title: [Potential sponsorship bias in cost-effectiveness analyses of healthcare interventions: A cross-sectional analysis].
abstract: OBJECTIVE
  To examine the relationship between the funding source of cost-effectiveness analyses of healthcare interventions published in Spain and study conclusions.
  
  
  METHODS
  Descriptive cross-sectional study.
  
  
  METHODS
  Scientific literature databases (until December 2014).
  Cohort of cost-effectiveness analysis of healthcare interventions published in Spain between 1989-2014 (n=223) presenting quality-adjusted life years (QALYs) as the outcome measure.
  
  
  METHODS
  The relationship between qualitative conclusions of the studies and the type of funding source were established using Fisher's exact test in contingency tables. Distributions of the incremental cost-effectiveness ratios by source of funding in relation to hypothetical willingness to pay thresholds between €30,000-€50,000 per QALY were explored.
  
  
  RESULTS
  A total of 136 (61.0%) studies were funded by industry. The industry-funded studies were less likely to report unfavorable or neutral conclusions than studies non-funded by industry (2.2% vs. 23.0%; P<.0001), largely driven by studies evaluating drugs (0.9% vs. 21.4%; P<.0001). The incremental cost-effectiveness ratios in studies funded by industry were more likely to be below the hypothetical willingness to pay threshold of €30,000 (73.8% vs. 56.3%; P<.0001) and €50,000 (89.4% vs. 68.2%; P<.0001) per QALY.
  
  
  CONCLUSIONS
  This study reveals a potential sponsorship bias in cost-effectiveness analyses of healthcare interventions. Studies funded by industry could be favoring the efficiency profile of their products.
authors.affiliation: Departamento de Medicina, Universidad de Valencia/Instituto de Investigación Sanitaria INCLIVA y CIBERSAM, Valencia, España; Fundación Instituto de Investigación en Servicios de Salud, Valencia, España; Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), Ottawa, Ontario, Canadá. Electronic address: ferran_catala@hotmail.com.
authors.forename: Ferrán
authors.initials: F
authors.lastname: Catalá-López
authors.affiliation: Instituto Aragonés de Ciencias de la Salud (I+CS), Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), Zaragoza, España; FISABIO-Salud Pública, Valencia, España.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ridao
mesh_terms: D015982:Bias; D003362:Cost-Benefit Analysis; D003430:Cross-Sectional Studies; D003695:Delivery of Health Care / Q000191:economics*; D006801:Humans; D013030:Spain
keywords: Años de vida ajustados por calidad; Bias; Cost-effectiveness; Coste-efectividad; España; Quality-adjusted life years; Sesgo; Spain