title: Study design for microgravity human physiology experiments.
abstract: In some areas of research, such as microgravity life sciences, both the number of subjects and the opportunity for repeated observation under experimental conditions are limited. Small N study designs are appropriate for these situations since they require few subjects and few observations in the experimental condition. Small N studies compare treatment conditions separately for each subject so that between-subject variability does not obscure treatment effects. Multiple observations are collected for each individual in the baseline condition to ensure a stable reference point for comparison with the smaller number of observations collected under the experimental conditions. Individual differences can be overlooked in large N studies, but in small N studies the focus is on the individual, and differences observed between particular individuals can be suggestive of underlying causal processes. We present a step-by-step approach to designing and conducting a small N study.
authors.affiliation: Microgravity Life Sciences Research Unit, University of British Columbia, University Hospital, Vancouver, Canada.
authors.forename: F A
authors.initials: FA
authors.lastname: Gagnon
authors.forename: L E
authors.initials: LE
authors.lastname: Susak
authors.forename: N
authors.initials: N
authors.lastname: Phillips
authors.forename: P C
authors.initials: PC
authors.lastname: Wing
authors.forename: I K
authors.initials: IK
authors.lastname: Tsang
mesh_terms: D005073:Evoked Potentials, Somatosensory; D006112:Gravitation; D006801:Humans; D010827:Physiology; D012107:Research Design; D013116:Spinal Cord / Q000502:physiology