Download Assessment of oral health-related quality of life in Nigerian children

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K.A. Kolawole, O.D. Otuyemi, A.M. Oluwadaisi
Department of Child Dental Health
Faculty of Dentistry, Obafemi Awolowo University. Ile-Ife Nigeria
e-mail: [email protected]
Assessment of oral
health-related quality
of life in Nigerian children
using the Child
Perceptions
Questionnaire (CPQ 11-14)
ABSTRACT
Aim The study objective was to examine the impact of oral
health and disease on the quality of life of a population
sample of 11 to 14-year-old children in Ile-Ife, Nigeria using
the Child Perceptions Questionnaire (CPQ11-14). The
hypothesis was that children with more severe malocclusions
and greater caries experience would have higher CPQ scores
indicating worse quality of life.
Methods A random sample of school children were selected
to participate in this study. Two hundred and forty eight
children duly completed the CPQ11-14 and were examined
for malocclusion and dental caries using the Dental Aesthetic
Index (DAI) and DMFT index .
Results Overall CPQ 11-14 scores ranged from 0 to 81 with
a mean of 23.44 ± 17.19. There was no distinct gradient in
mean CPQ scores across the DAI categories of malocclusion.
Children with high caries experience according to the DMFT
also did not have higher CPQ scores. Significant correlations
were observed between the overall CPQ11-14 and domain
scores and global ratings of oral health and overall well-being.
No statistically significant associations were found between
the clinical and overall CPQ scores.
Conclusion The results indicate that the presence of
malocclusion and dental caries did not have a significant
impact on the quality of life of the Nigerian children using the
CPQ11-14. The CPQ11-14 may be unable to discriminate
between children in various malocclusion categories in all
population groups. The relationship of reported quality of life
and malocclusion is probably mediated by other factors.
Keywords: Children; Oral health; Quality of life.
Introduction
Psychologists, sociologists, orthodontists and other
dental researchers have sought the demonstration of an
association between malocclusion and psychosocial wellEUROPEAN JOURNAL
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being. The past few years have witnessed a great surge of
interest in the assessment of the social and psychological
impact of malocclusion. The goals of the investigators
include demonstrating the importance of dental aesthetics
in social and psychological life, as well as identifying the
specific features or traits that define the negative impact
of malocclusion [Cons et al.,1986].
Malocclusions are appreciable deviations from the ideal
that may be considered aesthetically and functionally
unsatisfactory [Houston and Tulley, 1986] i.e. those
irregularities of the teeth beyond the acceptable range of
normal. They are a reflection of the natural variations that
occur in any biological system. Physical appearance has
been found to have implications for an individual’s
psychological development [Stricker, 1980]. Malocclusions
can adversely affect an individual personal self-concept
and self-esteem not only during adolescence but also in
adulthood. Children with malocclusions are more likely to
be the victims of teasing, name calling and physical
bullying [DiBiase and Sandler, 2001]. Children who are
stigmatised or ridiculed by peers come to view themselves
as inadequate [Shaw et al., 1979].
An understanding of the physical, social and
psychological effects of malocclusion is important as it
provides an insight into the consequences of
malocclusion, i.e. the effects of malocclusion if left
untreated and the benefits of orthodontic care [O’Brien et
al., 1998; Cunningham and Hunt, 2001].
Although there is little agreement on the definition of
quality of life, it has been defined as a person’s sense of
well-being that stems from satisfaction or dissatisfaction
with the areas of life that are important to him/her [Becker
et al., 1993]. Health contributes to quality of life and the
true impact of health and disease on life is known as
health-related quality of life (HRQL). The purpose of a
HRQL instrument is not just to measure the presence and
severity of disease symptoms but also show the impact of
the illness and/or the intervention on the individual and in
some cases to study unmet patient needs [Bennett and
Phillips, 1999]
The Child Perceptions Questionnaire (CPQ11-14), was
developed by Jokovic et al. [2002] to produce a measure
that conforms to contemporary concepts of child health. It
has discriminative and evaluative properties and is
applicable to children with various dental and orofacial
disorders. It forms one component of the Child Oral
Health Quality of Life Questionnaire (COHQOL) which
consists of a parental caregiver perception Questionnaire,
a family impact Scale and three age-specific
questionnaires. It is a 37 item measure encompassing four
domains: oral symptoms, functional limitations, emotional
and social well-being.
The use of the CPQ11-14 among different populations
has shown that it is able to distinguish between individuals
and groups with poor and better OHRQoL [Foster Page,
2005; Brown and Al-Khayal, 2006].
The aim of this study was therefore to examine the
impact of oral health and disease on the quality of life of
a population sample of 11 to 14-year-old children in Ile- Ife
Nigeria using the CPQ11-14. The hypothesis was that
children with more severe malocclusions and greater caries
experience would have higher CPQ scores.
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KOLAWOLE K.A., OTUYEMI O.D. AND OLUWADAISI A.M.
Materials and methods
A sample of 252 children aged 11-14 years was
randomly selected from junior secondary schools in Ife
central Local government area of Osun state Nigeria, and
invited to participate in the study. The sample size was
determined as 184. A previous study by Jokovic et al.
[2002] gave a mean of 26.3 and a standard deviation of
16.7. Given an expected minimum difference of 8, a
power of 0.90 and a significance level of 0.05, a minimum
sample size of 184 subjects was needed. Ethical approval
was obtained from the Obafemi Awolowo University
Teaching Hospital Ethics Committee. Consent was
obtained from the appropriate school authority, the
children and their parents.
The CPQ 11-14 was administered in English and each
child completed it independently. The first two questions
on the CPQ 11-14 are the global ratings of the child’s oral
health and the extent to which the oral/orofacial condition
affected his/ her well-being, worded as follows. “Would
you say that the health of your teeth, lips and mouth is
…..” and “How much does the condition of your teeth
lips and jaws and mouth affect your life overall?” A 5point response format ranging from ‘Excellent’ = 0 to
‘poor’ = 4 and from ‘Not at all’ = 0 to ‘Very much’ = 4
respectively is offered for these ratings. The remaining
questions are organised into four health domains. Oral
symptoms (n = 6), functional limitations (n = 9) emotional
well-being (n = 9) and social well-being (n = 13). The
questions ask about the frequency of events in the
previous three months in relation to the child’s
oral/orofacial condition. The response options are ‘Never’
= 0, ‘Once/twice’ =1; ‘Sometimes’ = 2; ‘Often’ = 3;
‘Everyday/ almost every day’ = 4. An overall CPQ11-14
score was computed by addition of scores for all items in
the domains. Scores for each domain were also computed.
Dental examination was done by one examiner (KAK).
None of the selected children had undergone or was
undergoing orthodontic treatment. Examination for dental
caries was done using the World Health Organization
(WHO) criteria [1997]. The total number of decayed,
missing and filled teeth (DMFT) was determined for each
child, followed by an orthodontic examination.
Orthodontic assessment was based on the Dental
Aesthetic Index (DAI) [Cons et al., 1986]. The DAI is an
index designed specifically to measure dental aesthetics,
which has the ability to recognise conditions that deviate
from societal accepted norms for dental appearance and
have the potential for causing a psychosocial handicap.
The theoretical concept underlying the DAI predicts that
the more a person’s dental appearance deviates from
excellent the more likely it is that the person will
experience social handicaps and therefore request
orthodontic treatment. The WHO, in order to address the
issue of non-uniformity in methods for assessing
malocclusion, incorporated a description of the DAI in its
7th edition of Basic Methods for Oral Health Surveys
[1997]. The DAI consists of 10 components. Scores for
each occlusal trait were determined by direct
measurement. The multiplication of these scores by the
weighting factor, summation of these products, and the
addition of a constant produced the total DAI score. The
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scores were used to categorise the children into 4 groups:
a) no/slight treatment need;
b) treatment need;
c) treatment highly desirable;
d) treatment mandatory.
Data entry and analysis were done on an IBMcompatible personal computer. The SPSS version 11.0 was
used to determine the range, mean DAI score, total CPQ
and domain scores. ANOVA was used to compare the
mean CPQ scores of the children in various malocclusion
well-being groups. The relationship between the global
ratings on oral health and well-being and the overall CPQ
score were determined using correlation coefficient tests.
The association between the DMF and DAI scores and the
overall CPQ and domain scores were also determined
using correlations.
Results
Of the 252 school children sampled in this study, 248
questionnaires were complete enough for analysis.
Incomplete questionnaires were excluded. There were 126
female and 122 male participants. The mean age was
12.54 ± 1.08 (Table 1).
Scores for the CPQ 11-14 ranged from 0 to 81. There
were three participants with floor effects, i.e. a score of
zero, but none with ceiling effect, i.e. maximum score. The
mean score was 23.44 ± 17.19. The mean for male and
female were 22.70 and 24.17 respectively (Table 2, 3).
There was no significant difference between them. The
mean score was higher for the females in all domains
except the emotional wellbeing domain, which was not
statistically significant. About 72.5% of the children
reported experiencing oral symptoms in the past three
months, 56.9% functional limitations, 63.3% reported
emotional and 65.3% social impacts.
The mean DAI score was 26.39. The scores were 26.51
Male
Female
Total
Number (%)
Mean age (SD)
122 (49.2)
12.49 (1.09)
126 (50.8)
12.59 (1.07)
248 (100)
12.54 (1.082)
Malocclusion
Mean DAI score
26.51 (6.75)
26.27 (6.60)
26.39 (6.66)
Treatment need
Number (%)
Minor/none
Definite
Severe
Handicapping
63 (51.6)
31 (25.4)
18 (14.8)
10 (8.2)
70 (55.6)
28 (22.2)
12 (9.5)
16 (12.7)
133 (53.6)
59 (23.8)
30 (12.1)
26 (10.5)
Dental caries
Number (%)
DMFT = 0
DMFT = 1
DMFT = 2
113 (92.6)
6 (4.9)
3 (2.5)
118 (93.7)
8 (6.3)
0 (0)
231 (93.1)
14 (5.7)
3 (1.2)
TABLE 1 - Percentage distribution by sex, categories of
malocclusion and caries severity.
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Total scale
Subscales
Oral symptoms
Functional limitations
Emotional well-being
Social well-being
Number
of items
Mean score
Mean (SD)*
Range of observed
scores
37
23.44 (17.19)
0-81
6
9
9
13
5.27 (3.66)
4.77 (4.74)
6.30 (6.01)
7.10 (6.73)
0-18
0-24
0-28
0-27
TABLE 2 - Descriptive data
on CPQ and subscales.
*Standard deviation
Mean Overall CPQ score Mean CPQ Domain Scores
Oral symptoms Functional limitations
Sex
Mean (S.D)
Male
22.70 (15.33)
Female
24.17 (18.85)
Dental caries category
Mean (S.D)
DMFT = 0
23.55 (17.24)
DMFT = 1
18.57 (13.12)
DMFT = 2
38.00 (26.22)
p value
0.194
Malocclusion category (DAI) Mean (S.D)
Minor
25.11(18.65)
Definite
20.19 (14.53)
Severe
20.47(14.02)
Handicapping
25.77 (17.56)
p value
0.192
Emotional Well-being Social Well-being
5.07 (3.39)
5.46 (3.90)
4.57 (4.62)
4.97 (4.82)
6.34(5.63)
6.27(6.39)
6.72 (6.14)
7.47 (7.26)
5.25 (3.70)
5.21 (3.19)
6.00 (3.61)
0.941
4.70 (4.70)
4.36 (3.63)
12.33(7.77)
0.020
6.43(6.09)
3.64(3.69)
9.00(6.93)
0.179
7.16 (6.70)
5.36 (6.71)
10.67(9.87)
0.408
5.65 (3.81)
4.47(3.44)
4.53(3.09)
6.00(3.69)
0.091
5.12 (5.17)
4.29 (4.34)
3.90 (3.38)
5.08 (4.66)
0.486
6.37(6.15)
5.95(6.04)
5.80(5.31)
7.35(6.19)
0.752
7.97(7.33)
5.47(5.93)
6.23(5.61)
7.35(5.84)
0.102
TABLE 3 - Overall CPQ and Domain Mean scores by sex, caries severity and categories of malocclusion.
Total scale
Subscales
Oral symptoms
Functional limitations
Emotional well-being
Social well-being
GLOBAL RATING
Oral health
Overall well-being
SCORE
DAI
R
0.295
p value
0.000
R
0.444
p value
0.000
R
-0.019
p value
0.760
R
-0.022
p value
0.729
0.319
0.266
0.291
0.162
0.000
0.000
0.000
0.011
0.490
0.386
0.352
0.282
0.000
0.000
0.000
0.000
-0.060
-0.025
0.062
-0.064
0.346
0.691
0.334
0.313
0.018
0.062
-0.070
-0.036
0.775
0.329
0.271
0.575
R=Spearman’s correlation coefficient
and 26.27 for male and female respectively (Table 1). The
difference was not significant. There was also no
significant gender difference in the distribution into
treatment categories according to the DAI. There was no
distinct gradient in mean CPQ scores across the various
malocclusion categories according to the DAI. The highest
mean CPQ score was obtained in the treatment category
4, i.e. treatment mandatory group. The treatment group 1
that represented minor/no need for orthodontic treatment
had a mean score of 25.1. No gradient was observed in
the mean CPQ domain scores according to the DAI
treatment categories (Table 3). There was no significant
difference when the overall CPQ and domain scores in the
four malocclusion groups were compared.
Ninety three percent of the sample had no caries
experience and had a DMFT of 0, 5.7% had a DMFT of
1, while only 1.2% had a DMFT of 2 (Table 3). Although
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DMFT
TABLE 4 - Correlations
between overall CPQ and
Domain scores, global ratings
of oral health and overall
well-being and DAI and
DMFT scores.
the highest CPQ score was obtained in the DMFT= 2
group, there was no gradient as the second highest score
was obtained in the DMFT = 0 group (Table 3). There was
no significant difference in CPQ scores between the
DMFT groups except the functional limitation domain (p
= 0.02).
The relationship between overall CPQ score and global
ratings on oral health and well-being revealed significant
positive correlation (p =0.000). The correlation was
better for overall well-being (r = 0.44) than the oral
health rating (r = 0.29). Significant positive correlations
were also observed between the scores for all health
domains and global ratings of oral health and overall
well-being. No statistically significant associations were
found between the clinical and CPQ total scores (Table
4). The mean score for children reporting that their
overall well-being was “not at all” affected by their oral
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KOLAWOLE K.A., OTUYEMI O.D. AND OLUWADAISI A.M.
condition was 15.94 while for those reporting that it
affected “a lot or very much” it was 36.68.
Discussion
There is an increasing recognition that oral disorders
can have a significant impact on physical, social and
psychological well-being although conflicting evidence
exists [Zhang et al., 2006]. In relation to facial aesthetics
it has been shown from the point of view of the patient
that teeth were second in importance only to
background facial appearance [Lew, 1993]. The oral
health related quality of life measures have the potential
to provide an understanding of the consequences of
malocclusion if left untreated on the lives of individuals.
In this study the mean overall CPQ score was 23.4
similar to 24.2 obtained by Brown and Al-Khayal in Saudi
Arabia [2006] and 26.3 obtained in the original
validation of the questionnaire by Jokovic et al. [2002],
but quite different from the mean of 17.3 found in the
study by Foster Page et al. in New Zealand [2005]. Zhang
et al. [2008] found a mean of 20.5, which they
considered low for a sample of orthodontic patients and
suggested that despite needing orthodontic treatment, a
subject’s oral situation may have a modest impact on the
quality of life.
Unlike the studies in New Zealand, Canada and Saudi
Arabia, there was no distinct gradient in mean CPQ and
domain scores across the various categories of
malocclusion according to the DAI. Research has shown
that self-ratings of health items vary by race and
education [Krause and Jay, 1994], and that evaluation of
quality of life is also strongly influenced by the
characteristics of an individual and his or her standards
of reference [O’Connor, 2004]. The result of this study
implies that children in the worse treatment categories of
malocclusion according to the DAI did not have worse
OHRQoL than their counterparts who had minimal traits
of malocclusion. Agou et al. [2008] in a study among
Canadian children also could not conclusively state that
increased malocclusion severity produced a direct
increase in CPQ11-14 scores.
This may be due to a number of reasons. Many
orthodontic conditions are asymptomatic and relate to
aesthetics rather than features like pain and discomfort,
whereas pain is a common symptom that can impact
quality of life [Zhang et al., 2006]. Unawareness of
occlusal traits may also have been a factor. Various
psychological, social, and cultural variables are known to
be involved in an individual’s awareness of a
malocclusion. It is not every child with a malocclusion
that is self-conscious about it, there is considerable
variability of adjustment to the irregularity from total
unawareness to deep concern [Shaw, 1981]. While some
are unaware of pronounced malocclusion others may
show great concern over a relatively mild irregularity
[Gosney, 1986]. Unawareness may make it impossible for
deviant occlusal traits to affect the psychosocial wellbeing of an individual.
There is a possibility that the children were not able to
accurately perceive their dental appearance. Perception
58
of the aesthetic effects of malocclusions and the need
and desire for treatment vary greatly in individuals.
Accuracy of self-perception may even be particularly
poor for young individuals. Studies indicate that children
have limited ability to perceive their teeth accurately
[Graber and Lucker, 1980; Shaw, 1981; Lindsay and
Hodgkins, 1983; Holmes, 1992]. Previous studies have
shown that Nigerian children have a tendency for them
to overrate their dental appearance [Otuyemi et al.,
1997; Kolawole et al., 2008].
Research has found that the relationship between
reported OHRQoL and malocclusion is most likely
mediated by other factors [Marshman et al., 2005]. The
impact of oral conditions on individuals has been found
to depend on their sense of self. An individual’s sense of
self is based on how adequately they perform in the
domains of life that are important to them. Performance
in unimportant areas has little impact on the self
[Marshman et al., 2009]. For some their sense of self may
be contingent on appearance, while others may relate
importance to domains such as personality.
Dental appearance did not appear to have been an
important domain for these Nigerian children. This may
explain lack of significant difference between children
with “no malocclusion’’ and those with “severe”
malocclusion traits. Stricker [1970] and Gosney [1986]
had stated that the impact of dental appearance on the
body image and self-concept is greater in persons who
regard dental appearance as important than in those
who do not consider it so. In Nigeria, availability and
uptake of dental and orthodontic services is still very low.
Individuals with malocclusion traits which are considered
handicapping live their everyday lives without being
bothered about it. When dental appearance is even
regarded as important, other social pressures and the
impact of poverty on the lives of people in developing
countries like ours may not make oral health concerns a
priority. Not many people have access to orthodontic
care because it is expensive and unaffordable.
Orthodontic services are provided on the basis of fee for
service rendered even in government owned hospitals
[Otuyemi, 2001]. Only five of the teaching hospitals in
Nigeria provide orthodontic services.
There was also no observed gradient in CPQ scores
across the various DMFT groups. This may be due to the
low prevalence of caries among the group of children
studied: 93% had no caries experience, which is similar
to previous reports from Nigeria. Significant correlations
were observed between the global rating of oral health
and the total CPQ score and domain scores. This is similar
to the report by Brown and Al-Khayal [2006] in Saudi
Arabia but different from that by Jokovic et al. [2002] in
Canada. Significant correlations were also noted
between the global rating of overall well-being and the
total CPQ score and domain scores. This is similar to the
findings of Jokovic et al. [2002] and Brown and Al-Khayal
[2006]. There was however no association between
global rating of overall well-being and social well-being
in the latter study.
No statistically significant associations were found
between the clinical and CPQ total scores. This also
differs from the study by Brown and Al-Khayal [2006],
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although direct comparisons between our study and
theirs may not be possible because of the difference in
the method of assessment of malocclusion. In the UK
Marshman et al. [2005] were also not able to find any
association between DMFT and CPQ scores. Correlations
between DAI, DMFT scores and domain scores were also
not significant; this agrees with reports by Brown and AlKhayal [2006] who demonstrated a positive significant
correlation only between the DMFT and oral symptoms,
their malocclusion Index and social well-being.
Conclusion
The results of this study indicate that the presence of
malocclusion and dental caries did not have a significant
impact on the quality of life of the Nigerian children
using the CPQ11-14. The CPQ11-14 is valid but may be
unable to discriminate or distinguish between children
with various severities of malocclusion in all population
groups. Factors such as racial differences, characteristics
of the individual, education and standards of reference
may affect ratings of health items. Further studies in a
clinical setting among children requiring orthodontic
treatment may also be necessary.
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