effects of specific equipment on soldier performance. At the same time, it plans to develop new methods to study both cognitive and physical data and to do so in the more realistic environments that are now available. The goal is to use these new metrics to study and understand how physical and cognitive loads impact physical and cognitive performance in activities over an extended period of time.
This group is in a good position to make progress in the next few years. It faces some challenges, many of which it has identified itself:
• Because the world of possible research is vast, the group needs to be strategic in choosing its work. Possibly these choices should be driven by closer contact with infantry and armor operations. More generally, continuing broad collaborative contacts with both the Army and the broader scientific community will help to assure that the research program does not become insular.
• It is obvious that research of this sort requires a steady stream of human volunteer participants. Less obvious is where those human subjects will come from. This is a general HRED issue, but it is particularly salient in the physical and cognitive performance area, because the specialized equipment and facilities require that subjects go to Aberdeen. The group has made some excellent efforts at outreach to different groups of potential subjects, in effect trading participation for benefits that those groups can obtain from the use of HRED facilities. Nevertheless, this is a chronic problem that deserves continuing thought by HRED management.
• Related to both of the preceding points, the group should continue its efforts to study female soldiers, because the patterns of response to physical and cognitive stressors are likely to be different in male and female populations. Male and female may not be the only grouping that should be considered. The potential for other relevant subgroups underlines the need for an ability to recruit substantial numbers of research subjects.
• Here and elsewhere in HRED, more systematic thinking about what constitutes a significant result would be valuable. There are two relevant senses of significance. The first is statistical significance; HRED researchers have been improving markedly in their statistical analyses of data. The second is the significance of the finding to the Army and/or scientific community. Sometimes (as in public health research), very small effects can be both statistically and practically significant. Other times (as occurs quite frequently in cognitive research), it is possible to achieve statistical significance without having much scientific or practical impact. When planning for research in the physical and cognitive performance area, it would be valuable to try to determine how large an effect would be needed to be interesting as either a basic or applied result.
• Some studies appear to terminate without discussion of further research avenues. Ideally, clever, successful, single experiments would give rise to more programmatic series of experiments.
Overall Quality of Research
The research of the physical and cognitive performance interaction research group is generally of high technical quality. To date, its scope has been somewhat limited, but its work may be viewed as preliminary to a successful, coherent program of research based on a developing vision and an excellent suite of deployed experimental platforms.