The Vietnamese version of the health-related quality of life measure for children with epilepsy (cheqol-25): Reliability

MedPharmRes, 2017, 1 9
MedPharmRes
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Original article
The Vietnamese Version of the Health-related Quality of Life Measure for 
Children with Epilepsy (CHEQOL-25): Reliability
Doan Huu Tria, Tran Diep Tuanb*, Nguyen Bao Huu Hanb 
a The Center for Advanced Training in Clinical Simulation, University of Medicine and Pharmacy at Ho Chi Minh City, Vietnam; 
b Department of Pediatrics, University of Medicine and Pharmacy at Ho Chi Minh City, Vietnam.
Received August 25, 2017: Accepted September 24, 2017 Published online December 10, 2017
Abstract: Purpose: This study aimed to translate and culturally adapt the self-report and parent-proxy Health-Related 
Quality of Life Measure for Children with Epilepsy (CHEQOL-25) into Vietnamese and to evaluate their reliability. 
Methods: Both English versions of the self-report and parent-proxy CHEQOL-25 were translated and culturally 
adapted into Vietnamese by using the Principles of Good Practice for the Translation and Cultural Adaptation Process. 
The Vietnamese versions were scored by 77 epileptic patients, who aged 8–15 years, and their parents/caregivers at 
neurology outpatient clinic of Children Hospital No. 2 – Ho Chi Minh City. Reliability of the questionnaires was 
versions of the self-report and parent-proxy CHEQOL-25 were shown to be consistent with the English ones, easy to 
for each subscale of the Vietnamese version of the self-report and parent-proxy CHEQOL-25 was 0.65 to 0.86 and 
0.83 to 0.86, respectively. The ICC for each subscale of the self-report and parent-proxy CHEQOL-25 was in the 
range of 0.61 to 0.86 and 0.77 to 0.98, respectively. Conclusion: The Vietnamese version of the self-report and 
Vietnamese version was shown to be reliable to assess the quality of life of children with epilepsy aged 8–15 years.
Keywords: childhood epilepsy, quality of life, health-related quality of life, CHEQOL-25 instrument
1. INTRODUCTION
Epilepsy is a chronic disease affecting humans since 
ancient times and up to now, it remains as one of the 
diseases that causes the most severe disabilities. Epilepsy 
affects patients’ activities as well as their family for a long 
lives [1]. Children with epilepsy are often more affected 
psychologically and socially than children with asthma 
although both are chronic diseases [2]. This shows that such 
problems in children with epilepsy are not merely caused 
by their living with a chronic medical condition [3]. Current 
studies on epilepsy in the world in general and in Vietnam 
in particular mostly still revolves around such classic 
problems as pathophysiology or treatment effects without 
paying adequate attention to the patients’ quality of life [4, 
5]. Evaluation of epileptic patients’ lives provides important 
information related to treatment and helps to improve 
treatment quality [6]. 
In recent years, clinicians have paid more attention to 
the health-related quality of life (HrQOL) issue of patients 
with epilepsy and developed various instruments to assess 
this factor. There are many studies on how to measure 
HrQOL in adult and children with epilepsy in the world. 
Recently, measurements of HrQOL have been accepted 
to take not only a descriptive role but also instrument to 
and management of epilepsy in patients [7]. 
Quality of life, in general, is considered a social 
category, which is ruled by each country’s culture, tradition, 
and ideology. Therefore, results from the studies of other 
countries cannot absolutely apply to Vietnam society. 
In Vietnam today, there is still not a Vietnamese version 
of measurement of HrQOL in epileptic patients to be 
utilized locally. Among instruments have been developed 
* Address correspondence to this author at the Department of Pediatrics, 
University of Medicine and Pharmacy, 217 Hong Bang street, District 5, 
Ho Chi Minh City, Vietnam; E-mails: dieptuan@ump.edu.vn
© 2017 MedPharmRes
10 MedPharmRes, 2017, Vol. 1, No. 1 Doan et al.
and validated to assess the quality of life of children with 
epilepsy, the Quality-of-life Measure for Children with 
Epilepsy (CHEQOL-25) of Gabriel M. Ronen et al [8] have 
many advantages: (1) psychometric properties are fully 
proven, (2) both version for parent-proxy and self-report 
are available, (3) special structure with alternative paired 
options of forced responses that have been developed by 
Harter for “The Perceived Competence Scale for Children” 
help this instrument more appropriate, more feasible to 
administer and show less response bias than the traditional 
Likert scales [8]. This measurement has been translated and 
adapted into many languages in countries and territories 
such as Hong Kong [9, 10], Malaysia [11], etc. Therefore, 
we decided to translate and cross-culturally adapt this 
instrument into Vietnamese and assess the reliability of the 
translated ve ... tal correlation. Items with corrected 
item-total correlation from 0-0.19 may indicate that the 
question is not discriminating well, from 0.2-0.39 indicate 
good discrimination and greater than 0.4 indicate very good 
discrimination.
11The Vietnamese version of the health-related MedPharmRes, 2017, Vol. 1, No. 1
Test-retest reliability or reproducibility was analyzed 
The closer the ICC value is to 1.0, the better the test-retest 
reliability. ICC values > 0.75 indicate high reliability, from 
0.5-0.75 indicate medium reliability, and < 0.5 indicate 
low reliability [15]. Similar research accepted ICC value 
higher than 0.7 or 0.6 [8, 10]. In this research, we accepted 
a subscale with ICC higher than 0.6. 
ICC was also used to determine the level of agreement 
between parent-proxy and self-report version [12, 16]. 
moderate agreement, 0.61–0.80 as good agreement, and 
0.81–1.00 as excellent agreement [12]. 
3. RESULTS AND DISCUSSION
3.1. Results
inclusion criteria, 23 patients declined participation and 93 
Table 2. Characteristics of the sample
Characteristic N % (n = 77)
Type of parent
 Mother 33 63.5
 Father 14 26.9
 Other 5 9.6
Level of education of parents/caregiver
 Primary education 13 25.0
 Secondary education 18 34.6
 High school 18 34.6
 Undergraduate 3 5.8
 Graduate 0 0
Child’s Gender
 Male 40 51.9
 Female 37 48.1
Mean age of the child with epilepsy ± SD (years) [range] 10.67 ± 1.84 [8-14]
Seizure type
 Generalized tonic-clonic 40 51.9
 Partial 25 32.5
 Absence 6 7.8
 Others 6 7.8
Seizure frequency
 Almost daily 4 5.2
 Once a week or more frequently 5 6.5
 Several times a month 10 13.0
 Several times a year 17 22.1
 Not occurred 41 53.2
Number of antiepileptic drugs
 1 59 76.6
 2 14 18.2
4 5.20
SD = standard deviation
rate: 80.2%). In the second assessment four weeks later, 
there was 16 patients lost communication. Therefore, a 
total of 77 patients administered twice and included in this 
and the demographic as well as epilepsy characteristics of 
the sample were shown in Table 2.
Figure 1. Flow of participants
12
The descriptive statistics of Vietnamese version were shown in Table 3.
Table 3. Descriptive statistics of the CHEQOL-25 subscales for parents and children
Subscale
Mean (SD) Skewness (SE) Kurtosis (SE) Range
Parent Child Parent Child Parent Child Parent Child
Interpersonal/Social 12.97 
(4.08)
15.01 
(3.65)
-0.28 
(0.27)
-0.22 
(0.27)
-1.23 
(0.54)
-1.35 
(0.54)
6-19 9-20
Present worries 12.26 
(3.95)
11.44 
(3.54)
0.09 
(0.27)
0.29 
(0.27)
-1.14 
(0.54)
-0.58 
(0.54)
5-20 5-20
Future worries 13.42 
(3.79)
-0.27 
(0.27)
-1.25 
(0.54)
7-20
Intrapersonal/Emotional 10.75 
(3.28)
14.30 
(3.34)
0.00 
(0.27)
-0.70 
(0.27)
-1.02 
(0.54)
-0.13 
(0.54)
5-18 6-20
Epilepsy secrecy 10.96 
(3.90)
10.62 
(3.33)
0.54 
(0.27)
0.16 
(0.27)
-1.00 
(0.54)
-1.10 
(0.54)
5-19 6-17
Quest for normality 13.65 
(3.66)
0.46 
(0.27)
-1.13 
(0.54)
9-20
subscale was greater than 0.7. The subscale with the lowest 
(0.847). All items had a corrected item-total correlation 
value of > 0.2 (Table 4) 
In the self-report version, both the “Present Worries” and 
and 0.681, respectively, whereas, for the other scales, this 
correlation value of > 0.2 (Table 4).
Table 4.
Subscale
Parent-proxy Self-report
Item Corrected item-total correlation Item
Corrected item-total 
correlation 
Interpersonal/Social
1
2
3
4
5
0.661
0.641
0.696
0.682
0.338
0.847 1
2
3
4
5
0.699
0.589
0.602
0.625
0.581
0.883
Present worries
6
7
8
9
10
0.689
0.572
0.391
0.516
0.531
0.826 6
7
8
9
10
0.653
0.610
0.244
0.634
0.578
0.651
Future worries
11
12
13
14
15
0.698
0.540
0.572
0.644
0.633
0.844
Intrapersonal/Emotional
16
17
18
19
20
0.550
0.338
0.445
0.376
0.628
0.841 11
12
13
14
15
0.715
0.363
0.637
0.413
0.456
0.783
Epilepsy secrecy
21
22
23
24
25
0.606
0.616
0.494
0.573
0.573
0.862 16
17
18
19
20
0.563
0.648
0.367
0.438
0.524
0.681
Quest for normality
21
22
23
24
25
0.711
0.590
0.496
0.640
0.694
0.873
MedPharmRes, 2017, Vol. 1, No. 1 Doan et al.
13
Table 5.
Subscale
Parent-proxy Self-report
ICC p ICC p
Interpersonal/Social 0.98 < 0.001 0.76 < 0.001
Present worries 0.86 < 0.001 0.80 < 0.001
Future worries 0.77 < 0.001
Intrapersonal/Emotional 0.86 < 0.001 0.61 < 0.001
Epilepsy secrecy 0.87 < 0.001 0.86 < 0.001
Quest for normality 0.67 < 0.001
Regarding the test-retest reliability, Table 5 shows that 
the ICC for each subscale of the parent-proxy and self-report 
CHEQOL-25 was in the range of 0.77 to 0.98 and 0.61 to 
for all subscales of each version.
Moreover, with ICC between parent-proxy and self-
report version ranging from 0.35 to 0.62, most of the 
subscales had an acceptable level of agreement in the rating 
HrQOL of patients and their parents/caregivers, except for 
“Intrapersonal /Emotional” subscale (Table 6).
Table 6. ICCs between parent and child on the CHEQOL-25 
subscales
Subscale ICC p
Interpersonal/Social 0.62 < 0.001
Present worries 0.66 < 0.001
Intrapersonal/Emotional 0.35 0.001
Epilepsy secrecy 0.44 < 0.001
3.2. Discussion
In this research, the Vietnamese translation of the 
CHEQOL-25 was performed according to international 
guidelines [13]. Backward translation review for 
Vietnamese versions of CHEQOL-25 measurement was 
performed by Professor Gabriel M. Ronen of McMaster 
on 5 patients to assess comprehensibility, clarity, and 
appropriateness of each item. The content of each item was 
familiar with Vietnamese people so no changes necessary. 
The questions’ structure with Harter’s format was special 
and uncommon to most research participants. However, 
remaining questions were completed without any problem. 
This indicated our Vietnamese version measurement reaches 
semantic and content equivalence to the original version.
3.2.1. Reliability of parent-proxy CHEQOL-25
values > 0.7, which indicate that all subscales had very good 
internal consistency. The higher Cronbach’s alpha showed 
the higher correlation between items on the subscale, and 
hence the internal consistency was also higher. The lowest 
(0.826). The previous translation and cultural adaptation 
research of the CHEQOL-25 also showed that “Present 
remaining subscales: 0.72 in the Chinese version of Yam [9], 
0.44 in Serbian version of Stevanovic [16] and 0.67 in the 
Malay version of Wo [11]. According to Wo et al., the reason 
lead to this may be because the subscale widely assessed 
many different worries of the child, such as “think about 
their epilepsy before doing things” (item 6), “their parents 
are worried that they will hurt themselves” (item 7), “may 
not be able to go away to camp or similar places” (item 8), 
and “worry about getting hurt during a seizure” (item 10). 
Therefore, the internal consistency of this subscale was not 
as good as another subscale [11]. The corrected item-total 
correlation values of all items were > 0.2 which indicate 
Regarding the test-retest reliability, our data showed that 
0.6. The result revealed that the score of a parent-proxy version 
of Vietnamese CHEQOL-25 was stable in 4-week interval. 
3.2.2 Reliability of self-report CHEQOL-25
We found that the subscales of self-report version did 
not achieve a good reliability like the parent-proxy one. The 
“Present worries” and “Epilepsy secrecy” subscale had the 
This was identical with previous research. In the original 
of these subscales were 0.71 and 0.63, respectively [8]. In 
the Serbian version of Stevanovic, the internal consistency 
uncorrelated item may not be covered by the remaining 
items. Elimination of some questions to elevate the value of 
In addition, similar to parent-proxy version, the corrected 
item-total correlation value of most items was> 0.4. The 
lowest corrected item-total correlation was also greater 
than 0.2. This indicated that the discrimination of all items 
in the self-report version was good to very good. Hence, 
we decided to keep all items in the Vietnamese self-report 
version like original instruments. 
Test-retest reliability analysis revealed that the child 
self-report version showed good reproducibility with ICCs 
of all subscales were greater than 0.6. The “Interpersonal/
Social”, “Present worries” and “Epilepsy secrecy” subscale 
were most stable and concrete with highest ICC (0.76, 0.80 
and 0.86, respectively). For both the “Intrapersonal/Emo-
tional” and “Quest for normality” subscales, the ICC was 
condition greater than 0.6 of an acceptable subscale. This 
result was similar to that of the English version of Ronen 
The Vietnamese version of the health-related MedPharmRes, 2017, Vol. 1, No. 1
14 MedPharmRes, 2017, Vol. 1, No. 1 Doan et al.
et al. with the ICC of these subscales were 0.63 and 0.65, 
respectively.
3.2.3 Agreement of parent-proxy and child self-report 
CHEQOL-25
Our data showed that there was an acceptable level 
of agreement between parent-proxy version and the child 
self-report version with most of ICCs ranging from 0.44 to 
0.66, which indicate moderate to good agreement, except for 
the “Intrapersonal/Emotional” subscale. The “Interperson-
al/Social” and “Present worries” subscale had the highest 
agreement with ICCs value were 0.62 and 0.66, respective-
ly. Meanwhile, the “Intrapersonal/Emotional” and “Epilep-
sy secrecy” subscales had a higher degree of discrepancy. 
This difference might be explained by the literature which 
suggests that emotion are harder observed than physical 
performance, hence good agreement is usually obtained 
between parent and child when assess physical aspects of 
HrQOL [12]. Despite the differences between perspectives 
of parent and child, the aforementioned result of ICCs indi-
cated that Vietnamese parent form of CHEQOL-25 could be 
used as proxy measure for HrQOL of children with epilepsy 
in connection with the child self-report version or when the 
self-report version could not be administered.
3.2.4 Limitations
Our research had some limitations. The sample size was 
small, factor analysis was not conducted to assess construct 
validity, and no other HrQOL Vietnamese measurement was 
available to test validity. Therefore, when another Vietnam-
ese measurement of HrQOL for children with epilepsy is 
available, we need to do this research again with a larger 
sample size to assess fully validity of Vietnamese versions 
of CHEQOL-25.
4. CONCLUSION
In summary, we translated and cross-culturally adapted 
the CHEQOL-25 instrument into Vietnamese with both 
versions for parent and child scoring. This research reported 
that our Vietnamese versions were easy to comprehend, 
feasible to administer, and equivalent to the original version 
of semantic and content. Both parent-proxy and self-report 
version had adequate good at internal consistency and test-
retest reliability to assess HrQOL in Vietnamese children 
with epilepsy. 
ACKNOWLEDGEMENTS
We would like to thank all the children and their par-
ents who participated in this study. We are grateful to all the 
physicians and nurses of Neurology Department of Children 
Hospital No. 2 – Ho Chi Minh City for their assistance. We 
thank Dr. Gabriel M. Ronen in assisting us in translating 
the instrument. The use of the Health-related Quality of 
Life Questionnaire in Children with Epilepsy, authored 
by Dr. Gabriel Ronen et al., was made under license from 
McMaster University, Hamilton, Canada.
CONFLICT OF INTEREST
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