Background
Pain problems among children and adolescents are a serious health concern, and studies show that 15–35% of children in a nonclinical population experience a persistent or chronic pain condition [
1‐
3]. The prevalence of pain increases with age, and older children report more pain than do younger children. Headache is the most commonly reported pain, followed by neck and shoulder pain, abdominal pain, backache, and limb pain, and several children report pain in multiple places [
4‐
6]. Traditionally, more girls report pain than boys [
2,
6,
7]. Pain can influence daily life in different ways and is linked to poor school performance, problems in social activities, sleep problems, and reduced quality of life [
1,
8]. Moreover, pain problems may contribute to school absenteeism, school impairment, and problems meeting school demands [
9,
10].
The high prevalence is a cause for concern given that pain problems early in life may contribute to pain problems later in life [
11‐
13]. Pain problems in childhood should also be viewed in relation to research showing that backache, limb pain, and other musculoskeletal complaints are frequent causes of sickness certification and disability pensions in adult populations, and are becoming increasingly so among young adults [
14,
15]. These findings indicate that pain can also have serious long-term effects [
11,
16].
Pain is a subjective and individual experience and is often defined as “whatever the experiencing person says it is, existing whenever he says it does” [
17]. This definition stresses that pain is a subjective concept and the importance of accepting the person’s perception and experience of pain.
Pain and physical complaints of children and adolescents may be symptoms of underlying causes and may be related to several psychological, social, and physical factors. The complexity of pain etiology calls for a biopsychosocial understanding and approach [
18]. Health-related quality of life (HRQoL) is a construct that is used to assess children’s subjective perspectives of health and is often used to examine how health problems such as pain can interfere with daily life [
19‐
21]. HRQoL is generally conceptualized as a multidimensional construct that includes the individual’s subjective perspectives on the physical, psychological, social, and functional aspects of health [
22]. The multidimensionality of HRQoL measures may provide researchers and clinicians with information about the impact of a health condition, e.g. pain, on different aspects of quality of life, and may serve as a framework for identifying and develop strategies to promote quality of life, and develop tailored interventions [
20,
22‐
24].
Understanding of pain in children has increased in recent years, and it is recognized that children with pain can experience various problems related to their pain. However, relatively little is known about the associations between pain and HRQoL. There are studies of pain and HRQoL in children [
9,
19‐
25], however, some of the studies have used one global score to measure HRQoL, which make it impossible to identify which dimensions of HRQoL are most affected by pain, and, and some studies focusing on children with chronic pain recruited from pain clinics [
9,
19‐
21,
25]. Clearly, more knowledge is needed on pain and HRQoL in a non-clinical population of children and adolescents.
The aims of this study were to first describe HRQoL and the prevalence of pain in children and adolescents and, second, to analyze the relationships between HRQoL (dependent variable) and pain, sex, and age (independent variables) in a representative sample of children and adolescents aged 8–18 years.
Results
Of the 1675 invited children and adolescents, 258 (15%) did not return the written permission from their parents, 148 (9%) were absent from school on the day of the study, and 31 (2%) did not want to participate. Hence, the final sample comprised 1238 children and adolescents, with an overall response rate of 74%. After excluding children with missing values on the KIDSCREEN scales, the data for 1099 children and adolescents were eligible for analysis.
Tables
1 and
2 presents the characteristics of the sample and descriptive statistics for the ten dimensions of KIDSCREEN-52, sex, age and pain. The study population comprised 1099 children and adolescents: 45.9% boys and 54.1% girls. The largest group of study participants was aged between 12 and 15 years (44.2%), and mean age was 13 years.
Table 1
Characteristics of the sample, by age, sex and nationality, n = 1099
Age |
8–11 yrs | 315 (28.7) |
12–15 yrs | 486 (44.2) |
16–18 yrs | 298 (27.1) |
Sex |
Girls | 595 (54.1) |
Boys | 504 (45.9) |
Table 2
Descriptive statistics for kidscreen, sex, age and pain, n = 1099
Physical well-being | 0 | 100 | 66.73 | 20.32 | −0.38 | −0.47 |
Psychological well-being | 8 | 100 | 77.77 | 17.73 | −1.05 | 0.99 |
Mood | 0 | 100 | 81.60 | 15.00 | −1.47 | 2.70 |
Self-perception | 0 | 100 | 74.34 | 20.76 | −0.85 | 0.09 |
Autonomy | 0 | 100 | 70.45 | 20.48 | −0.61 | −0.07 |
Parents relation | 0 | 100 | 77.81 | 18.79 | −0.98 | 0.68 |
Financial resources | 0 | 100 | 76.11 | 23.93 | −0.95 | 0.24 |
Social support a peers | 0 | 100 | 74.06 | 17.78 | −0.69 | 0.26 |
School environment | 0 | 100 | 66.80 | 20.09 | −0.36 | −0.25 |
Bullying | 0 | 100 | 90.20 | 15.65 | −2.43 | 7.41 |
Sex | 0 | 1 | 0.46 | 0.50 | 0.17 | −1.98 |
Age | 7 | 19 | 13.16 | 2.87 | 0.26 | −0.84 |
Pain | 0.00 | 6.00 | 2.04 | 1.92 | 0.23 | −1.43 |
HRQoL and the prevalence of pain
Table
3 presents the HRQoL and pain prevalence in all 10 domains of the KIDSCREEN-52 according to sex and age. Age was grouped into three categories: 8–11, 12–15, and 16–18 years. Sixty percent of the children reported pain within the previous 3 months, and significantly more girls (64.2%) than boys (53.8%) reported pain (
p < 0.01).
Table 3
Health related quality of life measured with KIDSCREEN-52 and pain by sex and age, n = 1099
Physical well-being | 5 | 69.94 | 66.43 | 54.26 | 64.10 | < 0.001 | 72.62 | 71.05 | 64.85 | 69.84 | 0.002 | < 0.001 | < 0.001 | 66.73 |
Psychological well-being | 6 | 82.89 | 76.70 | 69.66 | 76.54 | < 0.001 | 82.93 | 79.87 | 74.14 | 79.22 | < 0.001 | .013 | < 0.001 | 77.77 |
Mood | 7 | 82.46 | 82.28 | 73.99 | 80.06 | < 0.001 | 83.89 | 83.45 | 82.86 | 83.42 | .814 | < 0.001 | < 0.001 | 81.60 |
Self-perception | 5 | 82.53 | 67.61 | 56.96 | 68.96 | < 0.001 | 86.69 | 80.76 | 74.19 | 80.70 | < 0.001 | < 0.001 | < 0.001 | 74.34 |
Autonomy | 5 | 74.56 | 72.42 | 55.46 | 68.39 | < 0.001 | 75.41 | 74.42 | 67.59 | 72.88 | < 0.001 | < 0.001 | < 0.001 | 70.45 |
Parents relation | 6 | 82.25 | 77.24 | 70.40 | 76.80 | < 0.001 | 83.22 | 78.46 | 75.40 | 79.01 | < 0.001 | .052 | < 0.001 | 77.81 |
Financial resources | 3 | 71.86 | 76.27 | 77.81 | 75.43 | .059 | 71.03 | 79.35 | 79.20 | 76.92 | .002 | .306 | < 0.001 | 76.11 |
Social support and peers | 6 | 77.89 | 75.91 | 72.83 | 75.63 | .030 | 75.55 | 71.63 | 69.57 | 72.21 | .015 | .001 | 0.001 | 74.06 |
School environment | 6 | 79.31 | 67.10 | 57.39 | 67.93 | < 0.001 | 75.37 | 65.63 | 54.60 | 65.48 | < 0.001 | .044 | < 0.001 | 66.80 |
Bullying | 3 | 86.76 | 90.17 | 95.60 | 90.69 | < 0.001 | 85.34 | 90.07 | 93.46 | 89.62 | < 0.001 | .259 | < 0.001 | 90.20 |
Pain n/% | | 72 / 42.4 | 186/71.0 | 124/76.1 | 382/64.2 | < 0.001 | 65/44.8 | 119/53.1 | 87/64.4 | 271/53.8 | 0.004 | < 0.001 | < 0.001 | 653/59.6 |
The KIDSCREEN-52 scores differed between girls and boys. On average, girls reported a significantly lower HRQoL than boys on most dimensions (p < 0.01) except for relationship with parents, financial resources, and bullying. For girls, the lowest scores were reported for physical well-being, self-perception, school, and autonomy. For boys, the lowest scores were for the school environment and physical well-being. HRQoL decreased significantly with age for both boys and girls, except for the subscales of relationship with parents, financial resources, bullying, and the school environment.
Relationship between HRQoL, age, sex, and pain
Table
4 shows the significant results (
p < 0.05) for the total R
2 values and the unique contributions of each of the independent variables. In model 1, R
2 varied between 0.013 and 0.217, meaning that sex and age accounted for 1–22% of the variance in the KIDSCREEN-52 subscales. Age made the largest contribution in all subscales. However, sex predicted 8% of the variance in the self-perception subscale, which had the largest contribution to the effect of sex in this model. Adding the interaction between sex and age increased the predicted variance significantly in the subscales physical well-being, mood, self-perception, and autonomy. This indicates that the effect of age is different for boys and girls, girls are more impaired than boys.
Table 4
Unique and total predicted variance of HRQOL measured with KIDSCREEN-52 due to sex. Age. pain and interaction between sex and age, n = 1099
Physical well-being | 0.141 | −0.239 | −0.199 | 0.076 | 0.019 | 0.056 | 0.082 | 0.006 | 0.092 | 0.016 |
Psychological well-being | 0.075 | −0.259 | −0.257 | 0.072 | 0.005 | 0.067 | 0.075 | | 0.107 | 0.035 |
Mood | 0.112 | −0.152 | −0.266 | 0.035 | 0.012 | 0.023 | 0.046 | 0.011 | 0.085 | 0.050 |
Self-perception | 0.282 | −0.375 | −0.301 | 0.217 | 0.076 | 0.137 | 0.235 | 0.018 | 0.248 | 0.031 |
Autonomy | 0.109 | −0.273 | −0.207 | 0.085 | 0.011 | 0.074 | 0.098 | 0.012 | 0.102 | 0.016 |
Parents relation | | −0.220 | −0.244 | 0.052 | | 0.048 | 0.053 | | 0.086 | 0.035 |
Financial resources | | 0.109 | −0.090 | 0.013 | | 0.012 | 0.013 | | 0.028 | 0.015 |
Social support and peers | −0.096 | −0.128 | −0.109 | 0.026 | 0.010 | 0.017 | 0.026 | | 0.034 | 0.008 |
School environment | .0.061 | −0.409 | −0.272 | 0.171 | 0.004 | 0.168 | 0.172 | | 0.203 | 0.031 |
Bullying | | 0.193 | −0.097 | 0.038 | | 0.037 | 0.038 | | 0.064 | 0.025 |
Adding pain resulted in small changes in the predicted variance, however pain contributed significantly to explain variations in the subscales. As shown in Table
4, pain correlated negatively and moderately with the HRQoL subscales. Impaired HRQoL was prevalent in children with pain for all 10 dimensions of the KIDSCREEN-52 questionnaire. The children and adolescents with pain had a substantially lower HRQoL than did their peers who reported no pain. The subscales self-perception, psychological well-being, mood, autonomy and school environment were most affected.
Discussion
The current study describes HRQoL and the prevalence of pain, and analyzes the associations between HRQoL, pain, sex, and age in a nonclinical population of children and adolescents. The results confirm the findings of earlier studies and show that pain is a common problem in young people. More than 60% of the children in this study reported pain in the previous 3 months. More girls than boys reported pain, and the prevalence of pain was highest in girls in the age group 16–18 years.
These results are consistent with those reported by other studies [
4,
5,
7,
9,
20,
31,
32]. A Danish study of adolescents aged 12–19 years found a pain prevalence of 61%. The Norwegian HUNT study reported a pain prevalence of 44%, (pain once a week the last three months) among adolescents in a nonclinical population aged 13–18 years [
7]. A systematic review of 32 studies on chronic pain in children found a high prevalence of chronic and recurrent pain in nonclinical populations and an increasing prevalence with age. The finding from this review indicated that most types of pain are more prevalent in girls than in boys. In the study, prevalence was described in relation to type of pain, and it is therefore difficult to make general conclusions regarding prevalence, however, the results indicated that pain is overwhelmingly prevalent in children, and should be regarded as a major health concern [
4].
The prevalence varies between studies because of the use of different methods, age groups, and use of questionnaires, which makes it difficult to compare the results. However, most studies have shown a trend toward a high prevalence of pain in children and adolescents, especially in adolescent girls, and that pain is an increasing problem [
4,
31‐
33].
The high prevalence of pain is worrying, and one of the aims of our study wasto examine the association with HRQoL and how children and adolescents with pain perceive their quality of life.
The results from the HRQoL analyses are consistent with previous findings showing that HRQoL varies between sexes on most subscales; that is, girls have poorer HRQoL than boys. However, the greatest variation in HRQoL is seen between different age groups, and age contributes significantly to explaining the variations in all of the HRQoL subscales. Overall, increasing age is associated with decreasing HRQoL. Earlier studies of HRQoL in children and adolescents have found sex and age differences [
34,
35,
36]. Physical and mental well-being, in particular, seem to deteriorate with age and more so for girls than for boys. These changes may reflect the developmental challenges that adolescents experience, including physical, psychological, vocational, and social changes [
36,
37].
The results from the bivariate analysis show that having pain was associated with a lower HRQoL in all subscales of the KIDSCREEN-52. Moreover, the interaction between sex and age increase the explained variance in the scales physical, mood, self-perception, and autonomy. This result is significant but rather small, however it indicates that the effect of age is different for boys and girls.
Even though pain was significantly associated with lower HRQoL in all KIDSCREEN-52 subscales, our analysis shows that adding pain into the model resulted in small changes in the explained variance; that is, pain was not found to be a strong explanatory factor for variations in HRQoL. This is in line with a study of American children (mean age 14 years) with chronic pain, which showed that pain did not account for the significant variance in HRQoL after controlling for demographics [
19]. However, in our study, pain contributed significantly to explain the variations in the domains of psychological well-being, mood and emotions, self-perception, relationship with parents, and school environment. Our results indicate that children with pain are generally less happy, have a less positive perception of themselves, are less satisfied with their relationship with parents, and are less positive about going to school.
It is notable that children with pain had a low score on the school dimension in the KIDSCREEN-52, which includes satisfaction with one’s own ability to perform at school and general feelings about school. Similar results were reported in a Canadian study, in which children with pain were more likely to report fair or poor self-rated health, psychological health complaints, and greater unhappiness with school experiences [
32,
33]. School and friends are significant arenas for social development, especially during adolescence. Children with pain may be more absent from school and miss theoretical and social experiences, which are fundamental to healthy development. A study of adolescents with chronic diseases found an increased risk of sickness and disabilities later in young adulthood [
37]. In the current study, the self-perception and mood scores were low in children with pain and were lowest for older girls. Earlier studies indicate that girls are more affected by health problems and have more worries than do boys [
38]. The score on the relationship with parents was low, and this subscale reflects the extent to which a child feels supported by his/her family [
28]. Parents play an important role in helping and supporting how their children experience pain so that it does not lead to chronic pain. Pain is a subjective experience, and parents may differ in their sensitivity and ability to perceive and support their children’s complaints [
39].
The results of our study are consistent with previous research demonstrating the importance of psychosocial factors to HRQoL among children with pain [
21]. A few other studies have reported an association between pain and HRQoL in a nonclinical population. In a Swedish study of children aged 9 and 12 years, young schoolchildren with recurrent pain had a considerably impaired HRQoL. Pain was measured using questions from the international World Health Organization Health Behaviour in School-aged Children study. HRQoL impairment was twice as common in children with recurrent pain as in children without pain [
24]. A Danish study among 4000 adolescents aged 12–19 years, found an association between pain problems and lower HRQoL; however, HRQoL was measured with the EQ. 5D questionnaire, and no single dimensions could be identified [
25].
Our findings emphasize the vulnerability of adolescents, especially adolescent girls. Adolescence is a period when many changes occur over a relatively short time, and adolescents are faced with many physical, psychological, and social changes. Pain problems can negatively influence a young person’s life during this vulnerable period in life, and should be regarded as a significant health concern [
9,
40,
41].
Strengths and limitations
There are several strengths and limitations of this study. The relatively high response rate strengthens our ability to generalize from the results. The large sample size ensures that the results are representative of children in the eastern part of Norway. The Norwegian school system is fairly homogeneous, and the findings would probably be similar for this age group (8–18 years) in other Norwegian regions.
One limitation is that this was a cross-sectional study and, therefore, it is not possible to make substantial causal inferences. Measures of subjective symptoms, such as pain and the causes of pain, in children and adolescents may be influenced by other factors. Moreover, for younger children, it may be difficult to read and complete a questionnaire that requires them to remember information from the preceding 3 months (Lübeck Pain-Screening Questionnaire). A long recall period may weaken the content validity. However, the KIDSCREEN-52 has a recall period of 1 week, which is more appropriate [
22,
28]. The different recall periods in the two questionnaires used may have been difficult, especially for the younger children. There was no additional sampling of children and adolescents who were absent on the day of the study. Children with health problems are more likely to be absent from school, and some of them might have been absent because of pain. However, the overall response rate of 74% is considered satisfactory [
42].
Conclusions
The findings from this study indicate that pain problems are highly prevalent in children and adolescents, and, and more prevalent in girls than in boys. Further, there is evidence that pain experienced by children and adolescents in a school sample affects all dimensions of HRQoL negatively. In KIDSCREEN 52, the subscales self-perception, psychological well-being, mood, relationship with parents, and school environment were most affected.
Early intervention and prevention of pain problems should be of great concern, especially for those involved in school health care. It is important to provide young people with strategies to manage their own health and to prevent negative consequences of pain problems. Further studies are required, especially longitudinal studies, to investigate the relationship between pain in childhood and later HRQoL.