title: Enhanced liver fibrosis (ELF) score: Analytical performance and distribution range in a large cohort of blood donors.
abstract: BACKGROUND
  The Enhanced Liver Fibrosis (ELF) is a serological score that includes hyaluronic acid (HA), tissue inhibitor of matrix metalloproteinases-1(TIMP-1), and aminoterminal propeptide of type III procollagen (PIIINP) and shows good performance for detecting liver fibrosis. There are few studies evaluating ELF's intra and inter-assay variation and stability of the samples. The influence of host variables, such as age, gender and body mass index (BMI) is also not well known. We determined ELF's analytical performance and possible influences of gender, age and BMI.
  
  
  METHODS
  The study included 958 healthy blood donors evaluated for age, gender, and BMI.
  
  
  RESULTS
  Mean ELF scores were significantly different between female (8.53±0.75) and male groups (8.76±0.76) and also according to age strata (p<0.001). For both genders, ELF significantly varied in individuals with BMI under 25 (p<0.001). Analytes remained stable after freezing/thawing cycles and intra- and inter-assay coefficients of variation were low.
  
  
  CONCLUSIONS
  ELF has appropriate precision and is quite robust, due to the high stability of the analytes in fresh and frozen samples. ELF's results are influenced by gender, age and BMI which should be taken into account when analyzing its results.
authors: Research and Development Division, Fleury Group, São Paulo, Brazil.
authors: Alessandra
authors: A
authors: Dellavance
authors: University of the State of Rio de Janeiro, Gastroenterology and Hepatology Department, Rio de Janeiro, Brazil; Bonsucesso Federal Hospital, Gastroenterology and Hepatology Department, Rio de Janeiro, Brazil. Electronic address: ffernandes.flavia@gmail.com.
authors: Flávia
authors: F
authors: Fernandes
authors: Federal University of São Paulo, Rheumatology Division, UNIFESP, São Paulo, Brazil.
authors: Natália
authors: N
authors: Shimabokuro
authors: Benevolent Association of Blood Collection, Colsan, São Paulo, Brazil.
authors: Flavia
authors: F
authors: Latini
authors: Research and Development Division, Fleury Group, São Paulo, Brazil.
authors: Danielle
authors: D
authors: Baldo
authors: Benevolent Association of Blood Collection, Colsan, São Paulo, Brazil.
authors: José Augusto
authors: JA
authors: Barreto
authors: Federal University of São Paulo, Statistics Department, UNIFESP, São Paulo, Brazil.
authors: Valdecir
authors: V
authors: Marvulle
authors: Federal University of São Paulo, Rheumatology Department, São Paulo, Brazil.
authors: Luis Eduardo
authors: LE
authors: Andrade
authors: Federal University of São Paulo, Gastroenterology Department, São Paulo, Brazil; D'Or Institute for Research and Education, Rio de Janeiro, Brazil.
authors: Maria Lucia
authors: ML
authors: Ferraz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001782:Blood Donors; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000097:blood*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: Coefficient of variation; Elf; Hyaluronic acid; Liver fibrosis; Metalloproteinases