Valid and Convenient Questionnaire Assessment of Chinese Body Constitution: Item Characteristics, Reliability, and Construct Validation

Abstract

Background
Body constitution is a fundamental concept in traditional Chinese medicine (TCM) for clinical diagnosis, treatment of illness, and community-based health promotion. Clinical assessment of patients’ body constitutions, however, has never been easy and consistent, even by well-trained clinicians and TCM practitioners. Therefore, questionnaires such as the popular Constitution in Chinese Medicine Questionnaire (CCMQ) can be an appealing and convenient assessment alternative. The present research borrowed advanced methodologies for questionnaire development in psychology and other social sciences to examine the performance of the CCMQ in terms of (i) the strength of relations of each item with its designated constitution, (ii) the reliabilities of each constitution, and (iii) the overall 9-constitution structure. This research provided empirical evidence to support the use of the CCMQ and proposed directions for refinement in future revisions of the CCMQ or similar measures.

Methods
A total of 1571 volunteers from three villages in southern China participated in the CCMQ survey. The item characteristics, reliabilities, interconstitution correlations, and confirmatory factor analysis of the 9-body-constitution structure were examined.

Results
The results generally supported the appropriateness of the clinical observations (the questionnaire items) and the CCMQ 9-constitution classification structure. Nevertheless, some relatively weaker items, item pairs with similar meanings, and highly overlapping constitutions were identified for future CCMQ revisions.

Conclusion
The CCMQ measured the 9 constitutions efficiently and with reasonably good reliability and construct validity. Given the various challenges to assessing TCM body constitutions even by experienced clinicians, the CCMQ provides an appealing alternative to measure the Chinese body constitutions of healthy participants in large-scale research or community health promotion programs. The present study also demonstrated how advanced methodologies in social sciences can help validate and refine the CCMQ and similar complementary medicine measures.

Full text

ORIGINAL RESEARCH
Valid and Convenient Questionnaire Assessment
of Chinese Body Constitution: Item Characteristics,
Reliability, and Construct Validation
Taoying Lu
1–3
, Jingwen Yan
4
, Jianfang Chang
5
, Jianxiong Cai
1–3
, Lingjia Yin
1,3,6
,
Jiamin Yuan
1,7
, Li Huang
1,7
, Yingshuai Li
8
, Minghua Bai
9
, Kit-Tai Hau
5
, Darong Wu
1–3
,
Zhimin Yang
1,7
1
State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Afliated Hospital of Guangzhou University of Chinese Medicine,
Guangzhou, People’s Republic of China;
2
Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome, The
Second Afliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China;
3
Program for Outcome Assessment
in TCM, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, People’s Republic of China;
4
The Second Clinical Medical College of
Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China;
5
Department of Education Psychology, The Chinese University of
Hong Kong, Hong Kong SAR, People’s Republic of China;
6
Department of Global Public Health, Karolinska Institutet, Stockholm, Sweden;
7
Health
Construction Administration Center, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, People’s Republic of China;
8
National Institute
of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, People’s Republic of China;
9
School of Traditional
Chinese Medicine/National Institute of TCM Constitution and Preventive Medicine, Beijing University of Chinese Medicine, Beijing, People’s Republic
of China
Correspondence: Darong Wu; Zhimin Yang, State Key Laboratory of Dampness Syndrome of Chinese Medicine, The Second Afliated Hospital of
Guangzhou University of Chinese Medicine, 111 Dade Road, Guangzhou, 510120, People’s Republic of China, Tel +86 13808869436; +86 13822296363,
Email darongwu@gzucm.edu.cn; yangyo@vip.tom.com
Background: Body constitution is a fundamental concept in traditional Chinese medicine (TCM) for clinical diagnosis, treatment of
illness, and community-based health promotion. Clinical assessment of patients’ body constitutions, however, has never been easy and
consistent, even by well-trained clinicians and TCM practitioners. Therefore, questionnaires such as the popular Constitution in
Chinese Medicine Questionnaire (CCMQ) can be an appealing and convenient assessment alternative. The present research borrowed
advanced methodologies for questionnaire development in psychology and other social sciences to examine the performance of the
CCMQ in terms of (i) the strength of relations of each item with its designated constitution, (ii) the reliabilities of each constitution,
and (iii) the overall 9-constitution structure. This research provided empirical evidence to support the use of the CCMQ and proposed
directions for renement in future revisions of the CCMQ or similar measures.
Methods: A total of 1571 volunteers from three villages in southern China participated in the CCMQ survey. The item characteristics,
reliabilities, interconstitution correlations, and conrmatory factor analysis of the 9-body-constitution structure were examined.
Results: The results generally supported the appropriateness of the clinical observations (the questionnaire items) and the CCMQ
9-constitution classication structure. Nevertheless, some relatively weaker items, item pairs with similar meanings, and highly
overlapping constitutions were identied for future CCMQ revisions.
Conclusion: The CCMQ measured the 9 constitutions efciently and with reasonably good reliability and construct validity. Given
the various challenges to assessing TCM body constitutions even by experienced clinicians, the CCMQ provides an appealing
alternative to measure the Chinese body constitutions of healthy participants in large-scale research or community health promotion
programs. The present study also demonstrated how advanced methodologies in social sciences can help validate and rene the CCMQ
and similar complementary medicine measures.
Keywords: Chinese constitution, body constitution, CCMQ, Constitution in Chinese Medicine Questionnaire, reliability, construct validity
Introduction
Body constitution, an ancient concept of traditional Chinese medicine (TCM), postulates that people have relatively
stable unique morphological structures and physiological, psychological, and functional activities due to genetic
Patient Preference and Adherence 2022:16 1875–1884 1875
© 2022 Lu et al. This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php
and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work
you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For
permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php).
Patient Preference and Adherence Dovepress
open access to scientific and medical research
Open Access Full Text Article
Received: 5 May 2022
Accepted: 15 July 2022
Published: 2 August 2022

disposition, acquired factors, and self-regulation.
1
People can be classied, therefore, by these similarities and differences
in body constitution into many different “types”.
2–4
The determination of body constitution helps the effective treatment
of illness, health maintenance, and disease prevention. Given that our body constitutions are partly determined from birth
through heredity, the knowledge of our constitutions greatly facilitates health maintenance and disease prevention.
Accurately identifying body constitution has never been easy, even for experienced clinicians. Interrater consistency
was a major concern,
5,6
and people tried to standardize and develop structured TCM interviews.
7
Even for 5-year or more
experienced acupuncturists, for example, 4 to 6 of them were needed to obtain reliable yin and yang deciency ratings.
8
Training helped improve interrater reliability from 0.11 to 0.62 after three rounds of discussion and training.
9
Reviews by
Brien and Birch
10
also showed that the reliabilities of pulse diagnosis were low to very good, while those of tongue and
other diagnoses varied.
Obviously, more training and having several clinicians diagnose each patient or research participant is time-
consuming, resource-demanding, and impractical for large-scale empirical research or community health promotion
programs. A high-quality questionnaire, therefore, becomes an appealing alternative. Despite such a demand, construct-
ing a valid and reliable instrument is also challenging, particularly in developing an assessment for the healthy general
population. It is difcult for clinicians to accurately assess patients with observable illness symptoms, so developing
a questionnaire applicable to the nonsymptomatic healthy general population will be even more difcult. Such attempts
included the questionnaires on cold, heat, complex, and phlegm.
11,12
Among them,
13–17
the Constitution in Chinese
Medicine Questionnaire (CCMQ)
18–20
was probably the most comprehensive and widely used.
The CCMQ by Wang et al was developed in China
18–20
but also has been translated and used in Canada, Japan,
Korea, and the USA, among other countries.
21–23
It consists of 60 items with 9 subscales, each measuring one Chinese
body constitution. The items (clinical observations; eg, “Did you get tired easily?”) measure participants’ feelings or
symptoms in the last year. It has been shown to have reasonably good psychometric properties
24,25
in various medical
settings.
26–30
Versions of 60, 41, and 30 items in Chinese, English, and Japanese
23,31
have been developed and
evaluated,
32
with over 2277 papers, 55% of which are journal articles published between 2006 and 2016.
33
Despite its popularity, challenges to its use included
34
(i) difculty for people with limited education to understand
some items, (ii) questionable classication of some items, (iii) many items classied as mixed body constitution, (iv)
some items cross-linked to multiple body constitutions,
34–36
(v) the originally proposed structure could not be reproduced
with empirical data (eg, 8 factors found in research despite the 9 originally proposed in CCMQ),
32,37
and (vi) items not
allocated to their intended constitutions (many items in some constitutions, but few items in others).
32,37
The interrela-
tions among the original items (indicators) were not carefully examined in the previous factor analyses. The more
appropriate conrmatory factor analysis was used with patients only in Hong Kong SAR to conrm its original
constitution structure.
38
However, the results were dubious, with 5 items with standardized loadings larger than 1, 7
items in the unexpected direction (negative instead), and 1 item with extremely low loading (−0.01), suggesting likely
inappropriate modeling and the misclassication of items.
The present study contributed academically by adopting advanced methodologies commonly used in psychology and
other social sciences questionnaire development.
39
Importantly, the traditional exploratory factor analysis used in earlier
studies
32,37
was replaced by the more appropriate conrmatory factor analysis in this study. The more commonly used
exploratory factor analysis can help researchers group items with an unknown structure into factors.
39,40
In contrast,
conrmatory factor analysis works with items with a known grouping (factors) and provides statistics (t indices) to
inform researchers whether such a grouping is supported or not. Thus, as the grouping (structure) of the CCMQ items
was provided by Wang et al,
18–20
conrmatory factor analysis was the proper method to examine the correctness of the
original item classications.
Specically, this study provides empirical evidence on the construct validation and reliability information of the
CCMQ. The objectives were to examine (i) the appropriateness of each item (clinical observations of the constitutions) as
a measure of its original intended constitutions, (ii) the internal consistency reliability of each constitution, and (iii) the
convergent (coherent)/divergent (discriminating) relations among the constitutions. The study not only evaluated the
overall t of the original 9-constitution structure but also examined the suitability of each individual item in the
https://doi.org/10.2147/PPA.S373512
DovePress
Patient Preference and Adherence 2022:16
1876
Lu et al Dovepress
Powered by TCPDF (www.tcpdf.org)

instrument. The information is essential to support the use of this important CCMQ in large-scale research or community
health promotion programs when a high-quality and convenient Chinese body constitution instrument is needed.
Materials and Methods
Participants
The 1571 voluntary participants, who individually provided their consent, were residents from three villages in Foshan,
a city in Guangdong Province in the southern part of China with a population of approximately 5000. The survey was
conducted at local clinics, but only their rst-visit responses were used in the analyses, even if they made further visits
for other purposes. There were more females than males, and there were more older (older than 40) than younger
participants (Table 1).
Ethical Considerations
This study was conducted in accordance with the Declaration of Helsinki. Ethical approval was obtained for this
project from the Research Ethics Committee of Guangdong Provincial Hospital of Chinese Medicine (Reference No:
B2013-009-01/B2017-150-01). The participants provided written informed consent before answering the survey
questionnaire.
Measures
The CCMQ consisted of 60 items (clinical observations, indicators of constitutions, Table 2) categorized into 9 subscales,
each measuring one of the 9 different body constitutions, namely, Yang-decient (7 items), Yin-decient (8 items), Qi-
decient (8 items), Phlegm-dampness (8 items), Damp-heat (6 items), Stagnant Blood (7 items), Inherited Special (7
items), Stagnant Qi (7 items), and Balanced (8 items). The items were on a 5-point Likert scale, with high scores
indicating a higher likelihood of having the given constitution. Usually, a threshold of 30 or higher points on a subscale
was used to classify a person as having that body constitution.
Table 1 Demographic Characteristics of Participants (n = 1571)
Demographic Characteristic n %
Gender
Male 510 32.5
Female 1061 67.5
Age group
0–20 years old 25 1.6
21–40 years old 346 22.0
41–60 years old 571 36.3
>61 years old 628 40.0
Not disclosing/missing 1 0.1
Education
Less education /Primary school 669 42.6
Junior secondary education 375 23.9
Senior secondary education 196 12.4
Tertiary education 189 12.0
Not disclosing/missing 142 9.0
Marital status
Single 91 5.8
Married 1232 78.4
Widower, separated/divorced 84 5.3
Not disclosing/missing 164 10.4
Patient Preference and Adherence 2022:16 https://doi.org/10.2147/PPA.S373512
DovePress
1877
Dovepress Lu et al
Powered by TCPDF (www.tcpdf.org)

Table 2 Reliabilities of 9 Subscales, Item Content, and Standardized Loadings
Item Number Item Content* Factor
Loading
Scale 1 (Yang-decient constitution; α = 0.740)
Q18 Did your hands or feet feel cold or clammy? 0.710
Q19 Did you feel clod easily in your abdomen, back, lower back or knees? 0.794
Q20 Were you sensitive to cold and tend to wear more clothes than others? 0.684
Q52 Did you feel uncomfortable when you drank or ate something cold, or do
you avoid drinking or eating something cold?
0.488
Q55 Did you easily contract diarrhea when you were exposed to cold or eat
(or drink) something cold?
0.455
Scale 2 (Yin-decient constitution; α = 0.742)
Q17 Did the palms of your hands or soles of your feet feel hot? 0.341
Q21 Did your body and face feel hot? 0.488
Q35 Did your skin or lips feel dry? 0.659
Q38 Did you get hot ashes? 0.369
Q44 Did your eyes feel dry and use eye drops? 0.611
Q46 Did you often feel parched and need to drink water? 0.600
Q57 Did you get constipated easily or have dry stools? 0.473
Scale 3 (Qi-decient constitution; α = 0.725)
Q3 Did you suffer from shortness of breath? 0.604
Q4 Did you get palpitations? 0.582
Q5 Did you get dizziness easily or become giddy when standing up? 0.592
Q6 Did you prefer quietness and do not like to talk? 0.597
Q23 Did you catch colds more easily than others? 0.468
Q27 Did you sweat easily when you had a slightly increased physical activity? 0.476
Scale 4 (Phlegm-dampness constitution; α = 0.706)
Q14 Did you feel chest or stomach stufness? 0.461
Q28 Did you have an excessively oily forehead and/or T-zone? 0.616
Q42 Did you have upper eyelid swelling? 0.433
Q49 Did your mouth feel sticky? 0.403
Q50 Was your stomach/belly abby? 0.483
Q51 Did you have lots of phlegm? 0.430
Q58 Did your tongue have a thick coating? 0.579
Scale 5 (Damp-heat constitution; α = 0.767)
Q39 Did your nose or your face feel greasy, oily, or shiny? 0.703
Q41 Did you get acne or sores easily? 0.564
Q48 Did you have bitterness or a strange taste in your mouth? 0.470
Q56 Did you pass sticky stools and/or feel that your bowel movement is
incomplete?
0.606
Q59 Did your urethral canal feel hot when you urinated, or did your urine
have a dark color?
0.584
Q60 Was your vaginal discharge yellowish/Was your scrotum always wet? 0.463
Scale 6 (Stagnant Blood constitution; α = 0.638)
Q37 Did you feel pain somewhere in your body? 0.482
Q40 Did you have s dark face? 0.482
Q43 Did you get dark circles under the eyes easily? 0.566
Q45 Did your lips darker, more blue or purple than usual? 0.558
Scale 7 (Inherited Special constitution; α = 0.731)
Q24 Did you sneeze even when you did not have a cold? 0.692
Q25 Did you have runny or stuffy nose even when you did not have a cold? 0.631
Q26 Did you cough due to seasonal change, temperature change, or
unpleasant odor?
0.447
(Continued)
https://doi.org/10.2147/PPA.S373512
DovePress
Patient Preference and Adherence 2022:16
1878
Lu et al Dovepress
Powered by TCPDF (www.tcpdf.org)

Analyses
As there were more females and older participants, a weight (inverse to the group ratio) was added so that all analyses
were based on a weighted sample with equal representation of the gender and age groups. In this study, the original
structure and classications of the CCMQ items were known. Thus, conrmatory factor analysis was more appropriately
used to assess the suitability of this 9-constitution classication.
To assess whether the items (clinical observations) consistently assessed the respective constitutions, internal
consistency reliability measured by Cronbach’s alpha was computed for each of the 9 constitutions (Table 2). In the
conrmatory factor analysis, (i) the strength of the relationship of each item to the constitution (ie, factor loading)
showing possible misclassied items, (ii) the overall success in measuring the 9 constitutions (ie, model t), and (iii) the
possible weak items measuring more than one constitution (ie, correlated uniqueness in conrmatory factor analysis
terminology) were examined with the commercial software Mplus 8.1.
40
Results
Preliminary Analyses—Identication of Misclassied Items
In the rst stage of the analyses, weak items unrelated to their originally intended and other constitutions were identied
and removed. This was based on (i) Cronbach’s alpha (Table 2), (ii) Cronbach’s alpha if-item-deleted, and (iii) corrected
item-total correlations. Unless there were strong face-validity reasons, items were potentially removed if (i) they had low
corrected item-total correlations, (ii) Cronbach’s alpha was substantially improved when they were deleted, (iii) they had
low correlations with other items in the same scale, and (iv) they had low correlations with other constitutions (ie,
impossible to reassign to another constitution). Seven items were removed using these criteria (Q1, Q7, Q29, Q32, Q33,
Q36, and Q53).
Table 2 (Continued).
Item Number Item Content* Factor
Loading
Q30 Did you have allergies? eg, medicine, food, odors, pollen etc. 0.363
Q31 Did your skin get hives/urticaria easily? 0.307
Q34 Did you skin turn red and show traces when you scratched it? 0.493
Q47 Did your throat feel strange (ie, Like something was stuck or there was
a lump in your throat)?
0.420
Scale 8 (Stagnant Qi constitution; α = 0.831)
Q10 Do you get anxious and worried easily? 0.590
Q11 Did you feel sensitive, vulnerable or emotionally upset? 0.665
Q12 Were you easily scared or frightened? 0.634
Q13 Did you experience distention in the underarm or breast? 0.359
Q15 Did you sigh for no reason? 0.571
Q16 Did your body feel heavy or lethargic? 0.608
Scale 9 (Balanced constitution; all items coded in
a reversed direction, α = 0.721)
Q2 Did you get tired easily? 0.645
Q8 Did you forget things easily? 0.667
Q9 Did you feel gloomy and depressed? 0.660
Q22 Did you feel more vulnerable to the cold than others? 0.617
Q54 Did you suffer from insomnia? 0.518
Notes: *These English items were based on the translation by Jing, Wang, Wang. Data from Jing HR, Wang J, Wang Q. Preliminary compiling of English version of
Constitution in Chinese Medicine Questionnaire. J Anhui Univ Chinese Med. 2015;34(5):21–25.
31
Patient Preference and Adherence 2022:16 https://doi.org/10.2147/PPA.S373512
DovePress
1879
Dovepress Lu et al
Powered by TCPDF (www.tcpdf.org)

Strength of Relations with Respective constitutions—reliability and Factor Loadings
This study showed that items within each constitution were consistently correlated, with the reliabilities of the constitu-
tions ranging from 0.638 to 0.831 (see Table 2); the lowest reliability, 0.638, was associated with the shortest scale with
only 4 items. Conrmatory factor analysis of the 9 factors (Table 2) was conducted on the remaining 53 items, with items
grouped under their respective constitutions, and all constitutions were allowed to be correlated. Items were reasonably
related to their respective constitutions, with standardized factor loadings ranging from 0.307 to 0.793. Only 5 items had
loadings less than 0.4, suggesting that they were weaker items less related to their constitutions and required closer
examination in future CCMQ revisions. They were Q17 (Did the palms of your hands or soles of your feet feel hot?),
Q38 (Did you get hot ashes?), Q30 [Did you have allergies (eg, medicine, food, odors, pollen, etc.?)], Q31 (Did your
skin get hives/urticaria easily?), and Q13 (Did you experience distention in the underarm or breast?).
Overall Appropriateness of the 9-Constitutions Structure—Model Fit
The assessment of the overall 9 constitution structures with conrmatory factor analysis showed that Phlegm-dampness
(Factor 4, F4) was extremely highly correlated with the Damp-heat constitution (F5), resulting in an improper
(mathematically nonpositive denite) solution. This suggested that Phlegm-dampness and Damp-heat cannot be effec-
tively differentiated from the present set of items. Consequently, they were grouped as a new Dampness factor (a second-
order factor F10). Furthermore, some of these clinical observations (the 53 items) in the same or different constitutions
were very similar and strongly related (see next section; correlated uniquenesses in the conrmatory factor analysis
terminology). The overall t of the 53 items to the eventual model was acceptable; various indices of model t were χ
2
(1263) = 4516.27, RMSEA = 0.040 (90% CI, 0.039–0.042), Prob. (RMSEA ≤.05) = 1.000, CFI = 0.90, TLI = 0.89. Using
the criteria generally adopted,
41,42
the t indices reafrmed that the data collected t the originally intended 9-constitu-
tion structure reasonably well.
Items (Clinical Observations) Related to More Than One Constitution (Correlated
Items)
As discussed above, it was reasonable to postulate before assessing the model t that some clinical observations (the
items) in the same or different constitutions captured similar clinical characteristics and were thus highly correlated. For
example, Q24 (Did you sneeze even when you did not have a cold?) and Q25 (Did you have a runny or stuffy nose even
when you did not have a cold?), both in the Inherited Special constitution (F7), were strongly related (standardized
correlated uniqueness = 0.39). This showed that Q24 and Q25 had commonality over and above (statistically a correlated
uniqueness) that captured by their common Inherited Special constitution (F7). Similarly, Q31 and Q30 (both in F7;
correlated uniqueness = 0.20) and Q39 and Q41 (both in F5, correlated uniqueness = 0.20) had similarly substantial
correlations. As these item pairs came from the same constitutions, one of the two items can be removed, or the two
items can be combined in future CCMQ revisions.
There were also pairs of clinical observations coming from two different constitutions. They included, for example,
Q20 (F1) and Q22 (F9; correlated uniqueness = 0.37); Q39 (F5) and Q28 (F4; 0.33); Q57 (F2) and Q56 (F5; 0.21); Q22
(F9) and Q19 (F1; 0.23); Q48 (F5) and Q46 (F2; 0.20); and Q51 (F4) and Q47 (F7; 0.20), which came from two
constitutions and were correlated. For these item pairs from different constitutions, (i) one or both items in the item pair
can be revised so that they focus on one constitution only, or (ii) one or both items in the item pair can be removed if they
have double and confusing meanings.
Relations Among Constitutions
The correlations among the constitutions (Table 3) showed moderate to strong relations, supporting their commonality in
measuring the individuals’ TCM body characteristics. It was also noted that the Balanced constitution (F9) was
negatively correlated with all other scales, which suggested it was measuring body constitution from an opposite
perspective to those of the other eight constitutions. In general, it was understandable that the Phlegm-dampness
constitution (F4) and Damp-heat constitution (F5), both measuring “dampness”, were highly correlated. Similarly, the
https://doi.org/10.2147/PPA.S373512
DovePress
Patient Preference and Adherence 2022:16
1880
Lu et al Dovepress
Powered by TCPDF (www.tcpdf.org)

Yang-decient constitution (F1), Yin-decient constitution (F2), and Qi-decient constitution (F3) were also moderately
to highly correlated, measuring “deciency”. The Stagnant Qi constitution (F8) and Balanced constitution (F9) were
closely but negatively related. The Stagnant Blood constitution (F6) and Inherited Special constitution (F7) were two
constitutions much less associated with the remaining constitutions (F1, F2, F3, F4, F5, F8, F9).
Discussion
The quality and usefulness of the CCMQ were assessed comprehensively from a wide range of psychometric properties.
Specically, (a) the reliability of each constitution was reasonably high (0.638–0.831), (b) most item-constitution
relations (ie, factor loading) were high, and ve items with weaker loadings were identied, and (c) conrmatory factor
analysis showed good t of data to the model, broadly supporting the appropriateness of the clinical observations (the
questionnaire items) as measures of their intended 9 constitutions. That is, the CCMQ instrument successfully captured
the general construct of Chinese body constitutions, while the 9 (eventually combined into 8) separate scales also
appropriately differentiated the body constitutions.
At this juncture, we would like to point out that our ndings on the performance of CCMQ constitutions and items
have direct implications on CTM clinical diagnosis, prognosis, and treatment in general. Thus, for example, our results
showed that the Phlegm-dampness and Damp-heat scales were highly correlated. This suggested that in clinical
assessment and treatment, clinicians would nd great difculties in differentiating these two constitutions. Clinicians
and instrument developers must identify new items to better differentiate these two constitutions. Similarly, for the weak
items we identied below, clinicians are also alerted that clinical observations on these symptoms may have to be
adjusted accordingly (see Table 4).
Based on the reliability analyses, 7 items (Q1, Q7, Q29, Q32, Q33, Q36, and Q53) were removed from this study.
In a previous study,
43
these items (except Q29) were also deleted based on their psychometric properties (eg,
Cronbach’s alpha, item response theory) and expert panel opinion (face validity). The results and recommendations
in this study were, therefore, generally consistent with a previous study.
43
Contentwise, Q29 (Were your lips redder
than others?) in the Yin-decient constitution (F2) seemed essential for identifying the Yin-decient constitution.
While it is true that some people’s lips with Yin-decient constitution might be redder than others, it is also possible
that some people with Damp-heat constitution might also have similar characteristics. Such items may not discrimi-
nate well in the identication of the constitution. It could be one of the potential items, therefore, for deletion in future
CCMQ revisions.
This study showed that 5 items (Q13, Q17, Q30, Q31, and Q38) were weaker measures of their respective
constitutions (loading less than 0.4). In previous studies,
43,44
Q38 and Q31 were also recommended to be removed
based on psychometric properties and expert panel opinion (face validity). Relatively, Q17, Q30, and Q13 also had
weaker relations with their constitutions. However, they appeared to be important indicators in body constitution
identication in clinical diagnosis and can be retained. Nevertheless, these items can still be revisited and polished in
Table 3 Correlations Among the Constitutions Scores*
F1 F2 F3 F4 F5 F6 F7 F8 F9
F1 (Yang-decient) 1
F2 (Yin-decient) 0.607 1
F3 (Qi-decient) 0.611 0.650 1
F4 (Phlegm-dampness) 0.500 0.682 0.579 1
F5 (Damp-heat) 0.507 0.711 0.542 0.725 1
F6 (Stagnant Blood) 0.482 0.597 0.489 0.528 0.560 1
F7 (Inherited Special) 0.498 0.576 0.582 0.572 0.520 0.460 1
F8 (Stagnant qi) 0.579 0.641 0.681 0.560 0.533 0.514 0.491 1
F9 (Balanced) −0.663 −0.648 −0.738 −0.563 −0.533 −0.555 −0.529 −0.713 1
Note: *Based on a weighted sample balanced on gender and age.
Patient Preference and Adherence 2022:16 https://doi.org/10.2147/PPA.S373512
DovePress
1881
Dovepress Lu et al
Powered by TCPDF (www.tcpdf.org)

future CCMQ revisions. For example, in Q17, “Do the palms of your hands or soles of your feet feel hot?”, some people
might have hot palms but cold soles (rather than both hot) and would have difculty answering this item. Importantly,
this study helped identify items that should be carefully examined and further polished.
Although the study started with a 9-constitution structure, the results suggested that some constitutions (eg, Phlegm-
dampness constitution, Damp-heat constitution) were highly correlated and hard to differentiate by the participants using
the present set of items. Furthermore, the differentiation of other constitutions can also be revisited and improved. For
example, high correlations were observed between Q24 and Q25, Q31 and Q30, and Q39 and Q41. These results
suggested that the items in these item pairs can be less discriminating, confusing, or similar for many patients. Notably,
again, this study identied items or item pairs that can be revised or removed in future CCMQ revisions.
The conclusions drawn from the present study were limited by the participants being recruited from three villages in
southern China. Future replications with participants from other geographic regions in China or other countries would
provide information on how generalizable the results in this study are for future CCMQ revisions.
Conclusions
In this study, the items and structure of a popular TCM body constitution questionnaire were carefully assessed with
a sufciently large sample size of healthy participants. Generally, the results showed that the CCMQ had reasonably good
reliability, differentiating constitution structure, and construct validity to support its use as a valid and convenient
Chinese body constitution assessment instrument. Nonetheless, through the analyses of its reliabilities, correlations of
items to their respective constitutions, relations among the constitutions, and correlations among item pairs, various
issues with the items or constitutions have been identied to facilitate future CCMQ revisions or enhancements. This
agrees with the CCMQ’s original authors’ recommendation that accumulated experience would help our timely revisions
of the original instruments.
34
Indirectly, this study also provided an exemplary practical approach based on advanced
Table 4 Summary of Findings and Implications to Clinicians and Instrument Construction
Findings and Implications
A. Items/symptoms unrelated to their original constitution or other constitutions, recommend not to use
Q1 (energetic), Q7 (weak when talk), Q29 (red lips), Q32 (purpura allergy), Q33 (black/purple bruises), Q36 (visible capillary), Q53 (adapt
external environment)
B. Items/symptoms low relations with original constitutions, recommend to revise
Q17 (Palms/Hands/Feet sole hot, Yin-decient), Q38 (hot ashes, Yin-decient), Q30 (allergies, Inherited), Q31 (skin hivers/urticaria, Inherited
Special), Q13 (distention underarm/breast, Stagnant Qi)
C. Item-pairs/symptom-pairs, highly correlated within the same constitutions, duplicating indicators with similar meaning,
perhaps ask one in the pairs only
Q24 (sneeze without have a cold?) + Q25 (runny/stuffy nose without cold) in Inherited Special
Q31 (skin hives/urticaria) + Q30 (allergy) in Inherited Special
Q39 (greasy nose/face) + Q41 (acne, sores) Damp-heat
D. Item-pairs/symptom-pairs, highly correlated, they came from two constitutions, double meaning; recommend to revise the
items/symptoms so that they focus on one constitution only
Q20 (sensitive to cold, Yang-decient) + Q22 (vulnerable to cold, Balanced)
Q39 (nose/face greasy, Damp-heat) + Q28 (oily forehead, Phlegm-damp)
Q57 (constipate, Yin-decient) + Q56 (sticky stools, Damp)
Q22 (vulnerable to cold, Balanced) + Q19 (cold abdomen, back, Yang-decient)
Q48 (bitter mouth, Damp-heat) + Q46 (parched, need water, Yin-decient)
Q51 (phlegm, Phlegm-damp) and Q47 (throat strange, Inherited Special)
E. Highly correlated constitutions, hard to differentiate, may need more new symptoms to differentiate these two constitutions
Phlegm-dampness + Damp-heat constitution
F. Not all constitutions are positively related, handle with care
Balanced Constitution negatively related to all other constitutions, it measured body constitutions from an opposite perspective to those of
other 8 constitutions
https://doi.org/10.2147/PPA.S373512
DovePress
Patient Preference and Adherence 2022:16
1882
Lu et al Dovepress
Powered by TCPDF (www.tcpdf.org)

methodologies used in psychology and other social sciences to analyze and rene the CCMQ and other TCM
questionnaires. Our results have similar critical applications for CTM clinicians using various symptoms as measures
of Chinese constitutions in assessment, treatment, and health promotion (see Table 4).
Acknowledgments
We would like to thank all the participants from the three villages, namely, Shilian Village, Xiangang Village, and
Songtang Village. We also extend our thanks to all the staff and the village heads for their support and work, especially
Dr. Xiaoming Ma from the 8th People’s Hospital of Nanhai District, Foshan, Guangdong, Dr. Weitong from the Fourth
People’s Hospital of Nanhai District, Foshan, Guangdong, and Dr. Peixia Lu from Xiqiao Town Community Health
Service Center of Nanhai District, Foshan, Guangdong.
Funding
This study was funded by the National Key R&D Program of China (No.2019YFC1709800/ No. 2019YFC1709802); the
State Key Laboratory of Dampness Syndrome of Chinese Medicine (No.SZ2021ZZ03/No.SZ2021ZZ0302/No.
SZ2021ZZ30/No.SZ2020ZZ10/No.SZ2020ZZ09/ No.SZ2021ZZ32); the Guangdong Provincial Key Laboratory of
Clinical Research on Traditional Chinese Medicine Syndrome (No. ZH2019ZZ04); the Science and Technology
Planning Project of Guangdong Province (No. 2017B030314166). The funders did not participate in the design, data
collection, management, analysis, approval of the manuscript, and decision to submit the manuscript for publication.
Disclosure
The authors declare that they have no competing interests in this work.
References
1. Wang Q. Constitution of Traditional Chinese Medicine. 2nd ed. Beijing: People’s Medical Publishing House; 2005:2.
2. Wang Q. The Discovery of Nine Constitutions of Chinese People. Beijing: Science Press; 2011:8–9.
3. Yang XG, Li XZ, Ren Y, et al. Classication of traditional Chinese medicine constitution and questionnaire: application and research. Chin J of
Integr Trad & West Med. 2017;37(8):1003–1007.
4. Zhang C. Modern research progress in TCM constitution identication. Chin J Informat TCM. 2000;27(9):1–4.
5. Brien KA, Abbas E, Zhang J, et al. An investigation into the reliability of Chinese medicine diagnosis according to eight guiding principles and
Zang-Fu theory in Australians with hypercholesterolemia. J Altern Complement Med. 2009;15(3):259–266. doi:10.1089/acm.2008.0204
6. Brien KA, Abbas E, Zhang J, et al. Understanding the reliability of diagnostic variables in a Chinese medicine examination. J Altern Complement
Med. 2009;15(7):727–734. doi:10.1089/acm.2008.0554
7. Schnyer RN, Conboy LA, Jacobson E, et al. Development of a Chinese medicine assessment measure: an interdisciplinary approach using the
Delphi method. J Altern Complement Med. 2005;11(6):1005–1013. doi:10.1089/acm.2005.11.1005
8. Langevin HM, Badger GJ, Povolny BK, et al. Yin scores and Yang scores: a new method for quantitative diagnostic evaluation in Traditional
Chinese Medicine Research. J Altern Complement Med. 2004;10(2):389–395. doi:10.1089/107555304323062392
9. Mist S, Ritenbaugh C, Aickin M. Effects of questionnaire-based diagnosis and training on inter-rater reliability among practitioners of traditional
Chinese medicine. J Altern Complement Med. 2009;15(7):703–709. doi:10.1089/acm.2008.0488
10. Brien KA, Birch S. A review of the reliability of traditional East Asian medicine diagnoses. J Altern Complement Med. 2009;15(4):353–366.
doi:10.1089/acm.2008.0455
11. Ryu H, Lee H, Kim H, Kim J. Reliability and validity of a cold-heat pattern questionnaire for traditional Chinese medicine. J Altern Complement
Med. 2010;16(6):663–667. doi:10.1089/acm.2009.0331
12. Park YJ, Park JS, Kim MY, et al. Development of a valid and reliable phlegm pattern questionnaire. J Altern Complement Med. 2010;17
(9):851–858. doi:10.1089/acm.2010.0504
13. Lin JD, Chen LL, Lin JS, et al. BCQ-: a body constitution questionnaire to assess Yin-Xu. Part I: establishment of a provisional version through
a Delphi process. Forsch Komplementmed. 2012;19(5):234–241. doi:10.1159/000343580
14. Lin JS, Chen LL, Lin JD, et al. BCQ-: a body constitution questionnaire to assess Yin-Xu. Part II: evaluation of reliability and validity. Forsch
Komplementmed. 2012;19(6):285–292.
15. Lin JD, Lin JS, Chen LL, et al. BCQs: a body constitution questionnaire to assess stasis in traditional Chinese medicine. Eur J Integr Med. 2012;4
(4):e379–e391. doi:10.1016/j.eujim.2012.05.001
16. Zheng SS, Li JX, Wang YL, et al. Study on TCM syndrome elements identication scale for chronic gastritis. China Medical Herald. 2018;15
(18):120–123.
17. Su YC, Chen LL, Lin JD, et al. BCQ+: a body constitution questionnaire to assess Yang-Xu. Part I: establishment of a rst nal version through
a Delphi process. Forsch Komplementmed. 2008;15(6):327–334. doi:10.1159/000175938
18. Wang Q. The foundation of the classication and diagnosis standards for the constitutions of TCM. Chin Standardization. 2009;32:16–26.
19. Wang Q, Zhu YB, Xue HS, et al. Primary compiling of Constitution in Chinese Medicine Questionnaire. Chin J Clin Rehabil. 2006;10(3):12–14.
20. Wang Q. Classication and diagnosis basis of nine basic constitutions in Chinese medicine. J Beijing Univ Tradit Chin Med. 2005;28(4):1–8.
Patient Preference and Adherence 2022:16 https://doi.org/10.2147/PPA.S373512
DovePress
1883
Dovepress Lu et al
Powered by TCPDF (www.tcpdf.org)

21. Jing HR, Wang J, Wang Q, et al. Applying Constitution in Chinese Medicine Questionnaire (English version) to survey TCM constitutions of the
American and Canadian Caucasian in Beijing. Chin J Tradit Chin Med Pharm. 2012;27(9):2417–2419.
22. Li BM, Cao HJ, Tian EH, et al. A cross-sectional study of a Korean population using The Standardized Constitution in Chinese Medicine
Questionnaire (Korean Version). J Anhui Univ Chin Med. 2015;34(4):25–28.
23. Zhu YB, Origasa H, Uebaba K, et al. Development and validation of the Japanese version of the Constitution in Chinese Medicine Questionnaire
(CCMQ). Kampo Med. 2008;59(6):783–792. doi:10.3937/kampomed.59.783
24. Zhu YB, Wang Q, Xue HS, et al. Preliminary assessment on performance of Constitution in Chinese Medicine Questionnaire. Chin J Clin Rehabil.
2006;10(3):15–17.
25. Zhu YB, Wang Q, Hideki O. Evaluation on reliability and validity of the Constitution in Chinese Medicine Questionnaire (CCMQ). Chin J Behav
Med Sci. 2007;16(7):651–654.
26. Yeh MH, Chao CH, Koo M, et al. Association of traditional Chinese medicine body constitution and moderate-to-severe cancer-related fatigue in
cancer patients. Complement Ther Med. 2019;43:44–48. doi:10.1016/j.ctim.2019.01.004
27. Tang YC, Zhao T, Huang N, et al. Identication of traditional Chinese medicine constitutions and physiological indexes risk factors in metabolic
syndrome: a data mining approach. Evid Based Complement Alternat Med. 2019;2019:1686205. doi:10.1155/2019/1686205
28. Kanazawa S, Zhu YB, Wang Q. Correlation between Chinese medicine constitution and skin types: a study on 187 Japanese women. Chin J Integr
Med. 2020;26(3):174–179. doi:10.1007/s11655-019-2709-3
29. Mou X, Zhou DY, Liu WH, et al. Study on the relationship between Chinese medicine constitutive susceptibility and diversity of syndrome in
diabetic nephropathy. Chin J Integr Med. 2013;19(9):656–662. doi:10.1007/s11655-013-1411-0
30. Mou X, Liu WH, Zhou DY, et al. Association of Chinese medicine constitution susceptibility to diabetic nephropathy and transforming growth
factor-β1 (T869C) gene polymorphism. Chin J Integr Med. 2011;17(9):680–684. doi:10.1007/s11655-011-0845-5
31. Jing HR, Wang J, Wang Q. Preliminary compiling of English version of Constitution in Chinese Medicine Questionnaire. J Anhui Univ Chinese
Med. 2015;34(5):21–25.
32. Zhu YB, Shi HM, Yu XH. Comparison of the performance of three versions of constitution of Chinese medicine questionnaire for healthy
populations. Chin Gen Pract. 2019;22(35):4381–4387.
33. Zhu LB, Wang J, Zheng YF, et al. Bibliometrics analysis of traditional Chinese Medicine Constitution Scale from 2006 to 2016. Guangming
Zhongyi. 2018;33(20):2939–2944.
34. Zhu LB, Wang J, Li YS, et al. Discussion on revision of constitution in Chinese medicine questionnaire. J Anhui Univ Chinese Med. 2016;35
(4):6–9.
35. Li YS, Yang Y, Li LR, et al. Interpretation on the difcult problems in application of traditional Chinese Medicine Constitution Scale. J Tradit Chin
Med. 2015;56(10):844–846.
36. Xin H, Wu JK, Guo X, et al. Discussion on the problems of nine traditional Chinese medicine constitutional types scale in clinical application. Chin
J Tradit Chin Med Pharm. 2014;29(6):1841–1843.
37. Zhu YB, Wang Q, Yu XH, et al. Construct validity and responsiveness of the 41- item short version of Constitution in Chinese Medicine
Questionnaire. Chin Gen Pract. 2017;20(26):3282–3286.
38. Wong W, Lam CL, Wong VT, et al. Validation of the Constitution in Chinese Medicine Questionnaire: does the traditional Chinese medicine
concept of body constitution exist? Evid Based Complement Alternat Med. 2013;2013:481–491. doi:10.1155/2013/481491
39. Marsh HW, Hau KT. Applications of latent-variable models in educational psychology: the need for methodological-substantive synergies.
Contemp Educ Psychol. 2007;32(1):151–170. doi:10.1016/j.cedpsych.2006.10.008
40. Muthén LK, Muthén BO. Mplus User’s Guide. 8th ed. Los Angeles (CA): Muthén & Muthén; 2017: 1998–2017.
41. Marsh HW, Balla JR, Hau KT. An evaluation of incremental t indexes: a clarication of mathematical and empirical properties. In:
Marcoulides GA, Schumacker RE, eds. Advanced Structural Equation Modeling Techniques. Mahwah (NJ): Lawrence Erlbaum; 1996: 315–353
42. Marsh HW, Hau KT, Wen ZL. In search of golden rules: comment on hypothesis testing approaches to setting cutoff values for t indexes and
dangers in over generalising Hu & Bentler (1999) ndings. Struct Equ Modeling. 2004;11:320–341. doi:10.1207/s15328007sem1103_2
43. Zhu YB, Yu XH, Wang Q, et al. Preliminary development and evaluation of the short- version Constitution in Chinese Medicine Questionnaire.
Chin Gen Pract. 2017;20(7):879–885.
44. Zhu YB, Wang Q, Shi HM, et al. Formulation and evaluation on short version of Chinese Medical Constitution Questionnaire with 30 items.
J Tradit Chin Med. 2018;59(18):1554–1559.
Patient Preference and Adherence Dovepress
Publish your work in this journal
Patient Preference and Adherence is an international, peer-reviewed, open access journal that focusing on the growing importance of patient
preference and adherence throughout the therapeutic continuum. Patient satisfaction, acceptability, quality of life, compliance, persistence and
their role in developing new therapeutic modalities and compounds to optimize clinical outcomes for existing disease states are major areas of
interest for the journal. This journal has been accepted for indexing on PubMed Central. The manuscript management system is completely
online and includes a very quick and fair peer-review system, which is all easy to use. Visit http://www.dovepress.com/testimonials.php to read
real quotes from published authors.
Submit your manuscript here: https://www.dovepress.com/patient-preference-and-adherence-journal
DovePress Patient Preference and Adherence 2022:16
1884
Lu et al Dovepress
Powered by TCPDF (www.tcpdf.org)