Elegance Ting Pui Lam, Cindy Lo Kuen Lam, Ching Lung
Lai, Man Fung Yuen,
Department of Medicine, The
University of Hong Kong, Hong Kong, China
Daniel Yee Tak Fong,
Department of Nursing Studies, The University of Hong Kong, Hong Kong,
All authors participated in the design of the study; Lam ETP, Lai CL and
Yuen MF collected the data; Lam ETP, Lam CLK and Fong DYT were involved
in data analysis and interpretation; Lam ETP and Lam CLK drafted the
manuscript; All authors read and approved the final manuscript.
Small Project Grant from the Committee of Research and Conference Grant,
CRCG project, No. 10207293, the University of Hong Kong and the Health
and Health Service Research Fund, HHSRF project, No. 05060741, Food and
Health Bureau, Government of Hong Kong Special Administration Region,
Correspondence to: Elegance Ting Pui Lam,
Family Medicine Unit, Department of Medicine, The University of Hong
Kong, 3/F, Ap Lei Chau Clinic, 161 Main Street, Ap Lei Chau, Hong Kong,
February 3, 2009
May 25, 2009
June 1, 2009
July 14, 2009
To test the psychometric properties of a Chinese [(Hong
Kong) HK] translation of the chronic liver disease questionnaire (CLDQ).
A Chinese (HK) translation of the CLDQ was developed by
iterative translation and cognitive debriefing. It was then administered
to 72 uncomplicated and 78 complicated chronic hepatitis B (CHB)
patients in Hong Kong together with a structured questionnaire on
service utilization, and the Chinese (HK) SF-36 Health Survey Version 2
Scaling success was
80% for all but three items. A new factor assessing sleep was found and
items of two (Fatigue and Systemic Symptoms) subscales tended to load on
the same factor. Internal consistency and test-retest reliabilities
ranged from 0.58-0.90 for different subscales. Construct validity was
confirmed by the expected correlations between the SF-36v2 Health Survey
and CLDQ scores. Mean scores of CLDQ were significantly lower in
complicated compared with uncomplicated CHB, supporting sensitivity in
detecting differences between groups.
The Chinese (HK) CLDQ is valid, reliable and sensitive
for patients with CHB. Some modifications to the scaling structure might
further improve its psychometric properties.
© 2009 The WJG Press and Baishideng. All rights reserved.
Chronic liver disease; Health-related quality of life;
Hepatitis B; Southern Chinese; Validity
Edmund J Bini, Professor, VA New York Harbor Healthcare System, Division
of Gastroenterology (111D), 423 East 23rd Street, New York 10010, United
ETP, Lam CLK, Lai CL, Yuen MF, Fong DYT. Psychometrics of the chronic
liver disease questionnaire for Southern Chinese patients with chronic
hepatitis B virus infection. World J Gastroenterol 2009; 15(26):
3288-3297 Available from: URL: http://www.wjgnet.com/1007-9327/15/3288.asp
Chronic hepatitis B (CHB) virus infection remains a major
global health problem. It is estimated that 350 million people worldwide
are chronically infected, of whom one third (120 million) are Chinese.
The prevalence is higher in southern China (> 10%) than Northern China
(6%-10%). Up to 25% of patients may die from CHB
complications, such as cirrhosis-related complications or hepatocellular
carcinoma (HCC), posing a threat to both mental and physical health,
leading to impairment of health-related quality of life (HRQOL).
HRQOL has become an important outcome measure in clinical
and health policy settings in the last two decades. Disease-specific
measures are often needed to complement generic measures to give a more
comprehensive evaluation of the HRQOL of patients with specific
diseases. Several HRQOL measures have been developed specifically for
chronic liver disease (CLD), such as the Chronic Liver Disease
Questionnaire (CLDQ), the Hepatitis Quality of Life (HQLQ),
the Liver Disease Quality of Life and the Liver Disease
Symptom Index (LDSI). The CLDQ developed by Younossi et
al was the first and is the most widely used. The
other liver disease-specific HRQOL measures are not commonly used
because they are either too long, or the validity data are limited[4-8].
The CLDQ consists of 29 items which are grouped into 6
subscales: abdominal symptoms (AS), fatigue (FA), systemic symptoms
(SS), activity (AC), emotional function (EF) and worry (WO). It is
applicable to all types of liver diseases including CHB. It has been
shown to have adequate internal reliability, validity and sensitivity.
Test-retest reliability was more variable with intra-class correlation (ICC)
ranging from 0.23 to 0.72 for different subscales.
Previous studies showed that the CLDQ is more responsive than a generic
measure to detect a change in patients with CLD[3,9]. It has
been translated and validated in different languages[9-13],
supporting its potential for cross-cultural adaptation. However, most of
the psychometric data of the CLDQ have been derived from patients with
hepatitis C virus (HCV) infection and Western populations. There are few
data on its applicability for Southern Chinese CHB patients despite the
fact that China has the world’s largest population suffering from CLD.
Recently, the CLDQ has been translated into Mandarin
Chinese but this Chinese (Mainland) version may not be applicable to
Southern Chinese who speak Cantonese, a dialect that has significant
differences in the usage of words and terms from Mandarin. In addition,
information on the validity, reliability and other psychometric
properties of the Chinese (Mainland) CLDQ version is limited. The aim of
this study was to test the psychometric properties of a Chinese [Hong
Kong (HK)] translation of the CLDQ for Southern Chinese CHB patients.
This would enable the evaluation of the impact of CHB infection and
assess the effect of anti-viral drug treatments on HRQOL in the world’s
largest population of CHB patients.
The objectives of this study were: (1) To develop a
Chinese (HK) CLDQ that is semantically equivalent to the original; (2)
To test the scaling assumptions and factor structure of the Chinese (HK)
CLDQ; (3) To assess the psychometric properties in terms of reliability,
construct validity, and sensitivity of the Chinese (HK) CLDQ; (4) To
determine whether any modification of the CLDQ can improve its
psychometric properties for Southern Chinese CHB patients.
MATERIALS AND METHODS
This research project was approved by the Institutional
Review Board of the University of Hong Kong/Hospital Authority Hong Kong
West Cluster (IRB reference No., UW 06-089 T/1114 and trial registration
Development of the Chinese (HK) CLDQ
The Chinese (HK) translation of the CLDQ was developed by
iterative translations, expert panel review and cognitive debriefing, as
recommended guidelines by experts[14,15]. The original CLDQ
was translated into Chinese by two independent professional translators.
Reconciliation of the forward translations into a single forward
translation was carried out by a bilingual expert in HRQOL measures (Lam
CLK) and the translators. The reconciled Chinese translation was
back-translated into English by another professional translator. The
back translation was reviewed by the original author and the bilingual
expert to identify any non-equivalence in the Chinese translation, which
was then revised. The first draft of the Chinese (HK) CLDQ was evaluated
by cognitive debriefing interviews with six Southern Chinese patients
with CHB infection and further revision was made to ensure item clarity
and equivalence to become the final Chinese (HK) CLDQ (used in this
study on psychometrics properties).
Patients with complicated CHB were recruited from
outpatient hepatitis clinics of a regional hospital and patients with
uncomplicated CHB were randomly selected from the computerized registers
of three public primary care clinics serving over 100 000 people in one
of five regions in Hong Kong. Patients aged 18 years or older who were
hepatitis B surface antigen-positive for more than six months were
included in the study. Patients were excluded if they could not
communicate in Cantonese; had cognitive impairment shown by the
patient’s inability to understand the study to give consent; were
co-infected with HIV, HCV or hepatitis D virus; had undergone liver
transplantation or had end-stage non-hepatitis B-related illnesses; were
currently taking excessive alcohol (> 30 U/wk) or illegal drugs; or
refused to give consent. Each patient completed the Chinese (HK) CLDQ,
the Chinese (HK) SF-36v2 Health Survey and a structured questionnaire on
morbidity and socio-demographics, administered by a trained interviewer.
Each patient was asked if he/she had ever been diagnosed by a registered
practitioner for more than four weeks to have hypertension, diabetes
mellitus, heart disease, stroke, chronic lung disease, arthritis,
psychological illness (i.e. depression, anxiety, neurasthenia or
psychosis) or any other chronic diseases. Chronic co-morbidity was
measured by the total number of diseases (summation of positive
responses to the questions) and the presence of a specific diagnosis.
Clinical data related to the CHB infection including Child’s staging for
patients with cirrhosis and the biomarkers of liver disease (alanine
aminotransferase, aspartate aminotransferase,
and total bilirubin) in each patient were retrieved from medical
records. Socio-demographic data including age, gender, education,
marital status, occupation, household income and family history of liver
disease were also collected.
The Chinese (HK) CLDQ was re-administered to the 46
subjects with uncomplicated CHB, whose condition was expected to be
stable, by telephone two weeks from the first administration, in order
to assess the test-retest reliability of the Chinese (HK) CLDQ. Sixty
one percent of the repeat interviews were carried out by the same
The Chinese (HK) CLDQ consists of 29 items measuring six
subscales as described above. Each item is rated on a 7-point (1 = all
of the time to 7 = none of the time) Likert scale. Scores for each of
the six domains are calculated by the mean of the item scores within the
subscale. A summary score is calculated by the mean of all subscale
scores. The scores range from 1 to 7 with a higher score indicating
The Chinese (HK) SF-36v2 Health Survey is a generic HRQOL
measure that has been translated, validated and normed on the general
Chinese population in Hong Kong[16,17]. It measures eight
domains of HRQOL on physical functioning (PF), role-physical (RP),
bodily pain (BP), general health (GH), vitality (VT), social functioning
(SF), role-motional (RE) and mental health (MH). Summations of item
scores of the same domain give the domain scores, which are transformed
into a range from 0 to 100. A higher score indicates better HRQOL. The
eight domain scores are summarized to form the physical component (PCS)
and mental component (MCS) summary scores.
All data analysis was carried out in SPSS for Windows
15.0. Statistical significant levels were set at P values less
The CLDQ item and subscale scores were calculated and
tested against the following scaling assumptions: (1) Items should be
substantially linearly correlated to the hypothesized subscale score
with a coefficient of 0.4 or above by Spearman rank correlation test, to
show the item is a significant indicator for the subscale concept. (2)
An item should have a stronger correlation with its hypothesized
subscale than other subscales indicating scaling success.
This is a test of item discriminant validity. The difference between
correlations is statistically significant if it is greater than two
standard errors (1 divided by the square root of sample size).
Exploratory factor analysis using principal components
with varimax rotation was performed to evaluate the factor structure of
the Chinese (HK) CLDQ. The criterion for factor extraction was an
eigenvalue greater than one. The highest factor loading was identified
for each item. The scree plot was also used to determine the number of
Construct validity was also tested by convergent validity
determined by Spearman correlations between corresponding CLDQ and
SF-36v2 Health Survey domain scores. It was hypothesized that moderate (r
= 0.4 to 0.7) to strong (r > 0.7) correlations should exist
between CLDQ FA and SF-36v2 VT; between CLDQ SS and SF-36v2 BP; between
CLDQ AC and SF-36v2 PF, RP and RE; and between CLDQ EF and SF-36v2 MH
The mean CLDQ scores were compared between two CHB
patient groups, and the difference was tested by independent t to
evaluate its sensitivity in detecting a difference between patients with
complicated and uncomplicated infections. The sensitivity of the CLDQ
was also assessed by the effect size (difference between group mean
scores/overall standard deviation). According to Cohen,
effect sizes of 0.3, 0.5 and 0.8 were considered small, medium and large
differences, respectively. An effect size of less than 0.3 was
considered not significant.
Different methods were used to assess reliability,
including internal consistency and test-retest reliability. Internal
consistency was measured by Cronbach’s
which is a measure of the extent to which items in a questionnaire are
homogeneous (correlated) in supporting the same concept.
Test-retest reliability refers to the stability of an instrument over
time, which was measured by the intra-class correlation
(ICC) between the two-week test-retest results. Reliability coefficients
0.7 and 0.9 are usually expected for group comparisons and individual
Translational equivalence of the Chinese (HK) CLDQ
All items except item 11 (level of energy) were found to
be understood by 6 patients. Three out of six patients did not
understand item 11. Five patients (83%) interpreted the meaning of all
except four items (11, 13, 19 and 28) correctly. Four out of six
patients misinterpreted the meaning of item 11 with three interpreting
it as decreased physical strength. Two patients (33.3%) had difficulty
in differentiating the meaning of “sleepy” and “drowsy”; and did not
seem to have interpreted the words “mood swings” (item 19). Two out of
six patients did not include the meaning of “worried about never feeling
better” (item 28) in their interpretation. The Chinese (HK) translation
was revised based on the results of cognitive debriefing and the revised
questionnaire was then field tested on 23 CHB patients before this
study. The final Chinese (HK) CLDQ was formed and its back-translation
is shown in the appendix.
One hundred and eighty four CHB patients were identified;
6 patients were excluded (3 had hepatitis B infection less than 6 mo, 2
had communication problems and 1 had co-infection with HCV) and 28
patients refused to participate in this study. One hundred and fifty
Chinese adults consisting of 72 uncomplicated (normal liver function
defined as liver enzymes persistently within the normal range and
without any history of cirrhosis or HCC) and 78 complicated (cirrhosis
or HCC) completed the study, giving a response rate of 84.3% (150/178).
Table 1 shows their characteristics, overall and by disease severity
groups. There were 8 patients in the complicated CHB group who had HCC
without any cirrhosis and had normal liver function. There were no
statistical differences in demographics between the uncomplicated and
complicated CHB groups, except age and sex (P < 0.001).
Complicated CHB patients were older and there were more men than those
in the uncomplicated group which was expected because CHB complications
were more common in men than in women and the median age for the
development of complications was 57.2 years[22,23].
Table 2 shows the distribution of the Chinese (HK) CLDQ
and SF-36v2 scores. There was practically no floor effect but there were
significant ceiling effects in the Chinese (HK) CLDQ AS, AC and WO
subscales, more so in the uncomplicated than the complicated group.
Significant ceiling effects were also found in most SF-36v2 Health
Survey scales. Sub-group analysis showed that the mean Chinese (HK) CLDQ
scores were significantly lower in the complicated group than the
uncomplicated group in all subscale and overall scores.
Figure 1 compares the distribution of the Chinese (HK) CLDQ scores with those from other countries. The distribution pattern of
the Chinese (HK) CLDQ subscale scores was very similar to those of other
countries[3,9,11,13], except Italy, supporting
cross-cultural conceptual equivalence.
Table 3 shows the mean item scores and standard deviation
of the 29 CLDQ items grouped under their hypothesized subscales. All
correlations between items and their hypothesized subscales score
exceeded the standard of 0.4.
All but six items had a higher correlation with its
hypothesized subscale than other subscales, i.e. 100% scaling success.
Four items of the SS subscale and two items of the AC subscale
correlated more highly with some other subscales than their own. Scaling
success was the lowest in item 3 “bodily pain”, which correlated more
highly with four other subscales than with the SS subscale, with the
highest found for EF, but the differences were not statistically
significant. Items 6 “shortness of breath”, 23 “dry mouth”, 27
“itching”, 7 “not able to eat as much as you would like” and 9 “trouble
in lifting or carrying heavy objects” correlated higher with one to
three other subscales than its own, but the differences in the
correlations were not statistically significant.
The overall scaling success rate on discriminant validity
was 100% for four scales (AS, FA, EF and WO), but it was 73% for the AC
subscale and 64% for the SS subscale.
Table 4 illustrates the rotated factor loadings between
the 29 items and 6 factors with eigenvalue > 1. The six factors
explained 70.1% of total variance. The factor loadings of the items were
not entirely consistent with the scaling hypothesis. Items of the FA and
SS subscales, except bodily pain (item 3), decreased strength (item 8)
and decreased energy (item 11), seemed to load on the same factor
(factor 3). Two FA subscale items (8 “decreased energy” and 11
“decreased strength”) loaded more strongly on AC than its hypothesized
factor. A new factor (factor 6) was found with the highest loading from
two items assessing sleep (items 16 and 20). The items of EF, WO, AS and
AC subscales loaded nicely on their hypothesized factors.
Table 5 shows the correlations between the scores of the
CLDQ and SF-36v2 Health Survey. As hypothesized, moderate to strong
correlations were found between CLDQ FA and SF-36v2 VT scores; and
between CLDQ SS and the SF-36v2 BP scores. The CLDQ AC score correlated
significantly with all SF-36v2 Health Survey domain scores and the
strongest was found with the SF-36v2 RP and SF scores. The CLDQ EF score
correlated strongly not only with the SF-36v2 MH score but moderately
with the SF-36v2 VT, RE, RP and GH scores.
As shown in Table 2, the CLDQ overall and subscale mean
scores were all significantly higher in the uncomplicated than the
complicated CHB group. The effect sizes of the group differences in the
CLDQ scores all exceeded 0.4 (range 0.4-0.6). Only three of the eight
SF-36v2 domain scores (PF, RP and SF) and the PCS score detected a
significant difference between the uncomplicated and the complicated
groups. However, the greatest effect size difference between the two
groups was found in the SF-36v2 RP score.
Across all subscales, the Cronbach’s
coefficients of the internal consistency reliability were higher than
the recommended value of 0.7 (Table 5). ICC coefficients measuring the
two-week test-retest reliability exceeded 0.7 in all but the AS (0.58)
and AC (0.66) subscales. The reliability coefficients were comparable to
those of the SF-36v2 Health Survey.
Table 5 also shows that the correlations (range
0.50-0.87) between the CLDQ subscales were smaller than the subscale
internal reliability coefficients for all subscales, showing that each
subscale measures a distinct concept. The overall CLDQ scores correlated
strongly with all CLDQ subscale scores.
The mean scores of the CLDQ found in our population were
generally higher than those found in other countries. This might be the
result of a sampling difference, in that over half of our subjects had
uncomplicated CHB infection and most of the other studies included
patients with more serious diseases and patients with HCV who tend to
have more impairment in HRQOL than patients with CHB infection.
The other reason for a difference in the absolute HRQOL scores between
different populations is a difference in the sociocultural norms. A
comparison with the population norms of generic HRQOL measures such as
those of the SF-36 Health Survey will provide a more meaningful
interpretation on the impact of CHB on HRQOL between different
populations. Our study found that uncomplicated CHB patients had
significant impairment in the SF-36v2 RP, BP, SF and RE domains, and
complicated CHB patients had significantly lower SF-36v2 scores in six
domains (PF, RP, BP, GH, SF and RE) than the norms of the HK population
(Table 2)[25,26]. The findings suggested that CHB infection
affected HRQOL only modestly unless complications develop. Surprisingly,
there was no difference in the MH score between CHB patients and the HK
population norm. It was unlikely that a potentially lethal chronic
infection had no effect on mental health, the SF-36v2 Health Survey was
probably not sensitive enough to detect the difference.
The high ceiling effects in the AS, AC and WO subscales
in patients with uncomplicated CHB were expected since they were usually
asymptomatic. A pattern that was similar to that found in a Spanish
population. A high ceiling effect was also observed among
patients with complicated CHB which was unexpected, this was probably
because most of our subjects with complicated CHB were under anti-viral
treatment that might have improved their HRQOL, or perhaps some patients
had adjusted to their illnesses. On the whole, the CLDQ had a lower
ceiling effect than the SF-36v2 Health Survey, suggesting that this
disease-specific HRQOL measure would be more responsive than the generic
measure in detecting improvements with treatment, which needs to be
confirmed by prospective studies. The lack of floor effect indicates
that the Chinese (HK) CLDQ would be able to capture any deterioration in
patients’ QOL as the disease progresses.
The item-subscale correlations and factor analysis
results supported the scaling structure of the Chinese (HK) CLDQ in
general. However, the scaling success rates of items 3 (bodily pain), 23
(dry mouth) and 9 (trouble in lifting or carrying heavy objects) seemed
too low to be acceptable, raising the question whether they should be
grouped under other subscales than the originally hypothesized. It is
interesting to note that bodily pain correlated the most with the EF
subscale score and loaded the strongest on the EF factor (Table 4). It
is a common observation that emotional state has a strong influence on
pain perception and vice versa. Although the items on dry mouth
or trouble in lifting or carrying heavy objects correlated more strongly
with other subscales than their own, they should probably remain in the
hypothesized subscale because the differences in the item-subscale
correlations were not significant and the item-hypothesized subscale
correlations were greater than 0.4. Furthermore, the factor loading
results were not consistent with the results of the item-subscale
correlations. The item “dry mouth” correlated most strongly with WO
subscale score but the loading was the highest on the SS factor (0.48).
The item “trouble in lifting or carrying heavy objects” correlated
highest with the SS score but factor analysis showed that it loaded most
strongly on the factor of EF.
The factor structure of the Chinese (HK) CLDQ version was
almost identical to the original CLDQ in four subscales (EF, WO, AS and
AC). The new factor of Sleep found in our Chinese population was also
found in the Spanish, Italian and German population[9,10,27].
CHB patients may have sleep difficulties due to reasons other than
emotional problems, such as pain and other symptoms. The items of the FA
and SS subscales, except items 3, 8 and 11, loaded on one single factor
since they all measure symptoms. Items 8 and 11 of the FA subscale
loaded on the AC factor. Factor analysis with promax rotation was also
performed to cross-validate the factor structure obtained by the varimax
rotation, and it showed similar results with a new factor assessing
sleep and items of the FA subscale loaded mostly on the AC factor
instead of a separate factor.
An alternative scaling structure for the Chinese (HK)
CLDQ based on the factor loading results could be formed. Items 16
(difficulty in sleeping) and 20 (difficulty in falling asleep at night)
were grouped into a new Sleep subscale. Items 8 (decreased strength) and
11 (decreased energy) were grouped into the AC subscale. Items 2, 4 and
13 of the original FA subscale are grouped with items of the SS subscale
to form the new SS subscale. Item 3 (bodily pain), although loaded most
strongly and correlated the most with EF factor, remains in the SS
subscale because this has better face validity. The psychometric
properties of the revised Chinese (HK) CLDQ subscales with re-grouping
of the items are shown in
Table 6. It can be seen that the new subscale
structure greatly improves the scaling success rates of the SS and AC
items, although it reduces the success rate of the EF subscale slightly.
The new scaling structure also reduced the ceiling effects of the SS and
AC subscales. Further studies are needed to determine whether the
revised subscale structure will translate into better sensitivity and
responsiveness in clinical applications. Until such data are available,
the original subscale structure of the CLDQ is recommended to allow
better international comparability.
The expected correlations between the CLDQ and SF-36v2
Health Survey domains were observed confirming convergent construct
validity. The correlation with the SF-36v2 RE domain was higher in the
CLDQ EF than the AC subscale because conceptually the SF-36v2 RE
measures the effect of emotional problems on daily activities.
The CLDQ subscales of AS and WO address domains that are
not assessed by the generic measure (SF-36v2 Health Survey) and detected
significant differences between the two groups of CHB patients. There
were significant differences in the WO and EF subscales of the CLDQ
between the CHB groups although this was not found in most of the
mental-health related domains (RE, MH and MCS) of the SF-36v2 Health
Survey, suggesting that the Chinese (HK) CLDQ was more sensitive than
the generic measure in detecting the emotional impact of CHB. It is
worth noting that although more domains in the CLDQ showed a significant
difference between the complicated and uncomplicated CHB groups, the
largest effect size difference was found in the SF-36v2 RP domain
indicating that a disease-specific measure may not always be more
sensitive than a generic measure. The two types of HRQOL measures should
complement each other in the evaluation of the HRQOL of CHB patients.
Internal consistency and test-retest reliability were
acceptable for all subscales. Test-retest reliability (ICC) of the AS
subscale was relatively low (0.58) probably because these symptoms could
fluctuate from day to day and pain intensity might vary noticeably in a
relatively short period of time. Reliability of the CLDQ in our study
was generally higher than those found in other studies (0.46-0.95)[9,12].
The SS subscale had very good test-retest reliability (ICC 0.86) in our
population. The very low ICC (0.23) found in the US study was likely the
result of an inappropriately long retest interval of six months.
Our study administered the Chinese (HK) CLDQ using an
interviewer since our populations had a relatively low literacy level.
The performance of the instrument by self-completion will need to be
confirmed by further studies. The responsiveness of the Chinese (HK)
CLDQ in detecting changes with disease progression or anti-viral
treatment will also need to be determined.
The Chinese (HK) CLDQ was validated in content and
construct. It had satisfactory psychometric properties in terms of
factor structure, scaling assumption, construct validity, reliability
and sensitivity in Southern Chinese patients with CHB infection. It was
more sensitive than the SF-36v2 Health Survey in detecting the impact of
CHB on mental-health and symptom related HRQOL. The Chinese (HK) CLDQ
should be applicable to all Cantonese-speaking Chinese in HK and other
parts of Southern China. It is also likely to be applicable to the
majority of Chinese populations in Australia, North America, and Europe
who are mostly emigrants from HK. There was good equivalence in the
score distribution pattern across several cultures indicating that it
can be used as a cross-cultural HRQOL measure in multiethnic populations
or global studies. Some modifications of the scaling structure of the
CLDQ may improve its psychometric properties for CHB patients, which
need to be explored by further clinical studies.
Appendix: Back-translation of Chinese (HK)
|This questionnaire is designed
to find out how you have been feeling during the
last 2 wk.
||The purpose of this questionnaire is to
understand how you felt in the past 2 wk.
|You will be asked about you
symptoms related to your liver disease, how you
have been affected in doing activities, and how
your mood has been.
||The questions are about the symptoms
resulting from your liver illness and how these
symptoms affect your participation in
activities, and your emotions.
|Please complete all of
questions and select only one response for each
||Please answer all questions. You can only
choose one answer for each question.
|1 How much of the time during
the last 2 wk have you been troubled by a
feeling of abdominal bloating?
||1 In the past 2 wk, how much time you have
been bothered by your bloating problem?
|All of the time
||All the time
|Most of the time
||Most of the time
|A good bit of the time
|Some of the time
|A little of the time
||A Short Time
|Hardly any of the time
|None of the time
|2 How much of the time have you
been tired or fatigued during the last 2 wk?
||2 In the past 2 wk, how much time did you
feel tired or exhausted?
|3 How much of the time during
the last 2 wk have you experienced bodily pain?
||3 In the past 2 wk, how much time did your
|4 How often during the last 2
wk have you felt sleepy during the day?
||4 In the past 2 wk, how often did you feel
sleepy during the daytime?
|5 How much of the time during
the last 2 wk have you experienced abdominal
||5 In the past 2 wk, how much time did you
have abdominal pain?
|6 How much of the time during
the last 2 wk has shortness of breath been a
problem for you in your daily activities?
||6 In the past 2 wk, how much time were your
daily activities affected by your shortness of
|7 How much of the time during
the last 2 wk have you not been able to eat as
much as you would like?
||7 In the past 2 wk, how much time were you
unable to eat as much as you want?
|8 How much of the time in the
last 2 wk have you been bothered by having
||8 In the past 2 wk, how much time have you
been bothered by the decline in your physical
We thank Ms Fong Nga Po and Ms Cara Chan Yuen Yee for
their assistance in data collection and entry, and the staff of the
Division of Hepatobiliary/Pancreatic Surgery & Liver Transplantation and
Gastroenterology & Hepatology Specialist Outpatient Clinics, Queen Mary
Hospital for their help in patient recruitment.
Chronic hepatitis B (CHB) virus infection remains a
global problem and a public health threat. CHB patients may suffer or
die from liver-related complications, posing a threat to both mental and
physical health, leading to impairment of quality of life.
Health-related quality of life (HRQOL) outcomes should
supplement traditional clinical outcomes in the evaluation of the impact
and the effectiveness of treatment for patients with CHB infection.
Innovations and breakthroughs
The Chronic Liver Disease Questionnaire (CLDQ) had been
applied mainly to patients with hepatitis C virus infection in Western
countries. This study was the first to show that a Chinese (Hong Kong)
translation of the CLDQ was valid, reliable and sensitive for Southern
Chinese patients with CHB infection. The CLDQ can be applied to millions
of Southern Chinese CHB patients to evaluate their HRQOL. Some
modifications might further improve its validity, reliability and
The Chinese (Hong Kong) CLDQ can be used to evaluate the
impact of CHB virus infection and assess the effectiveness of anti-viral
drug treatments in Cantonese-speaking Southern Chinese. The CLDQ can be
used as a cross-cultural HRQOL measure in international studies that
include Southern Chinese.
CHB virus infection refers to those who are hepatitis B
surface antigen-positive for more than six months. Validity is defined
as the extent to which a test measures what it is intended to measure.
Reliability refers to the consistency or stability of the measurement
process across time, patients or observers.
The authors validated and tested the psychometric
properties of a Southern Chinese translation of the CLDQ and determined
that their questionnaire was valid, reliable, and sensitive for southern
Chinese patients with hepatitis B virus infection. The study was well
done and used appropriate methodology to validate and test the
1 Liu J, Fan D. Hepatitis B in China.
Lancet 2007; 369: 1582-1583
2 Chen CJ, Wang LY, Yu MW. Epidemiology of
hepatitis B virus infection in the Asia-Pacific region. J
Gastroenterol Hepatol 2000; 15 Suppl: E3-E6
3 Younossi ZM, Guyatt G, Kiwi M, Boparai N,
King D. Development of a disease specific questionnaire to measure
health related quality of life in patients with chronic liver disease.
Gut 1999; 45: 295-300
4 Bayliss MS, Gandek B, Bungay KM, Sugano D,
Hsu MA, Ware JE Jr. A questionnaire to assess the generic and
disease-specific health outcomes of patients with chronic hepatitis C.
Qual Life Res 1998; 7: 39-55
5 Gralnek IM, Hays RD, Kilbourne A, Rosen HR,
Keeffe EB, Artinian L, Kim S, Lazarovici D, Jensen DM, Busuttil RW,
Martin P. Development and evaluation of the Liver Disease Quality of
Life instrument in persons with advanced, chronic liver disease--the
Am J Gastroenterol
2000; 95: 3552-3565
6 van der Plas SM, Hansen BE, de Boer JB,
Stijnen T, Passchier J, de Man RA, Schalm SW.
The Liver Disease Symptom Index 2.0; validation of a
disease-specific questionnaire. Qual Life Res 2004; 13:
7 Spiegel BM, Bolus R, Han S, Tong M,
Esrailian E, Talley J, Tran T, Smith J, Karsan HA, Durazo F, Bacon B,
Martin P, Younossi Z, Hwa-Ong S, Kanwal F. Development and validation of
a disease-targeted quality of life instrument in chronic hepatitis B:
the hepatitis B quality of life instrument, version 1.0. Hepatology
2007; 46: 113-121
8 Lee EH, Cheong JY, Cho SW, Hahm KB, Kim HY,
Park JJ, Lee DH, Kim SK, Choi SR, Lee ST, Moon SM. Development and
psychometric evaluation of a chronic liver disease-specific quality of
life questionnaire. J Gastroenterol Hepatol 2008; 23:
9 Ferrer M, Cordoba J, Garin O, Olive G,
Flavia M, Vargas V, Esteban R, Alonso J. Validity of the Spanish version
of the Chronic Liver Disease Questionnaire (CLDQ) as a standard outcome
for quality of life assessment. Liver Transpl 2006; 12:
10 Rucci P, Taliani G, Cirrincione L, Alberti
A, Bartolozzi D, Caporaso N, Colombo M, Coppola R, Chiaramonte M, Craxi
A, De Sio I, Floreani AR, Gaeta GB, Persico M, Secchi G, Versace I, Mele
A. Validity and reliability of the Italian version of the Chronic Liver
Disease Questionnaire (CLDQ-I) for the assessment of health-related
quality of life. Dig Liver Dis 2005; 37: 850-860
11 Sobhonslidsuk A, Silpakit C, Kongsakon R,
Satitpornkul P, Sripetch C. Chronic liver disease questionnaire:
translation and validation in Thais. World J Gastroenterol 2004;
12 Wu CH, Deng QW, Ji XS, Yan LM. Preliminary
Use of the CLDQ in Chronic Hepatitis B Patients. Zhongguo Linchuang
Xinlixue Zhazhi 2003; 11: 60-62
13 Hauser W, Schnur M, Steder-Neukamm U, Muthny
FA, Grandt D. Validation of the German version of the Chronic Liver
Disease Questionnaire. Eur J Gastroenterol Hepatol 2004; 16:
14 Wild D, Grove A, Martin M, Eremenco S,
McElroy S, Verjee-Lorenz A, Erikson P. Principles of Good Practice for
the Translation and Cultural Adaptation Process for Patient-Reported
Outcomes (PRO) Measures: report of the ISPOR Task Force for Translation
and Cultural Adaptation. Value Health 2005; 8: 94-104
15 Beaton DE, Bombardier C, Guillemin F, Ferraz
MB. Guidelines for the process of cross-cultural adaptation of
self-report measures. Spine 2000; 25: 3186-3191
16 Lam CL, Gandek B, Ren XS, Chan MS. Tests of
scaling assumptions and construct validity of the Chinese (HK) version
of the SF-36 Health Survey.
1998; 51: 1139-1147
17 Lam ETP, Lam CLK, Lo YYC, Grandek B.
Psychometrics and population norm of the Chinese (HK) SF-36 Health
Survey_Version 2. HK Pract 2008; 30: 185-198
18 Campbell DT, Fiske DW. Convergent and
discriminant validation by the multitrait-multimethod matrix. Psychol
Bull 1959; 56: 81-105
19 Cohen J. Statistical power analysis for the
behavioral sciences. 2nd ed. Hillsdale, N.J.: L. Erlbaum Associates,
20 Terwee CB, Bot SD, de Boer MR, van der Windt
DA, Knol DL, Dekker J, Bouter LM, de Vet HC. Quality criteria were
proposed for measurement properties of health status questionnaires.
J Clin Epidemiol 2007; 60: 34-42
21 The Netherlands Cancer Institute, Amsterdam.
Assessing health status and quality-of-life instruments: attributes and
review criteria. Qual Life Res 2002; 11: 193-205
22 Public Health Report No. 3. Viral hepatitis & liver
cancer and unintentional injuries in children. Hong Kong: Dept. of
Health, 1998: 6-16
23 Yuen MF, Yuan HJ, Wong DK, Yuen JC, Wong WM,
Chan AO, Wong BC, Lai KC, Lai CL. Prognostic determinants for chronic
hepatitis B in Asians: therapeutic implications. Gut 2005; 54:
24 Foster GR, Goldin RD, Thomas HC. Chronic
hepatitis C virus infection causes a significant reduction in quality of
life in the absence of cirrhosis. Hepatology 1998; 27:
25 Gandek B, Lam CLK. Evaluating the SF-36v2 in
Hong Kong. Qual Life Res 2005; 14: 2098
26 Lam CLK, Lauder IJ, Lam TP, Gandek B.
Population based norming of the Chinese (HK) version of the SF-36 health
survey. HK Pract 1999; 21: 460-470
27 Schulz KH, Kroencke S, Ewers H, Schulz H,
Younossi ZM. The factorial structure of the Chronic Liver Disease
Questionnaire (CLDQ). Qual Life Res 2008; 17: 575-584
Editor Li LF L- Editor Webster JR E- Editor