title: [Internal quality assurance or Hawthorne effect?].
abstract: The tendency of study participation per se to affect outcome is described by the term Hawthorne effect. This process defines the first step for internal quality assurance. However, whenever an attempt is made to describe the effects of quality assurance in more detail specific mathematical tools are required, including a database system that allows the calculation of clinical profiles, problem profiles, time-related variance of variables, univariate and multivariate statistics, calculation of scores and application of the hazard function. However, it has to be considered that any mathematical model is a way to present a hypothesis and not a proof. Whenever a proof is required, one should not ask for internal quality assurance, but design a randomized study.
authors.affiliation: Klinik für Herzchirurgie, Universität Heidelberg.
authors.forename: C F
authors.initials: CF
authors.lastname: Vahl
authors.forename: B R
authors.initials: BR
authors.lastname: Osswald
authors.forename: P
authors.initials: P
authors.lastname: Meinzer
authors.forename: R
authors.initials: R
authors.lastname: de Simone
authors.forename: G
authors.initials: G
authors.lastname: Thomas
authors.forename: S
authors.initials: S
authors.lastname: Hagl
mesh_terms: D006348:Cardiac Surgical Procedures / Q000191:economics*; D001026:Coronary Artery Bypass / Q000191:economics; D003362:Cost-Benefit Analysis; D003625:Data Collection; D003628:Database Management Systems; D006801:Humans; D008962:Models, Theoretical; D010043:Outcome and Process Assessment, Health Care; D017410:Practice Guidelines as Topic; D011785:Quality Assurance, Health Care / Q000191:economics*
vernacular_title: Interne Qualitätssicherung oder Hawthorne-Effekt?