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. 2009 Nov 30;4(11):e7824.
doi: 10.1371/journal.pone.0007824.

Survey of the Quality of Experimental Design, Statistical Analysis and Reporting of Research Using Animals

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Survey of the Quality of Experimental Design, Statistical Analysis and Reporting of Research Using Animals

Carol Kilkenny et al. PLoS One. .
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For scientific, ethical and economic reasons, experiments involving animals should be appropriately designed, correctly analysed and transparently reported. This increases the scientific validity of the results, and maximises the knowledge gained from each experiment. A minimum amount of relevant information must be included in scientific publications to ensure that the methods and results of a study can be reviewed, analysed and repeated. Omitting essential information can raise scientific and ethical concerns. We report the findings of a systematic survey of reporting, experimental design and statistical analysis in published biomedical research using laboratory animals. Medline and EMBASE were searched for studies reporting research on live rats, mice and non-human primates carried out in UK and US publicly funded research establishments. Detailed information was collected from 271 publications, about the objective or hypothesis of the study, the number, sex, age and/or weight of animals used, and experimental and statistical methods. Only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used. Appropriate and efficient experimental design is a critical component of high-quality science. Most of the papers surveyed did not use randomisation (87%) or blinding (86%), to reduce bias in animal selection and outcome assessment. Only 70% of the publications that used statistical methods described their methods and presented the results with a measure of error or variability. This survey has identified a number of issues that need to be addressed in order to improve experimental design and reporting in publications describing research using animals. Scientific publication is a powerful and important source of information; the authors of scientific publications therefore have a responsibility to describe their methods and results comprehensively, accurately and transparently, and peer reviewers and journal editors share the responsibility to ensure that published studies fulfil these criteria.

Conflict of interest statement

Competing Interests: Dr Michael Festing was a member of the NC3Rs Board from September 2004 to July 2007. Members of the NC3Rs board are not remunerated. In addition Dr Festing would like to declare that he teaches short courses on the design and statistical analysis of animal experiments to scientists who are applicants for Home Office licences, for which he is paid. There are no competing interests for any of the other authors.


Figure 1
Figure 1. Flow diagram summarising the survey methods.

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