Section
7
Measuring Body Composition in Population Health Research: Case Studies
Population health research examines health outcomes of groups of individuals and often involves studies that characterize determinants of health and health outcomes as well as factors or interventions that influence health outcomes within and across populations.
As such, it is often conducted in community settings, such as schools, and/or with relatively large samples of participants. In contrast, clinical research focuses on the study of individuals’ risk factors for a health outcome and treatment of individuals and is generally conducted with smaller samples and in settings that offer trained staff and specialized equipment. Compared to clinical research, conducting population health research to assess adiposity in children presents several challenges that can make it difficult to use the most accurate and reliable method. Several other considerations common to all research should also be considered. The first is ensuring the assessment method addresses the study goal. Other general considerations include:
- Parental consent and child assent may be difficult to ascertain if methods carry some risk, feel invasive, or cause embarrassment to the participant, particularly when the methods are conducted by individuals who are not familiar to the child and family.
- Availability of private space or rooms to conduct assessments may be lacking, thus limiting the ability to maintain privacy and confidentiality.
- Examiners may be inexperienced and lack relevant skills and training to work with children.
- Equipment often needs to be portable and durable so that frequent movement does not lead to damage or calibrations errors.
- Specialized equipment needed for some adiposity assessment methods is generally not accessible.
- Environmental conditions, such as temperature and humidity, may not be controllable as is required by some adiposity assessment methods.
- Costs to obtain assessments may be a constraint, including both staff efforts and the financial costs associated with equipment.
The following case studies highlight considerations for population health research. They illustrate how these considerations inform the selection of the most appropriate method(s) for a given scenario based on the research aim or question, the study design, and setting, while taking into consideration various pros and cons of different measurement methods (Table 1) that are relevant to the study.
Regardless of the case scenario or method used in the research, standardization is key to successful implementation and the accurate and reliable collection of data. It is important that the study team use written protocols (i.e., manuals of operation) that instruct staff on the mechanics of obtaining the measurements and that all staff receive a standardized initial training before implementation, and booster trainings during longer term studies. The manuals and staff trainings also should address how to record data and respond to participant questions regarding the measurement process and the participants’ results. Study staff need to be trained to respond to questions in a way that provides accurate information, is consistent across all study staff, maintains participant privacy, and minimizes the potential for participant embarrassment.