title: Evaluation of two methods to measure hemoglobin concentration among women with genetic hemoglobin disorders in Cambodia: a method-comparison study.
abstract: BACKGROUND
  Genetic hemoglobin (Hb) E variants are common in Cambodia and result in an altered and unstable Hb molecule. We evaluated two methods to measure Hb concentration among individuals with and without Hb variants using a hemoglobinometer (HemoCue) and a hematology analyzer (Sysmex XT-1800i).
  
  
  METHODS
  We determined the bias and concordance between the methods among 420 Cambodian women (18-45 y).
  
  
  RESULTS
  Bias and concordance appeared similar between methods among women with no Hb disorders (n=195, bias=2.5, ρc=0.68), women with Hb E variants (n=133, bias=2.5, ρc=0.78), and women with other Hb variants (n=92, bias=2.7, ρc=0.73). The overall bias was 2.6g/l, resulting in a difference in anemia prevalence of 11.5% (41% using HemoCue and 29.5% using Sysmex, p<0.001). Based on visual interpretation of the concordance plots, the HemoCue device appears to underestimate Hb concentrations at lower Hb concentrations and to overestimate Hb concentrations at higher Hb concentrations (in comparison to the Sysmex analyzer).
  
  
  CONCLUSIONS
  Bias and concordance were similar across groups, suggesting the two methods of Hb measurement were comparable. We caution field staff, researchers and policy makers in the interpretation of data and the impact that bias between methods can have on anemia prevalence rates.
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada. Electronic address: c_karakochuk@hotmail.com.
authors.forename: Crystal D
authors.initials: CD
authors.lastname: Karakochuk
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Amynah
authors.initials: A
authors.lastname: Janmohamed
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Kyly C
authors.initials: KC
authors.lastname: Whitfield
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Susan I
authors.initials: SI
authors.lastname: Barr
authors.affiliation: Children's & Women's Health Centre of British Columbia, Division of Hematopathology, 4480 Oak Street, Vancouver, BC V6H 3V4, Canada.
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Vercauteren
authors.affiliation: Helen Keller International, Cambodia Country Office, P.O. Box 168, Phnom Penh, Cambodia.
authors.forename: Hou
authors.initials: H
authors.lastname: Kroeun
authors.affiliation: Helen Keller International, Cambodia Country Office, P.O. Box 168, Phnom Penh, Cambodia.
authors.forename: Aminuzzaman
authors.initials: A
authors.lastname: Talukder
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Judy
authors.initials: J
authors.lastname: McLean
authors.affiliation: Food, Nutrition and Health, University of British Columbia, 2205 East Mall, Vancouver, BC V6T 1Z4, Canada.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Green
mesh_terms: D000293:Adolescent; D000328:Adult; D002160:Cambodia; D005260:Female; D006403:Hematologic Tests; D006446:Hemoglobin E / Q000032:analysis* / Q000235:genetics*; D006453:Hemoglobinopathies / Q000097:blood* / Q000235:genetics*; D006801:Humans; D008875:Middle Aged; D055815:Young Adult
chemical_list: D006446:Hemoglobin E
keywords: Anemia; Bias; Cambodia; HemoCue; Hemoglobin; Method-comparison