Prevalence (standard error) of exposure to at least one lifetime PTE was 73.8% (1.15) in the total sample, while the average person exposed to any lifetime PTE reported an average of 4.3 occurrences, for a total of approximately 13,700 lifetime PTEs experienced by the 4,315 SASH respondents (Table 1).
Two independent reviewers assessed the methodological quality of included studies, examining selection methods, missing data, loss-to-follow-up, misclassification or measurement errors of exposures or outcomes, and confounding bias.
There are several general problems in environmental epidemiology : long latent periods, low-level exposures, errors of exposure measurement, small effects….
Measurement errors of exposure to air pollution and potential confounders usually exist in air pollution epidemiological studies and it is impossible to be solved in most air pollution studies [ 66].
Because the questionnaires are administered at the same time in a cross-sectional study and relied on respondent recall, the measurement errors of exposure (that is, alcohol consumption) may be dependent on the measurement errors of the outcomes (that is, quality of life or FM symptoms).
Correction for multiple comparisons and the measurement error of environmental exposures also influence study power [ 1, 2].
First, the availability and accuracy of different geocoding techniques may vary among countries, as well as the resolution of the exposure model (upon which the impact of geocoding errors on exposures will depend).
19 "compliance with the intervention" was replaced by "avoidance of misclassification error of the exposure".
The stronger effect occurred because of the regression dilution bias and a reduction in the measurement error of PM2.5 exposure from using multiple days (MacMahon et al. 1990).
