title: Socioeconomic disparities in survival from childhood leukemia in the United States and globally: a meta-analysis.
abstract: BACKGROUND
  Despite advancements in the treatment of childhood leukemia, socioeconomic status (SES) may potentially affect disease prognosis. This study aims to evaluate whether SES is associated with survival from childhood leukemia.
  
  
  METHODS
  The US National Cancer Institute Surveillance, Epidemiology and End Results Program (SEER) 1973-2010 data were analyzed; thereafter, results were meta-analyzed along with those from survival (cohort) studies examining the association between SES indices and survival from childhood leukemia (end-of-search date: 31 March 2014). Random-effects models were used to calculate pooled effect estimates (relative risks, RRs); meta-regression was also used.
  
  
  RESULTS
  We included 29 studies yielding 28 804 acute lymphoblastic leukemia (ALL), 3208 acute myeloblastic leukemia (AML) and 27 650 'any' leukemia (denoting joint reporting of all subtypes) cases. According to individual-level composite SES indices, children from low SES suffered from nearly twofold higher death rates from ALL (pooled RR: 1.83, 95% confidence interval 1.00-3.34, based on four study arms); likewise, death RRs derived from an array of lower area-level SES indices ranged between 1.17 and 1.33 (based on 11 study arms). Importantly, the survival gap between higher and lower SES seemed wider in the United States, with considerably (by 20%-82%) increased RRs for death from ALL in lower SES. Regarding AML, poorer survival was evident only when area-level SES indices were used. Lastly, remoteness indices were not associated with survival from childhood leukemia.
  
  
  CONCLUSIONS
  Children with lower SES suffering childhood leukemia do not seem to equally enjoy the impressive recent survival gains. Special health policy strategies and increased awareness of health providers might minimize the effects of socioeconomic disparities.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens epetrid@med.uoa.gr.
authors.forename: E T
authors.initials: ET
authors.lastname: Petridou
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens.
authors.forename: T N
authors.initials: TN
authors.lastname: Sergentanis
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens.
authors.forename: C
authors.initials: C
authors.lastname: Perlepe
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens.
authors.forename: P
authors.initials: P
authors.lastname: Papathoma
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens.
authors.forename: G
authors.initials: G
authors.lastname: Tsilimidos
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens.
authors.forename: E
authors.initials: E
authors.lastname: Kontogeorgi
authors.affiliation: Hematology-Oncology Unit, Department of Pediatric Oncology, Hippokration Hospital, Thessaloniki.
authors.forename: M
authors.initials: M
authors.lastname: Kourti
authors.affiliation: Department of Pediatric Hematology-Oncology, 'Pan. & Agl. Kyriakou' Children's Hospital, Athens.
authors.forename: M
authors.initials: M
authors.lastname: Baka
authors.affiliation: First Department of Pediatrics, Athens University Medical School.
authors.forename: M
authors.initials: M
authors.lastname: Moschovi
authors.affiliation: Department of Pediatric Hematology-Oncology, 'Aghia Sophia' General Children's Hospital, Athens.
authors.forename: S
authors.initials: S
authors.lastname: Polychronopoulou
authors.affiliation: Hematology-Oncology Unit, Department of Pediatric Oncology, Hippokration Hospital, Thessaloniki.
authors.forename: V
authors.initials: V
authors.lastname: Sidi
authors.affiliation: 2nd Department of Pediatrics, Aristotelion University of Thessaloniki, AHEPA General Hospital, Thessaloniki.
authors.forename: E
authors.initials: E
authors.lastname: Hatzipantelis
authors.affiliation: Department of Pediatric Hematology-Oncology, University Hospital of Heraklion, Heraklion, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Stiakaki
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: A N
authors.initials: AN
authors.lastname: Iliadou
authors.affiliation: Department of Epidemiology, Istituto di Ricerche Farmacologiche 'Mario Negri', Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: La Vecchia
authors.affiliation: Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Skalkidou
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden Department of Epidemiology, Harvard School of Public Health, Boston, USA.
authors.forename: H O
authors.initials: HO
authors.lastname: Adami
mesh_terms: D002648:Child; D015331:Cohort Studies; D014943:Global Health / Q000191:economics*; D054625:Healthcare Disparities / Q000191:economics*; D006801:Humans; D007938:Leukemia / Q000175:diagnosis / Q000191:economics* / Q000401:mortality*; D012923:Social Class; D012959:Socioeconomic Factors; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology
keywords: childhood leukemia; health policy; meta-analysis; socioeconomic status; survival