Low health-related quality of life in school-aged children in Tonga, a lower-middle income country in the South Pacific

Figures & data

Table 1 Basic characteristics of the participants in Tonga

	N	%
All children	2,164	100.0
Sex
Boys	989	45.7
Girls	1,174	54.3
Age (years)
11	110	5.1
12	231	10.7
13	372	17.2
14	353	16.3
15	362	16.7
16	358	16.5
17	241	11.1
18	137	6.3
Age group (years)
<15	1,066	49.3
≥15	1,098	50.7
Ethnicity
Indigenous	2,123	98.1
Others	41	1.9
Residential location
Tongatapu	1,077	49.8
Vava'u	1,087	50.2
Family structure during the school week
Living with
2 parents	1,469	67.9
1 parent	309	14.3
Other adult relatives	224	10.4
At boarding school	103	4.8
None of the above	54	2.5
Unknown	4	0.2
Household size
1–5 persons	558	25.8
6–10 persons	1,221	56.4
11–16 persons	279	12.9
Unknown	106	4.9

Table 2 Self-rated health-related quality of life (HRQoL) and subdomains of HRQoL by socio-demography in 11–18 year old school children in Tonga

						Age group				Sex				Residential location
	All					11–14 years	15–18 years			Girls	Boys			Tongatapu	Vava'u
		Percentiles
	N	25	50	75	Mean (SD)	Mean (SD)	Mean (SD)	p	Cohen's d	Mean (SD)	Mean (SD)	p	Cohen's d	Mean (SD)	Mean (SD)	p	Cohen's d
HRQoL	2,110	58.70	69.57	80.43	69.35 (15.87)	67.59 (16.41)	71.04 (15.15)	**	0.22	69.20 (15.01)	69.51 (16.85)		0.02	69.64 (16.42)	69.07 (15.34)		0.04
Physical functioning and wellbeing	2,164	56.25	71.88	87.50	71.34 (19.60)	68.60 (20.11)	73.98 (18.74)	**	0.28	70.90 (18.33)	71.84 (21.01)		0.05	71.23 (19.85)	71.44 (19.37)		0.01
Psychosocial functioning and wellbeing	2,110	56.67	68.33	80.00	68.20 (16.67)	67.04 (17.17)	69.32 (16.09)	**	0.14	68.22 (16.06)	68.17 (17.38)		0.00	68.62 (17.26)	67.80 (16.08)		0.05
Emotional functioning and wellbeing	2,156	50.00	65.00	80.00	64.78 (21.03)	64.00 (20.98)	65.53 (21.07)		0.07	62.42 (20.64)	67.57 (21.17)	**	0.25	65.75 (21.48)	63.82 (20.54)	*	0.09
Social functioning and wellbeing	2,120	60.00	75.00	90.00	72.97 (20.14)	70.38 (20.99)	75.49 (18.96)	**	0.26	73.67 (19.17)	72.15 (21.24)		0.08	73.00 (20.39)	72.94 (19.91)		0.00
School functioning and wellbeing	2,162	50.00	65.00	80.00	66.70 (19.40)	66.59 (19.86)	66.77 (18.94)		0.01	68.44 (18.79)	64.60 (19.89)	**	0.20	66.76 (19.46)	66.64 (19.36)		0.01

SD: standard deviation. Cohen's d specifies magnitude of difference between groups; values of 0.2 nominated as small; 0.5 as medium and 0.8 as large.

*p<0.05, *p<0.001.

Table 3 Basic characteristics of the community-based comparison group

Country	Sample	N	Age (years)	Income classification^a
Australia (35)	Regional school-based	2,890	11–18	High
Austria (23)	Regional school-based	1,185	8–12	High
Japan (13)	Regional school-based	922	6–18	High
Finland (24)	Regional school-based	1,033	9–10	High
Greece (25)	National school-based	645	8–12	High
Korea (33)	Regional school-based	1,425	8–18	High
Norway (26)	Regional school-based	425	13–15	High
Netherlands (14)	Regional school-based	185	13–18	High
Singapore (32)	School-based	1,249	11–18	High
Spain (27)	Regional school-based	511	9–17	High
United Kingdom (28)	Regional school-based	1,034	8–18	High
USA (21)	Regional household (low-income sample)	5,972	5–16	High
Brazil (22)	Regional school-based (low-income sample)	180	5–18	Upper middle
China (Taiwan) (34)	Regional school-based	519	M 10.5 (SD 1.1)	Upper middle
Iran (15)	Regional school-based	1,188	M 15.7 (SD 1.2)	Upper middle
Jordan (30)	National school-based	150	8–13	Upper middle
Thailand (31)	Regional school-based	2,086	8–15	Upper middle
Serbia (29)	School-based	238	8–18	Upper middle
Fiji (6)	Regional school-based	8,947	12–18	Lower middle

Numbers in brackets after the country refers to the reference list.

^aWorld Bank classification.

Fig. 1 Comparison of self-rated, health-related quality of Life (HRQoL) and subdomains of HRQoL between community based samples of school-aged children in Tonga (grey stippled line, open circle) and in 12 high-income countries (black lines), six upper-middle income countries (grey lines), and one lower-middle income country (grey stippled line, closed circle) (adapted from Refs. (6, 13–15, 21–35)). HRQoL is assessed by the PedsQL 4.0 in all samples.

Table 4 Comparison of health-related quality of life (HRQoL) and subdomains of HRQoL, in 2,123^a Tongan secondary school children in Tonga and 830 Tongans in New Zealand (NZ), by age groups and sex

		HRQoL	Physical	Emotional	Social	School
All
Tongans in Tonga (1)	Mean (SD)	69.38 (15.78)	71.36 (19.54)	64.79 (20.95)	73.03 (20.09)	66.74 (19.38)
Tongans in NZ (2)	Mean (SD)	78.74 (13.76)	82.29 (15.97)	76.61 (19.81)	82.21 (17.86)	71.63 (18.68)
1 vs. 2	p	0.000	0.000	0.000	0.000	0.000
	1<2 (%)	11.9	13.3	15.4	11.2	6.8
	Cohen's d	0.63	0.61	0.58	0.48	0.26
Age 11–14 years
Tongans in Tonga (1)	Mean (SD)	67.71 (16.32)	68.73 (20.02)	64.07 (20.94)	70.55 (20.95)	66.66 (19.84)
Tongans in NZ (2)	Mean (SD)	79.01 (13.75)	82.84 (14.84)	77.11 (19.68)	80.46 (18.78)	73.34 (18.26)
1 vs. 2	p	0.000	0.000	0.000	0.000	0.000
	1<2 (%)	14.3	17.0	16.9	12.3	9.1
	Cohen's d	0.75	0.80	0.64	0.50	0.35
Age 15–18 years
Tongans in Tonga (1)	Mean (SD)	71.01 (15.08)	73.93 (18.71)	65.49 (20.96)	75.45 (18.92)	66.83 (18.93)
Tongans in NZ (2)	Mean (SD)	78.55 (13.77)	81.89 (16.72)	76.26 (19.91)	83.45 (17.09)	70.41 (18.90)
1 vs. 2	p	0.000	0.000	0.000	0.000	0.000
	1<2 (%)	9.6	9.7	14.1	9.6	5.1
	Cohen's d	0.52	0.45	0.53	0.44	0.19
Girls
Tongans in Tonga (1)	Mean (SD)	69.34 (14.82)	71.03 (18.17)	62.46 (20.51)	73.86 (19.03)	68.60 (18.75)
Tongans in NZ (2)	Mean (SD)	78.01 (13.90)	79.97 (16.42)	75.89 (19.74)	82.23 (18.00)	72.59 (18.46)
1 vs. 2	p	0.000	0.000	0.000	0.000	0.000
	1<2 (%)	11.1	11.2	17.7	10.2	5.5
	Cohen's d	0.60	0.52	0.67	0.45	0.21
Boys
Tongans in Tonga (1)	Mean (SD)	69.43 (16.86)	71.73 (21.03)	67.50 (21.16)	72.08 (21.24)	64.55 (19.86)
Tongans in NZ (2)	Mean (SD)	79.49 (13.58)	84.67 (15.14)	77.35 (19.87)	82.19 (17.75)	70.64 (18.88)
1 vs. 2	p	0.000	0.000	0.000	0.000	0.000
	1<2 (%)	12.7	15.3	12.7	12.3	8.6
	Cohen's d	0.66	0.71	0.48	0.52	0.31

SD: standard deviation. Cohen's d specifies magnitude of difference between groups; values of 0.2 nominated as small; 0.5 as medium and 0.8 as large.

^aChildren of non-Tongan ethnicity excluded.

Keating CL, Moodie ML, Swinburn BA. The health-related quality of life of overweight and obese adolescents-a study measuring body mass index and adolescent-reported perceptions. Int J Pediatr Obes. 2011; 6: 434–41.

 PubMed Web of Science ®Google Scholar

Felder-Puig R, Baumgartner M, Topf R, Gadner H, Formann AK. Health-related quality of life in Austrian elementary school children. Med Care. 2008; 46: 432–9.

 PubMed Web of Science ®Google Scholar

Kobayashi K, Kamibeppu K. Measuring quality of life in Japanese children: development of the Japanese version of PedsQL. Pediatr Int. 2010; 52: 80–8.

 PubMed Web of Science ®Google Scholar

Laaksonen C, Aromaa M, Heinonen OJ, Suominen S, Salantera S. Paediatric health-related quality of life instrument for primary school children: cross-cultural validation. J Adv Nurs. 2007; 59: 542–50.

 PubMed Web of Science ®Google Scholar

Gkoltsiou K, Dimitrakaki C, Tzavara C, Papaevangelou V, Varni JW, Tountas Y. Measuring health-related quality of life in Greek children: psychometric properties of the Greek version of the Pediatric Quality of Life Inventory(TM) 4.0 Generic Core Scales. Qual Life Res. 2008; 17: 299–305.

 PubMed Web of Science ®Google Scholar

Kook SH, Varni JW. Validation of the Korean version of the pediatric quality of life inventory™ 4.0 (PedsQL™) generic core scales in school children and adolescents using the rasch model. Health Qual Life Outcome. 2008; 6: 41.

 PubMed Web of Science ®Google Scholar

Reinfjell T, Diseth TH, Veenstra M, Vikan A. Measuring health-related quality of life in young adolescents: reliability and validity in the Norwegian version of the Pediatric Quality of Life Inventory 4.0 (PedsQL) generic core scales. Health Qual Life Outcome. 2006; 4: 61.

 PubMed Web of Science ®Google Scholar

Engelen V, Haentjens MM, Detmar SB, Koopman HM, Grootenhuis MA. Health related quality of life of Dutch children: psychometric properties of the PedsQL in the Netherlands. BMC Pediatr. 2009; 9: 68.

 PubMed Web of Science ®Google Scholar

Ostbye T, Malhotra R, Wong HB, Tan SB, Saw SM. The effect of body mass on health-related quality of life among Singaporean adolescents: results from the SCORM study. Qual Life Res. 2010; 19: 167–76.

 PubMed Web of Science ®Google Scholar

Huguet A, Miro J. Development and psychometric evaluation of a Catalan self- and interviewer-administered version of the Pediatric Quality of Life Inventory version 4.0. J Pediatr Psychol. 2008; 33: 63–79.

 PubMed Web of Science ®Google Scholar

Upton P, Eiser C, Cheung I, Hutchings HA, Jenney M, Maddocks A, etal. Measurement properties of the UK-English version of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™) generic core scales. Health Qual Life Outcome. 2005; 3: 22.

 PubMedGoogle Scholar

Varni JW, Burwinkle TM, Seid M, Skarr D. The PedsQL 4.0 as a pediatric population health measure: feasibility, reliability, and validity. Ambul Pediatr. 2003; 3: 329–41.

 PubMedGoogle Scholar

Klatchoian DA, Len CA, Terreri MT, Hilario MO. Quality of life among children from Sao Paulo, Brazil: the impact of demographic, family and socioeconomic variables. Cad Saude Publica. 2010; 26: 631–6.

 PubMed Web of Science ®Google Scholar

Lin C-Y, Luh W-M, Cheng C-P, Yang A-L, Su C-T, Ma H-I. Measurement equivalence across child self-reports and parent-proxy reports in the Chinese version of the Pediatric Quality of Life Inventory version 4.0. Child Psychiatry Hum Dev. 2013; 44: 583–90.

 PubMed Web of Science ®Google Scholar

Amiri P, Ardekani EM, Jalali-Farahani S, Hosseinpanah F, Varni JW, Ghofranipour F, etal. Reliability and validity of the Iranian version of the Pediatric Quality of Life Inventory 4.0 Generic Core Scales in adolescents. Qual Life Res. 2010; 19: 1501–8.

 PubMed Web of Science ®Google Scholar

Arabiat D, Elliott B, Draper P, Jabery MAI. Cross-cultural validation of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™) generic core scale into Arabic language. Scand J Caring Sci. 2011; 25: 828–33.

 PubMed Web of Science ®Google Scholar

Sritipsukho P, Wisai M, Thavorncharoensap M. Reliability and validity of the Thai version of the Pediatric Quality of Life Inventory 4.0. Qual Life Res. 2013; 22: 551–7.

 PubMed Web of Science ®Google Scholar

Stevanović D, Lakić A, Damnjanović M. Some psychometric properties of the Pediatric Quality of Life Inventory™ Version 4.0 Generic Core Scales (PedsQL™) in the general Serbian population. Qual Life Res. 2011; 20: 945–9.

 PubMed Web of Science ®Google Scholar

Petersen S, Mavoa H, Swinburn B, Waga G, Gounder R, Moodie M. Health-related quality of life is low in secondary school children in Fiji. Int J Pediatr. 2012; 2012: 10.

 Google Scholar