title: Reporting results after bariatric surgery: reproducibility of predicted body mass index.
abstract: BACKGROUND
  There is a controversy about the best way to report results after bariatric surgery. Several indices have been proposed over the years such as percentage of total weight loss (%TWL), percentage of excess weight loss (%EWL), and percentage of excess body mass index loss (%EBMIL). More recently, it has been suggested to individualize the body mass index (BMI) goal to be achieved by the patients (predicted BMI-PBMI). The objective was to assess the reproducibility of this PBMI in our service.
  
  
  METHODS
  In this retrospective study, we assessed the %TWL, %EWL, %EBMIL (with expected BMI of 25 kg/m2), and %EBMIL (with PBMI) over 4 years of observation in two groups of patients: BMI <50 kg/m2 and BMI ≥50 kg/m2.
  
  
  RESULTS
  The medical records of 403 patients were studied. From 18 to 42 months after surgery, %TWL was higher in the superobese group, whereas %EWL was similar for the two groups. %EBMIL was higher in less obese patients up to 24 months and similar thereafter. In contrast, %EBMIL with PBMI was greater in the superobese group, although it never reached the 100% goal.
  
  
  CONCLUSIONS
  We conclude that %EBMIL results according to PBMI were not reproducible in our institution. There is a need to elaborate a new easy-to-obtain and reproducible index.
authors.affiliation: Department of Surgery and Anatomy, University Hospital, Faculty of Medicine of Ribeirão Preto, University of São Paulo, R Antônio Chiericato, 760, Ribeirão Preto, São Paulo, 14096 510, Brazil. wsalgado@fmrp.usp.br
authors.forename: Wilson Salgado
authors.initials: WS
authors.lastname: Júnior
authors.forename: Camila Scalassara
authors.initials: CS
authors.lastname: Campos
authors.forename: Carla Barbosa
authors.initials: CB
authors.lastname: Nonino
mesh_terms: D000328:Adult; D050110:Bariatric Surgery / Q000592:standards; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care; D015203:Reproducibility of Results; D012189:Retrospective Studies; D015431:Weight Loss