Brief communicationtall什么意思
Is the standard SF-12Health Survey valid and equivalent for a Chine population?
Cindy L.K.Lam1,Eileen Y.Y.T1&Barbara Gandek2
1Family Medicine Unit,the University of Hong Kong,Hong Kong SAR(E-mail:clklam@hku.hk);2IQOLA Project,Health Asssment Lab,Boston,MA USA
Accepted in revid form15June2004
Abstract
英文培训Introduction:Chine is the world’s largest ethnic group but few health-related quality of life(HRQoL) measures have been tested on them.The aim of this study was to determine if the standard SF-12was valid and equivalent for a Chine population.Methods:The SF-36data of2410Chine adults randomly lected from the general population of Hong Kong(HK)were analyd.The Chine(HK)specific SF-12 items and scoring algorithm were derived from the HK Chine population data by multiple regressions. The SF-36PCS and MCS scores were ud as criteria to asss the content and criterion validity of the SF-12.The standard and Chine(HK)specific SF-12PCS and MCS scores were compar
ed for equivalence. Results:The standard SF-12explained82%and89%of the variance of the SF-36PCS and MCS scores, respectively,and the effect size differences between the standard SF-36and SF-12scores were less than0.3. Six of the Chine(HK)specific SF-12items were different from tho of the standard SF-12,but the effect size differences between the Chine(HK)specific and standard SF-12scores were mostly less than0.3. Conclusions:The standard SF-12was valid and equivalent for the Chine,which would enable more Chine to be included in clinical trials that measure HRQoL.
Key words:Health-related quality of life,SF-12,Chine,Validity,Equivalence
Introduction
在线翻译汉译英
Chine make up nearly a quarter of the world’s population.They should be included in global and cross-cultural clinical trials but this is often not possible in studies that measure health-related quality of life(HRQoL)becau of language and cultural barriers.Most HRQoL measures are in English and originate from the Western culture,so they need to be translated and validated before they can be applied to the Chine.The Chine (Hong Kong)translation of the MOS36-item Short Form Health Survey(SF-36)and its physical and mental health summary(PCS and MCS) Scales have been shown
to be valid and equivalent for the Chine[1–5],but the length of the SF-36 limits its acceptability in some clinical trials that need to measure a number of outcomes.The standard SF-12Health Survey(SF-12),an abbre-viated form of the SF-36that yields the PCS and MCS scores,is becoming a popular HRQoL measure in clinical trials becau it can be com-pleted in a few minutes[6,7].
The items and scoring algorithm of the standard SF-12were derived from data of a US general population survey in1990[6–8].The standard SF-12PCS and MCS scores are norm-bad on the US general population who mean is50and standard deviation(SD)is10[6,9].The12items include two from each of the physical functioning, role-physical,role-emotional and mental health scales and one item from each of the bodily pain, general health,vitality and social functioning scales of the SF-36.The items were lected by multiple regressions in order to explain the largest proportion of the total variance in the SF-36PCS
Qual Life Res(2005)14:539–547ÓSpringer2005
and MCS scores.The respon to each item is weighted parately by the PCS and MCS regres-sion coefficient and then summated to give the standard SF-12PCS and MCS scores,respectively.
A small number and weighting of items may make a HRQoL measure more culture-nsitive [10,11].
All previous studies on the validity and equivalence of the standard SF-12were carried out in Caucasian populations[8,12].There was very little data from any Chine or Asian population who cultures are quite different from tho of the West.The rank orders by item mean of three(PF9, GH3and RE3)SF-36items were found to be different between the HK Chine and US popu-lations[1].Although the differential item func-tioning(DIF)of a few items did not affect the validity of the SF-36Scales that summated all the items without weighting[1,13],they may have an effect on the validity and equivalence of the much shorter standard SF-12.
The aim of this study was to determine if the standard SF-12was valid and equivalent for the Chine population of Hong Kong,or whether a Chine(HK)specific SF-12was needed.The standard SF-12is valid if it really measures the SF-36PCS and MCS scores,which are what it pur-ports to measure.The lected items should be reprentative and adequate in explaining the SF-36PCS and MCS scores(content validity),and the SF-12should give similar PCS and MCS scores as the SF-36(criterion validity).The standard SF-12 is equivalent if no more than three of the12items lected specifically from the Chine(HK)popu-lation were different from tho of the standard SF-12,as that found in other countries(item equivalence)[8];and if there is no important dif-ference between the results of the Chine(HK) specific and standard scoring algorithms(mea-surement equivalence)[8,14,15].
Methods
Data of2410Chine adults randomly lected from the general population of Hong Kong that were collected in the Chine(Hong Kong)SF-36 norming survey in1998were ud for analysis in this study.The detailed sampling and data collec-tion methods have been described in previous pa-pers[16,17].All subjects answered the Chine (Hong Kong)translation of the SF-36and a structured questionnaire on sociodemographic data.Each subject was also asked to indicate whether he/she had ever been diagnod by a doctor to have hypertension,diabetes mellitus, heart dia,stroke,chronic pulmonary dia, chronic joint dia,psychological illness or any other chronic dia.A subject was classified as not having any chronic dia if the respons to the chronic dia questions were all negative. Table1shows that the sociodemographic charac-teristics of the subjects were similar to tho of the general adult population in Hong Kong[18].The sample was comparable to the US population sample[19]from which the standard SF-12was derived in mean age(42.9vs.43.6years)and x distribution(47.8%vs.48%males).
The Chine(HK)specific SF-12items were lected by multiple regressions of the Chine (HK)specific SF-36PCS and MCS scores derived from the HK Chine adult population[3],bad on the criteria of the International Quality of Life Asssment(IQOLA)Project for cross-cultural adaptatio
n of the SF-12[8].The Chine(HK) specific PCS and MCS regression constants and coefficients for each item respon were obtained by regressing the Chine(HK)specific SF-36PCS and MCS scores on the Chine(HK)specific item scores.The SAS programme was ud for the multiple regressions analys.The SPSS Pro-gramme for Windows10.0(SPSS Inc.Chicago,IL, USA)was ud for all other data analys.
The standard SF-12PCS and MCS scores were calculated by the standard algorithm described in the SF-12Manual[6].The Chine(HK)specific and standard mean SF-12PCS and MCS scores were determined for all subjects and by lf-re-ported chronic dia groups.
Content validity was assd by the proportion of total variance of the SF-36PCS and MCS scores explained by the SF-12PCS and MCS,and P90%was the expected standard[6,8].It was further assd by Pearson correlations between the SF-12and SF-36PCS and MCS scores and the expected standard was P0.9[6,8].Effect size dif-ference between corresponding SF-12and SF-36 PCS and MCS scores was ud to determine if the SF-12gave similar or different results from tho of the SF-36(Criterion validity).Effect size dif-ference between the SF-36and SF-12scores was
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calculated by dividing their difference by the standard deviation(SD)of the SF-36summary score.
Measurement equivalence between the standard and Chine(HK)specific SF-12wasfirst assd by Pearson correlations(expected standard P0.9) and then the effect size differences between the standard and Chine(HK)specific scores.The effect size difference was calculated by dividing the difference between the corresponding SF-12 scores by the SD of the Chine(HK)specific SF-12score.The standard and Chine(HK)SF-12 scores were also compared by chronic dia groups in order to determine if they performed differently in different groups.A spectrum of chronic dias(Heart,chronic pulmonary,psy-chological and chronic joint)that are known to affect HRQoL were ud as tracer conditions[20]. There is no connsus on what the minimally important difference(MID)in HRQoL scores should be.Kazis et al.showed that the effect size changes in scores measured by the Arthritis Im-pact Measurement Scale were mostly between0.3 and0.5in the treatment group[21];and Wyrwich showed that the MID of the Chronic Heart Failure Questionnaire scores corresponded to effect size changes of0.34–0.37[22].We therefore adopted Cohen’s moderate effect size of0.3–0.5as the MID in this study[23,24].
Results
The Chine(HK)specific SF-12PCS and MCS scales
First forward stepwi regressions of the Chine (HK)specific SF-36PCS and MCS scores on the SF-36items lected two items each from the physical functioning(PF1,PF8)and mental health (MH3,MH4)scales,and one item each from the role-physical(RP3),bodily pain(BP1),social functioning(SF1)and role-emotional(RE3) scales.The cond forward stepwi regressions, with the general health item(GH1)and the above items forced into the model,lected the remaining items(RP2,VT4and RE1)that explained the greatest variance of the HK Chine specific SF-36 PCS and MCS scores.It is an IQOLA criterion that GH1should be included in all versions of SF-12becau it is an item common to many HRQoL measures[8].Table2shows the Chine(HK) specific SF-12items,in comparison with the standard SF-12items.The items that were differ-ent are shown in bold.The numbers in brackets correspond to the question numbers in the SF-36 Health Survey.
Table3shows the regression coefficients of the Chine(HK)specific SF-12items and tho of the
Table1.Sociodemographic characteristics of study sample compared with the Hong Kong general population
Sample
N=2410Hong Kong general adult population a N=5,333,610女同性恋 英语
Mean age(years)42.942.3
Age group(years)
18–4456.7%58.6%
45–6423.7%27.4%
65or above15.3%14.0%
Refud to answer 4.2%0%
Male47.8%48.3%
全国四六级报名Female52.2%51.7%
Marital status
Now married58.0%59.4%
Never married33.8%31.9%
Widow/widower 5.8% 6.0%
Divorced/parated 1.3% 2.7%
Refud to answer 1.1%0%
Educational level
No schooling 6.9%8.4%
Primary22.3%20.5%
Secondary52.2%54.6%
Tertiary17.8%16.4%
Refud to answer0.9%0%
Social class by occupation
Managers and
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administrators
N.A.10.7%b
Professional 3.1% 5.5%
Associate professional14.7%15.0%
Skilled worker35.4%33.5%c
Semi-skilled worker24.6%15.0%d
Non-skilled worker14.4%19.8%e
Refud to answer7.7%0%
a Data from the Hong Kong2001Population Census.
休假英文
b This occupation category is not applicable to the social class
by occupation classification.
c Craft workers,plant an
d machin
e operators and asmblers.
d Servic
e and shop sales workers.
e Workers in elementary occupation,agriculture andfishery,
and unclassified.
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standard SF-12items,derived from the HK gen-eral Chine population sample.The regression coefficient of the best respon choice of each item is not shown becau it is the indicator variable. The Chine(HK)specific PCS and MCS regres-sion coefficients of each item respon were ud s
eparately to weight each item respon for the calculation of the PCS and MCS scores.The weight for the best respon choice of each item is zero.Summation of the relevant Chine(HK) specific regression constant and item respon PCS and MCS regression coefficients would give the Chine(HK)specific SF-12PCS and MCS scores, respectively.
Content and criterion validity of the SF-12PCS and MCS
The R2in Table3indicates the proportion of total variance in the SF-36PCS or MCS score that was explained by the corresponding SF-12summary score.The standard SF-12PCS and MCS ex-plained82%and89%of the total variances of the standard SF-36PCS and MCS,respectively.The Chine(HK)specific SF-12PCS and MCS ex-plained88%and90%of the total variances of the Chine(HK)specific SF-36PCS and MCS, respectively.
Table4shows the correlations between the SF-12and SF-36PCS and MCS scores.The correla-tions between the corresponding SF-36and SF-12 summary scores all reached the expected standard of0.9.
The mean and standard deviation(SD)of the Chine(HK)specific and standard SF12and SF-36PCS and MCS scores of the whole sample and by lf-reported chronic dia groups are shown in Tabl
e5.The effect size differences(effect size1) between corresponding SF-36and SF-12scores were all less than0.3.
Measurement equivalence between the chine (HK)specific and standard SF-12
As shown in Table4,the correlations between the corresponding standard and Chine(HK)specific SF-12PCS and MCS scores were just short of0.9. The standard and Chine(HK)specific SF-12 scores are compared in Table5.The mean stan-dard SF-12PCS and MCS for the overall HK Chine population were50.2and48.4,respec-tively,which were similar to the US general pop-ulation means of50.The Chine(HK)specific and standard SF-12detected similar significant differences between each chronic dia group and the‘no chronic dia’group.The largest difference between the Chine(HK)specific and standard SF-12scoring algorithms was the PCS score of people reporting heart dias,with an effect size of0.36.
Discussion
The standard SF-12did not satisfy the criterion on item equivalence for the Chine population in
Table2.The Chine(HK)specific SF-12items compared with the standard SF-12items
SF-36scales Chine(HK)specific SF-12items Standard SF-12items
Physical functioning(PF)PF1(3a)Vigorous activities PF2(3b)Moderate activities
PF8(3h)Walking veral blocks PF4(3d)Climbing veralflights Role-physical(RP)RP2(4b)Accomplished less RP2(4b)Accomplished less
RP3(4c)Limited in kind of work RP3(4c)Limited in kind of work
Bodily pain(BP)BP1(7)How much bodily pain
have you had BP2(8)how much did pain interfered with work
General health(GH)GH1(1)Your GH1(1)Your
Vitality(VT)VT4(9i)Did you feel tired VT2(9e)Did you have a lot of energy
Social functioning(SF)SF1(6)Extent social activities
was interfered SF2(10)How much time social activities was interfered
Role-emotional(RE)RE1(5a)Cut down time on work RE2(5b)Accomplish less
RE3(5c)Didn’t do work as carefully RE3(5c)Didn’t do work as carefully Mental health(MH)MH3(9d)Felt calm&peaceful MH3(9d)Felt calm&peaceful
MH4(9f)Felt downhearted&blue MH4(9f)Felt downhearted&blue 542
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Table3.Forward stepwi regressions of SF-36PCS and MCS scores on the SF-12item respons
卖炭翁翻译
Item_Respon scores PCS regression coefficients MCS regression coefficients
Chine(HK)specific Standard Chine(HK)specific Standard
中口考试时间PF1_1)8.042639– 2.795780–
PF1_2)3.641426– 1.121187–
PF2_1–)6.609693– 3.461042
PF2_2–)2.782074– 1.314947
PF4_1–)6.269240– 2.586866
PF4_2–)2.427698–0.752688
PF8_1)16.203705–7.818665–
PF8_2)7.963922– 3.164988–
RP2_1)4.343623)4.390177)0.705448 1.022170
RP3_1)5.044296)5.0474760.256528 1.278842
BP1_1)17.012005– 3.635025–
BP1_2.2)12.695771– 2.349628–
BP1_3.1)9.002881– 1.931547–
BP1_4.2)6.377284– 1.507313–
BP1_5.4)3.772960–0.652800–
BP2_1–)12.257268– 2.208989
BP2_2–)10.594807– 2.500285
BP2_3–)7.912197– 1.500170
BP2_4–)4.970550– 1.033358
GH1_1)8.704344)8.042873)0.8411670.184282
GH1_2)5.382641)4.663071)1.133139)0.389631
GH1_3.4)3.230279)2.706827)0.660725)0.349572
GH1_4.4)1.936141)1.671905)0.7950150.330309铜版纸英文
VT2_1–)1.704222–)7.001461
VT2_2–)1.355533–)5.031671
VT2_3–)0.262164–)4.012001
VT2_4–)0.150904–)2.677302
VT2_5–0.150005–)1.396547
VT4_1)2.301203–)6.694192–
VT4_2)1.673615–)6.555417–
VT4_3)1.217702–)4.965228–
VT4_4)0.849186–)2.403254–
VT4_5)0.495087–)1.041427–
SF1_1 2.955278–)14.617923–
SF1_2 1.116653–)12.142296–
SF1_3 1.433979–)7.841254–
SF1_40.861761–)4.676580–
SF2_1–0.286656–)8.236227
SF2_2–)0.189464–)6.857423
SF2_3–0.193895–)5.284785
SF2_4–0.482796–)3.301877
RE1_1 2.468990–)6.099051–
RE2_1– 2.747609–)6.981024
RE3_1 1.642657 2.143392)5.120612)5.946570
MH3_10.486081 2.865890)8.496928)8.255860
MH3_2 1.644377 3.500893)8.257450)6.883770
MH3_30.696675 2.694178)6.255882)5.404594
MH3_40.864621 2.333822)4.238056)3.439909
MH3_50.774435 1.609226)2.544268)1.943186
MH4_10.851938 4.534201)12.868018)15.794343
MH4_2)0.119061 2.494064)9.187208)12.925241
MH4_3 1.319095 2.212045)7.247869)9.157472
