Burgoine Thomas, Jones Andy P, Namenek Brouwer Rebecca J, Benjamin Neelon Sara E
UKCRC Centre for Diet and Activity Research (CEDAR), MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Box 285 Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK.
Norwich Medical School, University of East Anglia, Norwich, NR4 7TJ, UK.
Int J Health Geogr. 2015 Feb 6;14:8. doi: 10.1186/1476-072X-14-8.
This study examined whether objective measures of food, physical activity and built environment exposures, in home and non-home settings, contribute to children's body weight. Further, comparing GPS and GIS measures of environmental exposures along routes to and from school, we tested for evidence of selective daily mobility bias when using GPS data.
This study is a cross-sectional analysis, using objective assessments of body weight in relation to multiple environmental exposures. Data presented are from a sample of 94 school-aged children, aged 5-11 years. Children's heights and weights were measured by trained researchers, and used to calculate BMI z-scores. Participants wore a GPS device for one full week. Environmental exposures were estimated within home and school neighbourhoods, and along GIS (modelled) and GPS (actual) routes from home to school. We directly compared associations between BMI and GIS-modelled versus GPS-derived environmental exposures. The study was conducted in Mebane and Mount Airy, North Carolina, USA, in 2011.
In adjusted regression models, greater school walkability was associated with significantly lower mean BMI. Greater home walkability was associated with increased BMI, as was greater school access to green space. Adjusted associations between BMI and route exposure characteristics were null. The use of GPS-actual route exposures did not appear to confound associations between environmental exposures and BMI in this sample.
This study found few associations between environmental exposures in home, school and commuting domains and body weight in children. However, walkability of the school neighbourhood may be important. Of the other significant associations observed, some were in unexpected directions. Importantly, we found no evidence of selective daily mobility bias in this sample, although our study design is in need of replication in a free-living adult sample.
本研究探讨了家庭和非家庭环境中食物、身体活动及建成环境暴露的客观测量指标是否会影响儿童体重。此外，通过比较往返学校路线上环境暴露的全球定位系统（GPS）和地理信息系统（GIS）测量结果，我们检验了使用GPS数据时是否存在选择性日常出行偏差的证据。
本研究为横断面分析，采用体重与多种环境暴露的客观评估方法。所呈现的数据来自94名5至11岁学龄儿童的样本。由经过培训的研究人员测量儿童的身高和体重，并用于计算体重指数（BMI）z评分。参与者佩戴GPS设备一周。在家庭和学校周边地区，以及从家到学校的GIS（模型）和GPS（实际）路线上估计环境暴露情况。我们直接比较了BMI与GIS模型和GPS得出的环境暴露之间的关联。该研究于2011年在美国北卡罗来纳州的梅班恩和芒特艾里进行。
在调整后的回归模型中，学校周边更高的步行便利性与显著更低的平均BMI相关。家庭周边更高的步行便利性与BMI升高相关，学校周边更多的绿地可达性也与BMI升高相关。BMI与路线暴露特征之间的调整后关联无统计学意义。在该样本中，使用GPS实际路线暴露似乎并未混淆环境暴露与BMI之间 的关联。
本研究发现家庭、学校和通勤区域的环境暴露与儿童体重之间几乎没有关联。然而，学校周边的步行便利性可能很重要。在观察到的其他显著关联中，有些方向出乎意料。重要的是，我们在该样本中未发现选择性日常出行偏差的证据，尽管我们的研究设计需要在自由生活的成人样本中重复验证。
