title: A Comparison of the Cheater Detection and the Unrelated Question Models: A Randomized Response Survey on Physical and Cognitive Doping in Recreational Triathletes.
abstract: This study assessed the prevalence of physical and cognitive doping in recreational triathletes with two different randomized response models, that is, the Cheater Detection Model (CDM) and the Unrelated Question Model (UQM). Since both models have been employed in assessing doping, the major objective of this study was to investigate whether the estimates of these two models converge.
  
  
  
  An anonymous questionnaire was distributed to 2,967 athletes at two triathlon events (Frankfurt and Wiesbaden, Germany). Doping behavior was assessed either with the CDM (Frankfurt sample, one Wiesbaden subsample) or the UQM (one Wiesbaden subsample). A generalized likelihood-ratio test was employed to check whether the prevalence estimates differed significantly between models. In addition, we compared the prevalence rates of the present survey with those of a previous study on a comparable sample.
  
  
  
  After exclusion of incomplete questionnaires and outliers, the data of 2,017 athletes entered the final data analysis. Twelve-month prevalence for physical doping ranged from 4% (Wiesbaden, CDM and UQM) to 12% (Frankfurt CDM), and for cognitive doping from 1% (Wiesbaden, CDM) to 9% (Frankfurt CDM). The generalized likelihood-ratio test indicated no differences in prevalence rates between the two methods. Furthermore, there were no significant differences in prevalences between the present (undertaken in 2014) and the previous survey (undertaken in 2011), although the estimates tended to be smaller in the present survey.
  
  
  
  The results suggest that the two models can provide converging prevalence estimates. The high rate of cheaters estimated by the CDM, however, suggests that the present results must be seen as a lower bound and that the true prevalence of doping might be considerably higher.
authors.affiliation: Department of Psychology, Eberhard Karls University Tübingen, Tübingen, Germany.|German Institute for Adult Education, Bonn, Germany.
authors.forename: Hannes
authors.initials: H
authors.lastname: Schröter
authors.affiliation: Department of Sports Medicine, Johannes Gutenberg University Mainz, Mainz, Germany.
authors.forename: Beatrix
authors.initials: B
authors.lastname: Studzinski
authors.affiliation: Department of Sports Medicine, Johannes Gutenberg University Mainz, Mainz, Germany.|Department of Physical Activity and Public Health, Karl Franzens University Graz, Graz, Austria.
authors.forename: Pavel
authors.initials: P
authors.lastname: Dietz
authors.affiliation: Department of Psychology, Eberhard Karls University Tübingen, Tübingen, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Ulrich
authors.affiliation: Department of Sports Medicine, Eberhard Karls University Tübingen, Tübingen, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Striegel
authors.affiliation: Department of Sports Medicine, Johannes Gutenberg University Mainz, Mainz, Germany.
authors.forename: Perikles
authors.initials: P
authors.lastname: Simon
mesh_terms: D000328:Adult; D000368:Aged; D004300:Doping in Sports / Q000706:statistics & numerical data*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D015995:Prevalence; D011897:Random Allocation; D011795:Surveys and Questionnaires; D055815:Young Adult