title: [Factors determining inappropriate days of stay in a third-level hospital].
abstract: BACKGROUND
  To identify the factors associated with a higher risk of inappropriate days of stay.
  
  
  METHODS
  Crude and adjusted inappropriateness rates were calculated using negative binomial regression to obtain information about the relative risk of each variable. The Appropriateness Evaluation Protocol (AEP) was applied to collect information about patients' hospital stays.
  
  
  RESULTS
  A total of 34.17% (95%CI, 33.28-35.08) of the stays were inappropriate. Women, age older than 65 years, elective admission, and stays in medical services showed the highest inappropriateness risk. Lack of correct patient follow-up in the medical record increased the risk of inappropriateness to 36%.
  
  
  CONCLUSIONS
  Lack of continual registration of the patient's clinical course increased the risk of inappropriate days of stay in the hospital. The use of the negative binomial is a valid and simple option for analysis of this type of phenomenon.
authors.affiliation: Servicio de Medicina Preventiva y Salud Pública, Hospital Clínico Universitario, Valladolid, España. luquero@gmail.com
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Luquero Alcalde
authors.forename: Sara
authors.initials: S
authors.lastname: Santos Sanz
authors.forename: Alberto
authors.initials: A
authors.lastname: Pérez Rubio
authors.forename: Sonia
authors.initials: S
authors.lastname: Tamames Gómez
authors.forename: M Belén
authors.initials: MB
authors.lastname: Cantón Alvarez
authors.forename: Javier
authors.initials: J
authors.lastname: Castrodeza Sanz
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016010:Binomial Distribution; D005260:Female; D006300:Health Services Misuse / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D012306:Risk; D012307:Risk Factors; D012737:Sex Factors; D013030:Spain; D013997:Time Factors