Beyond the Lab Coat: Methodological Challenges in Space Life Sciences

Martine Van Puyvelde^1,2,3*Nicholas H van den Berg^1,4Lara Stas⁵Perseverence Savieri^5,6Hortense Corlùy^1,7Jeroen Van Cutsem^1,7Xavier Neyt¹Guido Simonelli^4,8,9Nathalie Pattyn^1,10,4

• ¹LIFE-VIPER, Royal Military Academy, Brussels, Belgium
• ²Brain, Body and Cognition, Faculty of Psychology and Educational Sciences,, Vrije Universiteit Brussel, Brussels, Belgium
• ³School of Natural Sciences & Psychology, Faculty of Science, Liverpool John Moores University, Liverpool, United Kingdom
• ⁴Center for Advanced Research in Sleep Medicine, Hopital du Sacre-Coeur de Montreal, Montreal, Canada
• ⁵Core Facility-Support for Quantitative and Qualitative Research, Vrije Universiteit Brussel, Brussels, Belgium
• ⁶Research Center for Digital Medicine Research Group, Vrije Universiteit Brussel Faculty of Medicine, Brussels, Belgium
• ⁷Human Physiology and Sports Physiotherapy Research Group, Vrije Universiteit Brussel, Brussels, Belgium
• ⁸Department of Medicine, Faculty of Medicine, Universite de Montreal, Montreal, Canada
• ⁹Department of Neuroscience, Faculty of Medicine, Université de Montreal, Montreal, Canada
• ¹⁰Department of Medicine, Faculty of Medicine, Université de Montreal, Montreal, Canada

As plans for deep space and long-duration missions advance, research in space and space-analog environments is becoming an urgent scientific priority. However, this type of fieldwork poses a unique set of challenges. The development of research methodologies and designs cannot rely on broad evidence base and thus requires scientific judgment and multidisciplinary psychophysiological expertise. Most studies comprise small samples, often lack control groups, sex differences have seldom been directly tested in this area and inter-individual variability is prevalent in this population. Moreover, this research domain is characterized by several exceptional factors that must be addressed. The target population is highly trained and not representative of the general population, demanding adapted study designs and highly sensitive and operationally relevant research tools. To avoid overburdening the already heavy operational schedules of this population, a careful and feasible balance must be established between scientific data quality and acceptable monitoring load. Furthermore, several issues of location, timing, and type of baseline measures must be explicitly considered, while long-term follow-up designs are necessary to assess both recovery and persistent post-mission effects. Major space agencies have indeed identified methodological issues as a knowledge gap in this area. In this review, we provide an overview of these methodological challenges unique to space life sciences and offer solutions where possible. We argue that space research remains feasible despite these constraints, but only when it is approached with the understanding that such fieldwork often requires fundamentally different methods than traditional laboratory science.