No clear trends in expatriation of non-human primate research from ­Switzerland between 2004 and 2017

INTRODUCTION Animal experimentation is commonly practiced in scientific research worldwide. However, there are no globally accepted standards for regulating the ethical boundaries and accepted practices for animal experimentation. Large differences exist between countries. A report suggested that some researchers, especially from countries with more stringent animal experimentation regulations, may be relocating experimental research to countries with less stringent regulations. We followed a systematic literature review approach to identity publications and determine whether there is an increasing trend in expatriation of non-human primate experimentation by researchers based in Switzerland. We used the Projects People Publications database, which contains projects funded by the Swiss National Science Foundation, to identify researchers conducting experiments using non-human primates. This list of names, together with terms referring to non-human primates were used to search the Web of Science. Publications without an author affiliated to a Swiss institution, no living or only with free non-human primates, and non-original research were excluded. For each publication, we recorded the place of experimentation, funding source, number of animals, species and the statement of ethical approval. We retained 120 publications, involving more than 2,429 non-human primates. Macaca mulatta and Macaca fascicularis were the most common species. We could not confirm an increasing trend in expatriation of non-human primate experimentation outside of Switzerland. Over time, publications appeared to report the ethical approval number more consistently. These results should be interpreted with caution because the sample included only studies that were: 1) published and 2) reported in the Web of Science. Consequently, studies with insignificant results may have been excluded because these studies are rarely published, and studies of poor quality may have been excluded because they are often published in lower quality journals, not indexed by the Web of Science.