Meta-Analysis of the Association between Body Mass Index and Health-Related Quality of Life among Children and Adolescents, Assessed Using the Pediatric Quality of Life Inventory Index Zia Ul-Haq, MBBS, MPH, Daniel F. Mackay, PhD, Elisabeth Fenwick, PhD, and Jill P. Pell, MBChB, MD Objective To explore the relationships between body mass index and overall, physical, and psychosocial health- related quality of life (HRQoL) in children and adolescents. Study design A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Medline, Embase, PsycINFO, and the Web of Knowledge were searched for relevant articles. Inclusion was restricted to participants under 20 years of age, assessed using the Pediatric Quality of Life Inventory. Random-effects meta-analysis, meta-regression, and cumulative meta-analysis were conducted. Heterogeneity was assessed using the I 2 statistic, and potential publication and small study bias were evaluated using funnel plots and the Egger test. Results Eleven eligible studies provided 35 estimates of effect size, derived from a total of 13 210 study partici- pants. Based on self-reports, children and adolescents with above-normal body mass index had significantly lower total, physical, and psychosocial HRQoL, with a clear dose relationship across all categories. In obese children and adolescents, the overall score was reduced by 10.6 points (95% CI, 14.0-7.2; P < .001). Parents reported the same pattern but a larger effect size. The total parental score for obese children and adolescents was reduced by 18.9 points (95% CI, 26.6-11.1; P < .001). No significant publication or small study bias was observed. Conclusion Parents overestimate the impact of obesity on the HRQoL of their children. Nonetheless, obese children and adolescents have significantly reduced overall, physical, and psychosocial HRQoL. (J Pediatr 2013;162:280-6). R ecent estimates suggest that worldwide, approximately 43 million children under age 5 years are overweight, including 35 million in developing countries and 8 million in developed countries. 1 The prevalence of overweight and obesity in children and adolescents is increasing. 2-4 Obesity in childhood predisposes to obesity in adulthood, which in turn in- creases the risk of poor health and reduced life expectancy. 5,6 The relationship between adult obesity and health-related quality of life (HRQoL) is complex. Physical HRQoL demonstrates a dose relationship, decreasing steadily with increasing body mass index (BMI) from the normal range to obese. 7,8 In contrast, mental HRQoL is significantly reduced in obese adults, but not in overweight adults. 7 The relationship between childhood obesity and HRQoL is unclear. Previous studies using a mixture of self and parental reporting have yielded conflicting results. A systematic review published in 2009 9 suggested that HRQoL improves with weight loss, and pooled regression analyses showed that pediatric HRQoL can be predicted from parent proxy reports, even though parents tend to perceive worse HRQoL than children. 9 No meta-analysis has been reported to date. We undertook an updated systematic review and meta-analysis of published studies to examine the associations between childhood/adolescent BMI and overall, physical, and psychosocial HRQoL, and to determine whether parental perceptions of impact differ from the children’s self-reports. Methods We performed a systematic review of published articles in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines (http://www.prisma-statement.org/). The relevant search terms ("obes * " or "BMI" or "body mass index" or "overweight") and ("HRQoL" or "quality of life" or "QoL") were applied to 4 electronic databases: Embase, Medline, ISI Web of Knowledge, and PsycINFO. The last search was undertaken on August 1, 2011. The electronic search was limited to studies conducted on humans and written in, or translated into, English. The identified articles were then reviewed manually, and their reference lists checked for any additional relevant studies. Articles reporting studies conducted in children and or adolescents, defined as From the Institute for Health and Wellbeing, University of Glasgow, Glasgow, United Kingdom Z.U.-H. is sponsored by the Higher Education Commission, Pakistan (Development of Khyber Medical University, Peshawar). The authors declare no conflicts of interest. 0022-3476/$ - see front matter. Copyright ª 2013 Mosby Inc. All rights reserved. http://dx.doi.org/10.1016/j.jpeds.2012.07.049 BMI Body mass index HRQoL Health-related quality of life PedsQL Pediatric Quality of Life Inventory PRISMA Preferred Reporting Items for Systematic Review and Meta-Analysis 280