91) (n = 54) (n = 16) (n = 398) Child Men ge in yers (rnge) 10 (8 12) 8.9 (5 13) 12 (6 16) 11 (8 14) 12 (4 19) Femle (%) Prent Men ge in yers (rnge) 39 (25 52) 36 (19 73) 39 (29 49) 40 (32 47) 37 (19 55) Femle (%) Cucsin (%) Working full- or prt-time (%) Mrried (%) Some college or more completed (%) Informtion not collected. Qulity of Life Reserch. Vol

6 J. M. Lndgrf et l. Surveillnce nd Control Progrm (CCCSCP). 46 One purpose of the CCCSCP is to ssess psychosocil lte effects mong childhood cncer survivors. Dt from English-speking prents were gthered in the provinces of Albert, Mnitob, Nov Scoti nd Ssktchewn while the Cndin-French dt were gthered in Québec. The child prticipnts were t lest 5 yers post-dignosis t the time of this study nd rnged from 5 to 17 yers of ge. The types of cncer included leukemi, lymphom nd centrl nervous system nd bone cncers. A mil out/mil bck mode of dministrtion ws used. The response rte ws 72% (123 of 170 eligibles) in the English provinces. In Quebec, 83% of the eligible prents responded. Fifty-four English- nd 16 French-Cndin prents responded to the questionnire; three English- Cndin children (5.5%) were excluded in this nlysis due to missing dt. Among English spekers the men child ge ws 12 yers (rnge 6 16 yers) nd 46% were femles. The CHQ ws completed primrily by mothers (91%) whose medin ge ws 39 yers (rnge yers). Ninety-three percent of the English respondents were primrily of Cucsin origin (English, Polish, Germn, Scottish, Irish, Itlin, French, Dutch nd Ukrinin). Seventy-three percent of the English respondents were working outside the home in full or prt-time positions, 78% were mrried nd 50% hd completed t lest 12 yers of forml eduction (rnge 2 23 yers). The men child ge for the French-speking smple ws 11 yers old (rnge 8 14 yers) nd 69% were femles. The CHQ ws completed primrily by mothers (88%) whose medin ge ws 40 yers (rnge yers). The mjority of respondents (88%) were of French origin. Seventy-five percent of the Frenchspeking respondents were working outside the home, 69% were mrried nd 50% hd completed 12 yers of forml eduction (rnge 5 19 yers). US. The respondents were drwn from dtbse of people who hd completed ntionl functionl sttus survey s prt of the 1990 GSS, n nnul study conducted mong rndom smple of the noninstitutionlized dult US popultion by the Ntionl Opinion Reserch Center (NORC). Bsed on the demogrphic informtion received from 1,372 households in 1990, 632 (46%) households included children between the ges of 5 nd 19 yers of ge in Of these, 572 (91%) fmilies were locted nd miled the CHQ; 420 households responded (73% of the fmilies locted). Eight households reported no eligible child in the fmily nd one child ws reported to be decesed. Thus, totl of 411 (72%) respondents completed the CHQ. In the cse of households contining more thn one child, the prents were sked to complete the questionnire for the child hving the most recent birthdy. The prticipnts were given $5.00 incentive to complete the CHQ. Of the 411 US respondents, 13 were excluded due to missing dt (3%) for finl smple of 398 children. The medin child ge ws 12 yers (rnge 4 19 yers), 55% percent were mles nd 82% were Cucsin. The mjority of the children (246 or 62%) were reported to hve one or more chronic conditions. The conditions, problems nd disorders included ttentionl problems (20%), vision problems (19%), llergies (18%), behviour problems (15%), sthm (12%), lerning problems (12%), speech problems (12%), nxiety (5%), depression (5%), respirtory problems excluding sthm (4%), hering problems including defness (4%), developmentl dely (3%) orthopedic problems (3%), epilepsy (1%) nd sleep disturbnces (2%). The respondents were primrily the biologicl prents of the trget child (94%), women (83%), mrried (77%) nd working outside the home (76%). The respondents medin ge ws 37 yers (rnge yers). Thirty-nine percent of the respondents hd high school diplom or less, 25% hd some college or voctionl school trining nd 25% hd college diplom or hd ttended grdute school. Tests of scling ssumptions The item internl consistency, item discriminnt vlidity nd scle level internl consistency relibilities were evluted. The score distributions nd floor nd ceiling effects were lso exmined. All of the psychometric computtions were performed using the Revised Multitrit Anlysis Progrm (MAP-R) 47,48 which ws derived from ANLITH (Anlysis of Itemtest Homogeneity Progrm). Multitrit nlysis tests the hypothesized item groupings for the CHQ scles by exmining the internl consistency relibility of the items. The four scling criteri (the item internl consistency, item discriminnt vlidity, equl item vrince nd equl item totl correltions) re discussed. The item internl consistency is demonstrted when ech item in hypothesized scle is substntilly linerly relted to the underlying concept being mesured. An item scle correltion, corrected for n overlp of 0.40, hs been recommended. 49 Wheres in tests of the item internl consistency the expected result is high item scle correltions for hypothesized sets of items (i.e. scle), the opposite is true in tests of the item discriminnt vlidity. 438 Qulity of Life Reserch. Vol

7 Cndin-French, Germn nd UK versions of the CHQ Generlly, the lower the correltion of n item outside its hypothesized set with items from other scles the greter the scling criterion for discriminnt vlidity is stisfied. The item discriminnt vlidity does not directly support the overll bility of n instrument to distinguish or discriminte cross conditions; rther it provides evidence of the conceptul logic for plcing n item within prticulr scle reltive to other scles within n instrument. To be counted s scling success, the item scle correltions must be > 2 SE with the hypothesized scles thn with other scles. 50 The significnce of the difference between two item scle correltions is determined in prt by the smple size. Becuse our Cndin smple ws drwn from pilot study nd therefore reltively smll, correltions between items nd their hypothesized scles tht were t lest 1 SE higher thn those with other scles were lso counted s meeting the criterion for item discriminnt vlidity. In tests of equl item vrince, items mesuring spects of the sme construct re ssessed to determine whether they demonstrte pproximtely equl vrince (within 0.2 of the medin item scle correltion). If they do, it is considered unnecessry to stndrdize or weight items prior to ggregting them in the sme scle. The summted rting pproch to scle construction seeks to simplify the complexities ssocited with differentil item weighting by ssigning the sme scoring vlue (1) to ll items within prticulr scle. The underlying theoreticl rgument posits tht if items contribute substntilly to the totl score they provide pproximtely the sme mount of informtion bout the concept being mesured nd thereby eliminte ny need for reweighting. The ssumption is met if the correltions for ll items within scle re pproximtely equl to one nother. This test principle is tntmount in the construction nd evlution of new scles or the development of short-form lterntives for prticulr instrument. Evidence of equlity mong the item scle correltions for the CHQ-PF50 is provided in gret detil elsewhere 3 nd is therefore not repeted here. A review of the Germn, UK nd Cndin dt supports these findings nd is vilble upon request from the uthor. Floor nd ceiling effects nd the percentge of children chieving the lowest nd highest possible scores, respectively, were lso studied. The internl consistency relibility for ech scle ws estimted using Cronbch s α coefficient. 51 Scles with relibilities of t lest 0.50 but preferbly 0.70 nd greter re considered sufficiently relible for use in group comprisons. 52,53 The α coefficient represents the men of ll possible split-hlf relibility estimtes djusting for scle length nd hs been shown in previous studies to pproximte test retest estimtes when scling ssumptions re well met Results Item internl consistency Tble 3 presents summry of the item scling results. In columns 1 4 we present the rnge of itemscle correltions observed for ech scle cross the four countries. To summrize (not shown), the medin item scle correltion observed in the Germn smple ws 0.52, 0.61 for the UK smple, 0.53 in the Englishspeking Cndin smple, 0.66 in the Frenchspeking Cndin smple nd 0.60 in the US smple. Thus, the mjority of the items cross ll five smples exceeded the minimum > 0.40 requirement for this scling criteri. Specificlly, the percentge of the items meeting or exceeding this requirement were s follows: Germny 76%, UK 85%, English-speking Cndins 73%, French-speking Cndins 81% nd US 87%. Item discriminnt vlidity nd equl item vrince The scling results for the tests of the item discriminnt vlidity (Tble 3, columns 5 16) re presented in two wys. First, columns 9 12 present successes/ totl, tht is the numertor represents the ctul number of item scle correltions > 2 SE nd the denomintor represents the totl number of tests conducted. The denomintor differs for ech scle becuse it is clculted using the number of items in scle multiplied by the totl number of scles fielded in the smple. For exmple, in the Germn smple only nine scles were fielded. The physicl functioning scle is comprised of six items. Thus, 6 9 = 54. Second, the percentges of the overll success rtes re presented in columns The overll success rtes were very high cross the four countries. In the Germn, UK nd US smples, perfect or ner perfect rtes ( 96%) were observed for ll but few of the CHQ scles (ten in the U.K smple nd eight in the U.S nd Germn smples). The success rtes for the Cndin-English smple were bit lower thn those observed for the French spekers. The success rtes rnged from 100% for three scles to 60% (prentl time impct) in the English smple. Among the French spekers, the success rtes for six Qulity of Life Reserch. Vol

8 J. M. Lndgrf et l. Tble 3. Results of the item scling tests for the CHQ-PF50 scle cross the Germn, UK, Cndin nd US smples Item internl consistency b Item discriminnt vlidity c Success/Totl d % scling success c Germn UK Cnd US Germn UK Cnd US Germn UK Cnd US Germn UK Cnd US English French English French English French English French CHQ-PF50 scles (n = 259) (n = 91) (n = 51) (n = 16) (n = 397) (n = 259) (n = 91) (n = 51) (n = 16) (n = 397) (n = 259) (n = 91) (n = 51) (n = 16) (n = 397) (n = 259) (n = 91) (n = 51) (n = 16) (n = 397) Physicl function /54 54/54 46/60 54/54 60/ (k = 6) f Pin (k = 2) /18 18/18 20/20 18/18 20/ Role/Socil-physicl /18 18/18 20/20 18/18 20/ (k = 2) Generl helth /54 53/54 42/60 47/54 60/ perceptions (k = 6) Role/Socil-emotion/ /27 27/27 30/30 25/27 30/ behviour (k = 3) g Mentl helth /45 43/45 30/30 25/27 30/ (k = 5) Behviour (k = 6) /45 45/45 45/50 26/45 48/ Self-esteem (k = 6) /54 54/54 54/60 40/54 60/ Prentl emotionl /27 27/27 24/30 25/27 25/ impct (k = 3) Prentl time impct /27 27/27 18/30 22/27 29/ (k = 3) Fmily ctivities g g 0.25 g 0.49 g g (k = 6) g g g 53/70 g 50/60 g g 76 g 83 Single items (fmily cohesion, globl behviour nd chnge in helth) re not included in these nlyses. b Rnge of correltions between items within hypothesized scle. c Rnge of correltions between items nd other CHQ scles. d Success (numertor) refers to items tht correlte > 2 SE higher with their hypothesized scle thn with oither CHQ scles. Totl (denomintor) refers to the numberof items in scle multiplied by the number of other scles in the mtrix (for exmple, physicl function consists of six items nd there re ten other scles, thus 6 10 = 60). e Percentge of items correlting higher with their hypothesized scle thn with other CHQ scles. k = number of items in the scle. g Scle not fielded in this smple. f 440 Qulity of Life Reserch. Vol

9 Cndin-French, Germn nd UK versions of the CHQ Tble 4. Results of the relibility of estimtes for the CHQ-PF50 b scles cross the Germn, UK, Cndin nd US smples Cnd Germny UK English French US CHQ-PF50 scles (n = 259) (n = 91) (n = 54) (n = 16) (n = 398) Physicl functioning (k =6) c Bodily pin (k = 2) Role/Socil-physicl (k = 2) d 0.92 Generl helth perceptions (k = 6) Role/Socil-emotionl/behviourl (k = 3) Mentl helth (k = 5) Generl behviour (k =6) e Self-esteem (k = 6) Prentl emotionl impct (k = 3) Prentl time impct (k = 3) Fmily impct (k =6) f f 0.63 f 0.59 Internl consistency relibility (Cronbch s α). b Single items (including chnge in helth nd fmily cohesion) re not included in these nlyses. c k = number of items in the scle. d Relibility not clculted due to lck of vrince between items. e k = 5 for Cndin, UK nd Germn smples; globl behviour item missing. f Scle not fielded in this smple. of the scles were 93%. The lowest success rte for ny of the CHQ scles (58%, behviour) ws observed in this smple. α coefficients Tble 4 presents the α coefficient results. In the Germn smple, seven CHQ scles met the criterion for the group level comprisons (rnge ). The α coefficients for the three remining scles (generl helth perceptions, behviour nd prentl emotionl impct) were 0.60, 0.66 nd 0.63, respectively. Nine of the CHQ scles exceeded the minimum α coefficients for group level comprisons (medin 0.81) in the UK smple. The lowest α coefficient ws observed for the generl helth scle (0.61). In the Cndin-English smple, the α coefficients for six of the scles exceeded 0.70 with two scles just missing the cut-off (0.69; mentl helth nd behviour). A low correltion of 0.43 ws observed in this smple for the prentl time impct scle. The α coefficients were > 0.76 in the Cndin-French smple for ll but three of the CHQ scles. The exceptions for this smple were 0.65 (bodily pin nd self-esteem) nd 0.52 (generl behviour). The results in these smples re consistent with those chieved in the US. Nine of the CHQ scles fielded in the US smple exceeded the minimum α coefficients for group level comprisons (medin 0.80). As reported for the previous smples, reltively low α coefficient ws observed for the generl helth scle (0.66). A low coefficient ws lso observed in the US smple for the limittions in fmily ctivities scle (0.59). Floor nd ceiling effects Tble 5 presents the floor nd ceiling effects. No floor effects were observed for the Germn smple. Of note, however, were the high ceiling effects observed for physicl functioning (82%) nd the two role/socil limittions scles (89% physicl nd 70% emotionl/ behviourl). A moderte effect ws observed for bodily pin/discomfort (28%), prentl time impct (34%) nd emotionl (12%) nd self-esteem (11%). Other ceiling effects were negligible (< 2%). With the exception of single scle in the UK smple, (role/socil limittions-physicl, 6%) negligible floor effects were observed. High ceiling effects were observed for the two role/socil limittions scles (74% physicl nd 76% emotionl/behv- Qulity of Life Reserch. Vol

10 J. M. Lndgrf et l. Tble 5. Summry of the floor nd ceiling effects for the CHQ-PF50 scles cross the Germn, UK, Cndin nd US smples PF BP RP GH REB MH BE SE PEI PTI FA % % % % % % % % % % % % % % % % % % % % % % floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling floor ceiling b b b b Germny UK Cnd English French b b US Single litems (fmily cohesion nd chnge in helth) re not included in this nlysis. b Scle not fielded in this smple. PF, physicl functioning; BP, bodily pin; RP, role/socil limittions-physicl; GH, generl helth perceptions; REB, role/socil limittions-emotionl/behviourl; MH, mentl helth; BE, behviour; SE, self-esteem; PEI, prentl emotionl impct; PTI, prentl time impct; FA, fmily ctivities. iourl). A moderte effect ws observed for physicl functioning (31%), bodily pin/discomfort (36%) nd prentl time impct (58%). The only floor effects observed in the Cndin smples were for the two role/socil limittions scles (2% ech) mong English spekers nd single role/ socil scle (physicl) in the French-speking smple (6%). In generl, more ceiling effects were observed for the English spekers reltive to the French spekers. Of note were the high percentges of respondents reporting more optiml functioning (i.e. higher ceiling effects) for the physicl functioning scle, bodily pin/discomfort nd the two role/socil limittions scles. The nlyses bsed on the combined smple (n = 67) did not chnge overll findings mterilly. With the exception of one scle (prentl time impct 4%) in the US smple, negligible floor effects were observed. Conversely, s expected nd observed in the other smples, high ceiling effects (indicting no limittions), were observed for some scles. These included physicl functioning (85%), the two role/socil limittions scles (86% physicl nd 78% emotionl/behviourl), prentl time impct (61%) nd bodily pin/discomfort (40%). A moderte effect ws observed for self-esteem (15%) nd prentl emotionl impct (20%). Discussion The primry objectives of this pper were to describe the procedures used to trnslte nd evlute developmentl Germn, UK nd Cndin-French versions of the 50 item, prent-completed CHQ (CHQ-PF50) 3 nd to present the preliminry scling results. The empiricl dt support the structurl integrity of these instruments t both the item nd scle levels nd re consistent with the item scling results obtined for the CHQ in condition groups nd clinicl tril smples in the US. 1 3,15 18 It is importnt to note tht the most problemtic scle, irrespective of country including the US, ws the generl heth perceptions scle. The overll results obtined for this scle re not surprising s it ws purposefully designed to be heterogenous. The intent of the developers ws to offset potentil cquiescent response bis by mking it bit more difficult for respondents to complete. The results chieved for the developmentl Germn version re noteworthy. It ws decided, however, tht since only one forwrd nd one bckwrd trnsltion process ws used, the Germn version my benefit further from second, more 442 Qulity of Life Reserch. Vol

11 Cndin-French, Germn nd UK versions of the CHQ comprehensive process using the protocol developed for the Cndin-French (nd other) version. Thus, second pnel of trnsltors (see cknowledgments) hs been ssembled to provide severl new forwrd versions. Once these versions hve been reconciled into single instrument, the second developmentl version will be piloted in severl new studies. The rigorous psychometric evlution s discussed in this pper will be repeted for the second version. The two developmentl versions will then be re-evluted. A finl recommendtion will be mde pending the outcome of this work. The overll results observed for the Cndin- French developmentl version re prticulrly encourging given the reltively smll smple size of the French spekers (n = 16). As reported erlier, the stndrd error is clculted by the smple size. A smller smple results in higher stndrd error. The smllest smple size ws observed for the Frenchspeking smple; conversely the highest stndrd error ws observed for this group (SE = 0.25). Thus, in the item scling tests for this smple, the item correltions hd to be somewht higher thn those chieved for other smples in order to be counted s success. Bsed on the results obtined for the Cndin- French version of the CHQ-PF50 in the fesibility study of the CCCSCP the form will be used in the lrger ntionl study. The ntionl study will lso be expnded to include nother comprble functionl instrument, the Helth Utilities Index Mrk 2 (HUI2) nd Mrk 3 (HUI3), 57 which will provide n opportunity to compre two different pproches to instrument construction nd scoring. In the UK, efforts re under wy to evlute the pplicbility of the Anglicized version further nd to collect country-specific normtive dt which will ssist in the interprettion of CHQ helth scles scores in tht country. Of note is the bsence of floor effects observed cross ll the smples. This my be n rtefct of the smples used in the pilot trnsltion projects. Few of the smples included children with moderte to high levels of morbidity. However, these findings re supported by other published evidence for children with epilepsy 3 (0% cross ll scles with the exception of 6% for role physicl nd 3% for prentl time impct nd prentl emotionl impct) nd end-stge renl filure 6 (0% cross ll scles; dt vilble from the uthor). In summry, the results chieved for the Germn, UK nd Cndin-French developmentl versions of the 50 item prent-completed CHQ (CHQ-PF50) nd the use of the Americn-English CHQ mong Englishspeking Cndins re robust enough to recommend their use in subsequent investigtions tht will llow for further psychometric evlutions, the collection of normtive dt nd the development of scoring nd interprettion guidelines. The empiricl results obtined in these projects underscore the vlue of using stringent protocols to develop conceptully robust trnsltions. As with ny instrument, vlidtion is n itertive process. The next step is to evlute the psychometric properties of these developmentl versions cross n rry of child chronic condition groups nd schoolbsed smples. Some hve rgued tht it is methodologiclly nd conceptully too chllenging to dequtely ssess the physicl nd psychosocil well-being of children nd dolescents nd their fmilies dequtely. Recent dvnces in mesurement nd the explosion of interntionl interest in mesuring children s helthrelted qulity of life, however, underscore the importnce of developing well-grounded nd wellvlidted instruments. Encourging their inclusion in interntionl reserch efforts prior to widespred dissemintion nd dopting rigorous methods for trnsltion nd subsequent evlution will gretly fcilitte efforts to understnd the helth nd wellbeing of children nd dolescents nd their fmilies better. Notes The preliminry item scling results for the Germn nd Cndin French versions of the CHQ were presented t the First nd Second Annul Meetings of the Interntionl Society for Qulity of Life Reserch Brussels, Belgium 1994 nd Montrel, Cnd, 1995, respectively. Acknowledgements This work ws supported s n internlly funded Helth Institute project. The principl uthor wishes to thnk ptients nd collegues from the following institutions. In the USA, Mrk Kosinski, Rebecc Voris nd Wendy Hrris, The Helth Institute, New Englnd Medicl Center, Boston, MA. In Cnd, Lori Gibbons, Lbortory Centre for Disese Control, Helth Cnd, Ottw; Mru Brrer, The Hospitl for Sick Children, Toronto nd trnsltors: Nicole Abetz, Andrée Christen, Bernrd Deschenes, Id Lngevin nd Pierrot Lmbert. In Germny, Professor Dr Lothr Schmidt, Heike Fröhling, Universitt Trier, Fchbereich Qulity of Life Reserch. Vol

12 J. M. Lndgrf et l. 1-Psychologie, Trier, H.C. Steinhusen, Deprtment of Child nd Adolescent Psychitry, University of Zurich, Switzerlnd nd Professor Dr Petr Wrschburger, Universitt Bremen, Zentrum fur Rehbilittionsforschung, Bremen. In the UK, Fion Vn, Dvid Crgg nd Mrtin Rolnd, Rusholme Helth Centre, Deprtment of Generl Prctice, University of Mnchester. References 1. Lndgrf JM, Wre JE Jr, Schor E, Dvies AR, R-Roh K. Helth profiles in children with psychitric nd other medicl conditions. Pper presented t the Ninth World Congress of Psychitry, Rio de Jniero, Brsil, 6 12 June, Lndgrf JM, Wre JE Jr, Schor E, Dvies AR, R-Roh K. Comprison of helth sttus profiles for children with medicl conditions: preliminry psychometric nd clinicl results from the Children s Helth nd Qulity of Life Project. Pper presented t the Tenth Annul Meeting of the Assocition for Helth Services Reserch, Wshington, DC, June, Lndgrf JM, Abetz L, Wre JE, Jr. The CHQ: A User s Mnul. 1st edn. Boston, MA: The Helth Institute, New Englnd Medicl Center, Lndgrf JM, Abetz L. Influences of sociodemogrphic chrcteristics on prentl reports of children s physicl nd psychosocil well-being: erly experiences with the Child Helth Questionnire (CHQ-PF50), In: Drotr D, ed. Qulity of Life Assessment in Children. Lwrence Erlbum, Lndgrf JM, Abetz L. Functionl sttus nd well-being of children representing three culturl groups: initil selfreports using the CHQ-CF87. J Psychol Helth, 1977; 12(6): Kurtin P, Lndgrf JM, Abetz L. Ptient-bsed helth sttus mesurements in peditric dilysis: expnding the ssessment of outcomes. Am J Kidney Dis 1994; 24(2): Powers P, Abetz L, Lndgrf JM. Adolescents with cystic fibrosis: mother, fther nd child reports of helth. Poster presenttion t the 104th Annul Convention of the Americn Psychologicl Assocition, Toronto, Cnd, August Lndgrf JM, Abetz LN, DeNrdo BA, Tucker LB. Clinicl vlidity of the Child Helth Questionnire- Prent Form in children with rheumtoid rthritis. Poster presenttion t the 1995 Ntionl Scientific Meeting of the Americn College of Rheumtology, Sn Frncisco, CA, October Wre JE, Keller SD, Gndek B et l. Evluting trnsltions of helth sttus questionnires: methods from the IQOLA project. Int J Technol Assess Helth Cre 1995; 11(3): Wre JE, Gndek B, IQOLA Project Group. Evluting instruments used cross-ntionlly: IQOLA project methods. In: Spilker B, ed. Qulity of Life nd Phrmcoeconomics in Clinicl Trils, 2nd edn., EuroQol Group. EuroQol: new fcility for the mesurement of helth-relted qulity of life. Helth Policy 1990; 16: Aronson NK, Acqudro C., Alonso J et l. Interntionl Qulity of Life (IQOLA) project. Qul Life Res 1992; 1: Bullinger M, Anderson R, Cell D, Aronson N. Developing nd evluting cross-culturl instruments from minimum requirements to optiml models. Qul Life Res 1993; 2: Bullinger M. Ensuring interntionl equivlence of qulity of life mesures: problems nd pproches to solutions. In: Orley J, Kuyken W, eds. 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