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Travel patterns during pregnancy: comparison between Global Positioning System (GPS) tracking and questionnaire data
Jun Wu1, Chengsheng Jiang, Guillermo Jaimes
1Program in Public Health, College of Health Sciences, University of California, Irvine, CA, USA. junwu@uci.edu.
Environmental Health : a Global Access Science Source
|October 11, 2013
Summary
Pregnant women overestimate travel time and distance when reporting travel, impacting air pollution exposure estimates. GPS tracking reveals individual-level differences in particle-bound polycyclic aromatic hydrocarbon (PB-PAH) exposure, crucial for epidemiological studies.
Area of Science:
- Environmental Health
- Epidemiology
- Pregnancy Research
Background:
- Maternal exposure to traffic-related air pollution is linked to adverse pregnancy outcomes.
- Understanding pregnant women's travel patterns is crucial for accurate exposure assessment.
- Reliability of self-reported travel data during pregnancy is largely unknown.
Purpose of the Study:
- To investigate in-vehicle travel behavior of pregnant women.
- To compare travel data from questionnaires versus GPS tracking.
- To assess potential exposure errors in air pollution studies.
Main Methods:
- 56 pregnant women tracked travel using questionnaires and GPS for one week, three times during gestation.
- Compared self-reported trip distance and duration with GPS-derived data.
- Estimated personal exposure to particle-bound polycyclic aromatic hydrocarbon (PB-PAH) and analyzed exposure misclassification.
Main Results:
- Self-reported travel distance and duration were overestimated compared to GPS data.
- GPS and self-reported data showed moderate to high correlations for travel distance and time.
- Daily travel time averaged 69 minutes (GPS) vs. 93 minutes (self-report).
- Individual-level PB-PAH exposure estimates differed significantly between self-reported and GPS data.
Conclusions:
- Self-reported travel data during pregnancy overestimates trip duration and distance.
- Discrepancies in PB-PAH exposure estimates at the individual level are significant.
- These findings have critical implications for epidemiological studies on air pollution and maternal health.
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