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Quality of life in Chinese patients with inflammatory bowel disease:validation of the Chinese translation of the Inflammatory BowelDisease Questionnaire
R. W. L. LEONG, Y. T. LEE, J . Y. L. CHING & J. J . Y. SUNG
Department of Medicine and Therapeutics, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin,
Hong Kong, China
Accepted for publication 12 December 2002
SUMMARY
Background: Health-related quality of life is an import-
ant outcome measure in inflammatory bowel disease.
The Inflammatory Bowel Disease Questionnaire is a
quality of life questionnaire that has not been validated
previously in Chinese patients with inflammatory bowel
disease.
Aim: To develop and validate a Chinese translation of
the Inflammatory Bowel Disease Questionnaire, specif-
ically determining its construct validity, discriminant
ability, reliability and sensitivity to change.
Methods: We developed a Chinese version of the Inflam-
matory Bowel Disease Questionnaire. Chinese patients
with Crohn’s disease and ulcerative colitis completed
the Chinese Inflammatory Bowel Disease Questionnaire
and visual analogue scales measuring systemic, social,
bowel and emotional well-being. Patients also comple-
ted a validated Chinese SF-36 generic quality of life
questionnaire, the Crohn’s disease activity index or the
clinical activity index for ulcerative colitis.
Results: One hundred and thirty-five patients (59 with
Crohn’s disease and 76 with ulcerative colitis) were
enrolled, 99 of whom also completed the Chinese
Inflammatory Bowel Disease Questionnaire for a sec-
ond time. The Chinese Inflammatory Bowel Disease
Questionnaire correlated well with the SF-36 for all
four domains (Spearman: r ¼ 0.55–0.80), the Crohn’s
disease activity index (r ¼ )0.62–0.72) and the clin-
ical activity index for ulcerative colitis (r ¼ )0.44–
0.68), as well as with the visual analogue scales. The
Chinese Inflammatory Bowel Disease Questionnaire
accurately distinguished between active and inactive
disease. Test–re-test reliability showed excellent intra-
class correlation (0.76–0.92; all P < 0.001). The
Chinese Inflammatory Bowel Disease Questionnaire
was also sensitive to changes in disease activity
(P < 0.05).
Conclusion: The Chinese Inflammatory Bowel Disease
Questionnaire is a valid and reliable test that correlates
well with the patients’ subjective well-being and clinical
disease activity.
INTRODUCTION
Inflammatory bowel disease is a chronic debilitating
illness with a significant impact on health status.1
Intestinal and extra-intestinal disease activity, surgical
interventions, drug-induced side-effects and related
psychosocial factors all adversely impair the quality of
life. Activity indices developed to score clinical disease
activity focus mainly on the physical and biological
aspects,2–4 but fail to identify the impact of inflamma-
tory bowel disease on the patients’ perceived quality of
life, especially their emotional and social well-being.1, 5
Health-related quality of life is a global measure of the
subjective experience, from the patients’ standpoint, of
Correspondence to: Professor J. J. Y. Sung, Department of Medicine and
Therapeutics, Prince of Wales Hospital, Shatin, N.T., Hong Kong, China.
E-mail: [email protected]
Aliment Pharmacol Ther 2003; 17: 711–718. doi: 10.1046/j.0269-2813.2003.01489.x
� 2003 Blackwell Publishing Ltd 711
good health or ill health, and how it affects their daily
lives.6 Health economics and therapeutic trials are
increasingly taking into account health-related quality
of life, as it has a direct bearing on the economic burden
incurred by disease states and on the patients’ overall
health status and level of functioning. The increasing
interest in quality of life issues in gastrointestinal
diseases has been demonstrated by the dramatic
increase in the number of publications on such issues
in recent years.6 Questionnaires, both generic and
disease specific, have shown that patients with inflam-
matory bowel disease have an impaired health-related
quality of life compared with healthy controls, and
patients with Crohn’s disease generally have a poorer
health-related quality of life than patients with ulcera-
tive colitis.7, 8 Multinational trials are becoming increas-
ingly common and questionnaires are now translated
into different languages. Such instruments, however,
can be unfavourably influenced by language and
idiomatic differences when translated, and, more
importantly, by cultural differences in the perception
of health problems and societal values placed upon
these problems.9, 10 Reliability and cross-cultural
validation of translated questionnaires are therefore
mandatory.
The Inflammatory Bowel Disease Questionnaire
(IBDQ) takes into consideration the four domains of
bowel, systemic, emotional and social disturbances to
calculate a score that reflects the disease-specific
health-related quality of life.7 The IBDQ has been
shown to be reliable in the clinical setting and
sensitive to changes over time,6, 8 and has also been vali-
dated when translated into different languages.11–14
The incidence of inflammatory bowel disease in the
Chinese population is increasing, and the quality of life
of Chinese patients with inflammatory bowel disease is
unknown.15 As yet, the IBDQ has not been translated
into Chinese or tested on Chinese patients. Our aim
was to develop and validate a Chinese version of the
IBDQ.
MATERIALS AND METHODS
Patients
Consecutive Chinese patients with inflammatory bowel
disease, aged 17–75 years, were recruited from the
Prince of Wales Hospital, Hong Kong, China, which
serves a catchment population of over 1 million people
and is a tertiary referral centre with an interest in
inflammatory bowel disease. Inclusion criteria were
definite Crohn’s disease or ulcerative colitis for at least
6 months. The diagnosis of ulcerative colitis and
Crohn’s disease was made according to the Lennard-
Jones criteria.16 All patients were genetically homogen-
eous native southern Chinese, and Caucasians were
excluded. Additional exclusion criteria were the inabil-
ity to comprehend or complete the questionnaire, and
the presence of a psychiatric disorder, stoma or
malignancy.
Measurements
Chinese IBDQ. The IBDQ consists of 32 questions
divided into bowel-related, systemic, emotional and
social domains.7 Each question is answered with a
Likert graded response in the range 1–7 (1, worst
function; 7, best function). The final score ranges from
32 to 224, with a higher score indicating a better
quality of life. The translation–back-translation tech-
nique was used to translate the IBDQ into Chinese, and
was in accordance with previous questionnaire trans-
lations by the Department of Medicine, Chinese Univer-
sity of Hong Kong, Hong Kong, China. A bilingual
native Chinese gastroenterologist (YTL) performed the
initial translation into Chinese, which was reviewed and
revised by three other bilingual gastroenterologists
familiar with inflammatory bowel disease. The official
language translator of the hospital then independently
performed the back-translation from Chinese into
English. The back-translation was verified with the
original IBDQ and approved. Pilot test subjects with
inflammatory bowel disease given the Chinese IBDQ
found that it was comprehensible and easy to complete,
and no further changes were made.
Self-administration of the English IBDQ has been
validated previously and the same technique was
employed in this trial.17 Patients were asked to complete
the Chinese IBDQ to reflect the quality of life of the
previous 2 weeks. On completion, a research nurse
interviewed the patients and any difficulties encoun-
tered with the questionnaire were addressed.
Patients also completed a second Chinese IBDQ at least
2 weeks after, but within a month of, the first survey to
determine intra-individual variations. They indicated
whether, during the interval period, their IBDQ had
deteriorated, remained the same, or improved. The
university ethics committee approved the protocol and
712 R. W. L. LEONG et al.
� 2003 Blackwell Publishing Ltd, Aliment Pharmacol Ther 17, 711–718
signed informed consent was obtained from the study
subjects.
SF-36. For validation purposes, patients also completed
a previously validated Chinese translation of the
Medical Outcomes Study (MOS) 36-Item Short Form
Health Survey (SF-36)18 and visual analogue scales
(VAS) of well-being. The SF-36 is a generic, non-
disease-specific, health-related quality of life assessment
questionnaire that assesses the domains of physical
functioning, physical health, bodily pain, general
health, vitality, social functioning, emotional health
and mental health. A higher score indicates a better
health status. The SF-36 has been extensively validated
and used in a wide variety of medical conditions,19, 20
including gastrointestinal diseases,21 and has been
translated into and validated in Hong Kong Chinese.18
VAS. The VAS is a horizontal Likert scale measured
from 0 to 10 cm. Four VAS were measured for the
domains of general well-being, bowel function, emo-
tional health and social health to correspond with the
four domains of the IBDQ.
Disease activity indices. A gastroenterologist (RWLL),
blind to the results of the Chinese IBDQ, VAS and SF-36,
independently interviewed the patients at the time of
completion of the questionnaires and scored the disease
activity by means of the Crohn’s disease activity index
(CDAI)3 and the clinical activity index (CAI) for
ulcerative colitis.4 The CDAI was scored according to
the parameters of soft stool frequency, abdominal pain,
general well-being, extra-intestinal manifestations, fis-
tulas, abdominal mass, use of opiates for diarrhoea,
anaemia and weight loss, with a higher score indicating
more severe disease activity and a score of < 150
considered as remission.3 The CAI was calculated from
the frequency of diarrhoea, nocturnal diarrhoea, visible
blood in stool, faecal incontinence, abdominal pain,
general well-being, abdominal tenderness and the need
for anti-diarrhoeal drugs. The total score ranged from 0
to 21, with remission defined as a score of below 10.4
Construct validity and discriminant ability. Non-paramet-
ric statistics were used for the analysis of the quality of
life scores, and were calculated separately for Crohn’s
disease and ulcerative colitis. Construct validity refers to
how well the equivalent domain scores of the Chinese
IBDQ, VAS and SF-36 correlate with each other, and
was analysed using the Spearman correlation coeffi-
cient. Discriminant ability refers to how well the
Chinese IBDQ differentiates active inflammatory bowel
disease from quiescent disease, and was compared
with the disease activity indices using the Mann–
Whitney U-test.
Test–re-test reliability and sensitivity to change. Patients
who completed the follow-up Chinese IBDQ within
1 month of the initial questionnaire were divided into
those with stable disease activity and those with
changed disease activity. Patients with stable disease
was defined as those who reported no significant change
in symptoms and a minimal change in disease activity
index where available (change in CDAI < 50 or
CAI < 4). The reliability assessed the homogeneity of
the Chinese IBDQ in those with stable disease, using the
intra-class correlation coefficient (ICC), standardized
Cronbach’s alpha and Wilcoxon signed rank test. An
ICC of > 0.8 indicates excellent reliability. Sensitivity to
change measured the ability of the Chinese IBDQ to
detect a change in disease activity using the Spearman
correlation coefficient.
Statistical analyses were performed using SPSS version
10.0. A P value of less than 0.05 was deemed to be
statistically significant.
RESULTS
Patients
One hundred and forty-five consecutive Chinese
patients with inflammatory bowel disease fulfilled the
inclusion criteria. Ten patients were excluded due to
poor comprehension of or gross failure to complete the
Chinese IBDQ (four patients), presence of a stoma (four
patients), refusal (one patient) and previously diagnosed
anxiety/depression (one patient). One hundred and
thirty-five patients were included in the study, 59 with
Crohn’s disease and 76 with ulcerative colitis. The
mean age of the patients was 41 years and 40% were
females. The demographic data of the patients are listed
in Table 1 and Figure 1 summarizes the recruitment of
patients for this study. Ninety-nine patients completed
the questionnaire a second time at a mean of 20 days
following the initial questionnaire. Seventy-seven of
these patients remained stable, and 22 showed a change
in disease activity. Missing data were uncommon,
accounting for less than 1% of responses.
CHINESE IBDQ 713
� 2003 Blackwell Publishing Ltd, Aliment Pharmacol Ther 17, 711–718
Construct validity (Table 2)
To validate that the Chinese IBDQ reflects the disease
activity and generic quality of life scores, correlation was
performed with the previously validated Chinese SF-36,
clinical activity indices and VAS. The Chinese IBDQ
domains for both Crohn’s disease and ulcerative colitis
correlated strongly and significantly with the SF-36
score (all four IBDQ domains, P < 0.001). The correla-
tion was strongest for the systemic domain (Spearman
correlation coefficients: r ¼ 0.801 and r ¼ 0.748 for
Crohn’s disease and ulcerative colitis, respectively),
followed by the emotional domain (0.791 and 0.749),
the bowel function domain (0.773 and 0.549) and the
social domain (0.673 and 0.567). For all Chinese IBDQ
domains, the correlation with SF-36 was stronger for
Crohn’s disease than for ulcerative colitis.
Similarly, the Chinese IBDQ scores for Crohn’s disease
and ulcerative colitis correlated well and significantly
with CDAI and CAI, respectively (all four domains,
P < 0.001). The correlation coefficients for disease
activity were as follows: bowel function domain,
r ¼ ) 0.719 and r ¼ )0.675 for Crohn’s disease and
ulcerative colitis, respectively; systemic domain,
) 0.642 and ) 0.511; emotional domain, )0.646 and
) 0.440; social domain, )0.623 and )0.485. Again,
the correlation scores were stronger for Crohn’s disease
than for ulcerative colitis.
The Chinese IBDQ domain scores correlated well with
VAS for Crohn’s disease only (all P < 0.001), but less
Table 1. Patient demographics
Total
IBD
Crohn’s
disease
Ulcerative
colitis
Total number 135 59 76
Males/females 81/54 42/17 39/37
Mean age (years) (s.d.) 41.5 (12.8) 39.2 (11.2) 43.5 (13.8)
Mean disease
duration (years)
6.7 7.3 6.2
IBD, inflammatory bowel disease; s.d., standard deviation.
145 Eligible patients
135 Eligible patients(59CD, 76UC)
10 excluded4 poor comprehension4 stoma1 refused1 psychiatric
99 Completed 2nd questionnaire
77 Unchanged disease activity
Reliability testing
22 Changed disease activity(15 improved, 7 deteriorated)
Sensitivity testing
Figure 1. Flow diagram of the study. CD, Crohn’s disease; UC,
ulcerative colitis.
Table 2. Construct validity of Chinese Inflammatory Bowel Disease Questionnaire (IBDQ) for Crohn’s disease and ulcerative colitis.
The Spearman correlation coefficients and P values of the Chinese IBDQ compared with the Chinese SF-36, disease activity indices and
visual analogue scales (VAS) are shown
Chinese IBDQ domain
SF-36 Disease activity index* VAS
r P r P r P
Crohn’s disease (n ¼ 59)
Bowel 0.773 < 0.001 ) 0.719 < 0.001 0.599 < 0.001
Systemic 0.801 < 0.001 ) 0.642 < 0.001 0.615 < 0.001
Social 0.673 < 0.001 ) 0.623 < 0.001 0.643 < 0.001
Emotional 0.791 < 0.001 ) 0.646 < 0.001 0.665 < 0.001
Ulcerative colitis (n ¼ 76)
Bowel 0.549 < 0.001 ) 0.675 < 0.001 0.322 0.10
Systemic 0.748 < 0.001 ) 0.511 < 0.001 0.332 0.008
Social 0.567 < 0.001 ) 0.485 < 0.001 0.113 0.378
Emotional 0.749 < 0.001 ) 0.440 < 0.001 0.445 < 0.001
SF-36, Medical Outcomes Study (MOS) 36-Item Short Form Health Survey.
* Crohn’s disease, Crohn’s disease activity index; ulcerative colitis, clinical activity index for ulcerative colitis.
714 R. W. L. LEONG et al.
� 2003 Blackwell Publishing Ltd, Aliment Pharmacol Ther 17, 711–718
well for ulcerative colitis. The correlations were as
follows: bowel function domain, r ¼ 0.599 and
r ¼ 0.332 for Crohn’s disease and ulcerative colitis,
respectively; systemic domain, 0.615 and 0.332; social
domain, 0.643 and 0.113; emotional domain, 0.665
and 0.445. For ulcerative colitis, the bowel function and
social domains did not produce statistically significant
correlations (P > 0.05).
Discriminant ability (Table 3)
To validate that the Chinese IBDQ scores differ signifi-
cantly in patients in remission vs. those with active
disease, discriminant ability was measured. The Chinese
IBDQ scores of patients in remission were compared
with those with active disease. Disease activity was
determined objectively by the top and bottom tertile
VAS scores and the disease activity indices. In Crohn’s
disease, the Chinese IBDQ discriminated well between
groups of patients either in remission or with active
disease as measured by both VAS and CDAI (P < 0.001
for all domains). In ulcerative colitis, the Chinese IBDQ
also discriminated well between active and inactive CAI
(P < 0.001–0.005). For the differentiation of active and
inactive disease according to VAS, however, all domains
showed significance (P < 0.003–0.032), apart from the
bowel function domain which showed a strong trend
towards significance (P ¼ 0.052). Once again, the
discriminant ability of the Chinese IBDQ was more
definite for Crohn’s disease than for ulcerative colitis.
The association was stronger with the inflammatory
bowel disease activity indices rather than with the more
subjective VAS.
Test–re-test reliability (Table 4)
To validate that the Chinese IBDQ was internally
consistent amongst individuals whose disease activity
remained stable, the test–re-test reliability was meas-
ured. Patients with stable disease activity completed the
Chinese IBDQ on two occasions at a mean of 20 days
apart, and paired results were compared with the
Wilcoxon signed rank test and the ICC. The Wilcoxon
signed rank test for all four domains showed that there
was no statistical difference in the Chinese IBDQ in
those with unchanged disease activity (paired median
Chinese IBDQ scores, P > 0.05) for Crohn’s disease
(n ¼ 38 pairs) and ulcerative colitis (n ¼ 38 pairs). The
ICC showed very high test–re-test reliability for Crohn’s
disease (ICC ¼ 0.83–0.92) and ulcerative colitis
(ICC ¼ 0.76–90) for all four domains. The reliability
was significant in all cases (P < 0.001). In general, the
Table 3. Discriminant ability of the Chinese Inflammatory Bowel Disease Questionnaire (IBDQ) for Crohn’s disease and ulcerative
colitis. The Chinese IBDQ median scores in patients with low and high disease activity according to the lowest and highest tertiles of the
visual analogue scales (VAS) and disease activity indices are shown
Chinese IBDQ domain
VAS Disease activity index*
Bottom tertile Top tertile
P
Bottom tertile Top tertile
PMedian� Median� Median§ Median–
Crohn’s disease
Bowel 65.0 46.0 < 0.001 67.0 46.0 < 0.001
Systemic 30.0 19.0 < 0.001 30.0 20.0 < 0.001
Social 75.0 52.0 < 0.001 73.0 55.0 < 0.001
Emotional 34.0 24.0 < 0.001 35.0 23.0 < 0.001
Ulcerative colitis
Bowel 58.5 51.0 0.052 64.0 48.0 < 0.001
Systemic 28.5 19.0 0.003 28.0 18.0 < 0.001
Social 69.5 52.0 0.016 70.0 51.0 0.001
Emotional 33.0 27.0 0.032 34.0 25.5 0.005
* Crohn’s disease, Crohn’s disease activity index; ulcerative colitis, clinical activity index for ulcerative colitis.
� Crohn’s disease, n ¼17; ulcerative colitis, n ¼ 20.
� Crohn’s disease, n ¼17; ulcerative colitis, n ¼ 21.
§ Crohn’s disease, n ¼19; ulcerative colitis, n ¼ 23.
– Crohn’s disease, n ¼19; ulcerative colitis, n ¼ 20.
CHINESE IBDQ 715
� 2003 Blackwell Publishing Ltd, Aliment Pharmacol Ther 17, 711–718
reliability was higher for Crohn’s disease than for
ulcerative colitis.
Sensitivity to change (Table 5)
To validate that the Chinese IBDQ was sensitive to
changes in disease activity within an individual, paired
Chinese IBDQ scores were analysed in patients who
showed a change in disease activity. To provide an
adequate sample size for this test, Crohn’s disease and
ulcerative colitis patients were pooled together (n ¼ 22
pairs). Each pair consisted of a lower Chinese IBDQ score
(indicating deterioration) compared with a higher
Chinese IBDQ score (indicating improvement). The
Wilcoxon signed rank test demonstrated a signifi-
cant difference between the paired Chinese IBDQ scores
in all four domains (bowel function domain, P ¼ 0.005;
social domain, P ¼ 0.007; systemic domain, P ¼0.019; emotional domain, P ¼ 0.041).
DISCUSSION
The incidence of inflammatory bowel disease in China is
lower than that in Western nations, but is increasing
rapidly.15 Inflammatory bowel disease may become an
important disease in China with the ongoing Western-
ization and economic development of the country.
There is also a growing emphasis on the quality of life
as an important end-point in the measurement of
inflammatory bowel disease activity.6 The quality of life
of Chinese patients with inflammatory bowel disease is
unknown, but is of interest and importance given the
sheer volume of potential patients in the most populous
nation in the world. The previous rarity of inflammatory
bowel disease in China may result in a paucity of
disease-related information, resources and social sup-
port groups and a low level of understanding from non-
specialized doctors. These factors may adversely impair
the quality of life and a prospective study is required to
determine this. The IBDQ has been translated into
different languages11–14 and validated to be reliable. For
the first time, a Chinese translation of the IBDQ is
available.
This study showed that the Chinese translation of the
IBDQ is a valid and reliable instrument for the
assessment of patients with inflammatory bowel disease
in Hong Kong. The Chinese IBDQ showed a high degree
of construct validity. The Chinese IBDQ scores correlated
well with the established Chinese translation of the
SF-36 and with the disease activity indices (CDAI and
CAI). There was good discriminant ability and the
Chinese IBDQ was able to differentiate between patients
with inactive and active disease as indicated by
subjective VAS scores and objective disease activity
indices. The test–re-test reliability also demonstrated
good internal validity in the paired intra-individual
scores in those with stable disease activity. To improve
the accuracy of the reliability test, we performed a
follow-up survey within 1 month of the initial ques-
tionnaire to ensure the accurate recall of any change in
disease activity during the interval period. In patients
who showed a change in disease activity, the Chinese
IBDQ changed correspondingly. All four domains pro-
duced similar results. In general, the results were very
acceptable and comparable with other translations.11–14
Although the Chinese IBDQ scores for ulcerative colitis
correlated less well with some of the VAS domain
scores, the more important comparisons with the CAI
were all significant. The poorer correlation with VAS
Table 5. Sensitivity to change of the Chinese Inflammatory Bowel
Disease Questionnaire (IBDQ) for combined Crohn’s disease and
ulcerative colitis (n ¼ 22). The paired median Chinese IBDQ
scores changed significantly with changing disease activity
(relative deterioration and improvement)
Chinese IBDQ domain Deterioration Improvement P
Bowel 44.0 50.5 0.005
Systemic 19.1 21.7 0.019
Social 50.2 57.9 0.007
Emotional 26.0 29.0 0.041
Table 4. Test–re-test reliability of the Chinese Inflammatory
Bowel Disease Questionnaire (IBDQ) for Crohn’s disease and
ulcerative colitis. The follow-up paired median Chinese IBDQ
scores remained stable in patients in whom the disease activity
was unchanged
Chinese IBDQ domain Baseline Follow-up ICC P
Crohn’s disease (n ¼ 38 pairs)
Bowel 56.0 57.0 0.8767 < 0.001
Systemic 25.0 24.0 0.8321 < 0.001
Social 63.0 61.0 0.9066 < 0.001
Emotional 32.5 33.0 0.9164 < 0.001
Ulcerative colitis (n ¼ 38 pairs)
Bowel 58.0 57.0 0.7572 < 0.001
Systemic 26.5 24.0 0.8781 < 0.001
Social 67.0 61.3 0.8712 < 0.001
Emotional 34.0 33.0 0.9016 < 0.001
ICC, intra-class correlation coefficient.
716 R. W. L. LEONG et al.
� 2003 Blackwell Publishing Ltd, Aliment Pharmacol Ther 17, 711–718
may indicate the lack of reliability of VAS, which is a
crude measure of well-being subject to variable inter-
pretation by patients. In ulcerative colitis, the appear-
ance of a small amount of red blood in the bowel
motion, which can commonly occur with mild distal
disease, is often misinterpreted by patients to indicate a
more severe flare. This may then be reflected by a high
grading on the VAS score, whereas the corresponding
Chinese IBDQ and CAI scores do not reflect the
dysfunction to the same degree. In addition, most
patients with ulcerative colitis were in remission at the
time of completion of the questionnaire, and the lack of
a range of disease activity may make it difficult for the
Chinese IBDQ scale to produce a good correlation. The
higher construct validity for Crohn’s disease compared
with ulcerative colitis was also noted in the Greek
translation of the IBDQ.14
The very encouraging results in patients with Crohn’s
disease in all domains and in all comparisons indicate
that there are no significant idiomatic disparities, cul-
tural barriers or societal differences with this translation
of the questionnaire. Importantly, patients had no
difficulty in completing the self-administered question-
naire. It was easily incorporated into the routine at the
out-patient department without any significant changes
to the routines of the staff. Consultation was also
obtained from the original authors of the questionnaire
at McMaster University and, to our knowledge, this
translation is the only translation into an Asian language
that has been performed with their approval and help.
In conclusion, the Chinese IBDQ is a valid and reliable
instrument that correlates well with the patients’
subjective well-being and clinical disease activity. We
believe that the Chinese IBDQ will be a useful tool in
patients with inflammatory bowel disease for the assess-
ment of the quality of life in clinical trials and health
surveys and for the assessment of therapeutic efficacy.
ACKNOWLEDGEMENTS
The use of the IBDQ, authored by Dr Jan Irvine, was
made under license from McMaster University, Hamil-
ton, Canada.
The use of the Chinese (HK) SF-36 was by agreement
with Dr Cindy Lam, University of Hong Kong, Hong
Kong SAR.
Dr R. W. L. Leong is supported by an Overseas
Research Fellowship from the University of Western
Australia.
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