8 research outputs found
Department and worker characteristics of the analyzed population.
<p>Data are median (IQR) and n (%) unless otherwise indicated.</p><p>TTHā=ātension-type headache, Mā=āmigraine, MPā=āmyogenous neck/shoulder pain.</p
Effects of the intervention (change from baseline in the number of days with pain or drug consumption at month 7) on the study outcomes.
<p>*Adjusted by age, sex, neck/shoulder pain (when analyzing headache and analgesic drug consumption), headache (when analyzing neck/shoulder pain and analgesic drug consumption), education level, and job activity.</p
Mean differences (days/month) between groups in the changes from baseline (month 7 vs. month 1) of the frequency of headache (panel A), neck/shoulder pain (panel B), headache and/or neck/shoulder pain (panel C), by subgroups.
<p>Mean differences (days/month) between groups in the changes from baseline (month 7 vs. month 1) of the frequency of headache (panel A), neck/shoulder pain (panel B), headache and/or neck/shoulder pain (panel C), by subgroups.</p
Comparison of the proportion of subjects with (āimprovedā<sup>*</sup>) or without (ānot improvedā <sup>ā”</sup>) reduction in pain frequency or drug consumption of ā„50% at the end of follow-up (responder rates), between IG and control group.
<p>*āImprovedā: subjects with a baseline frequency of ā„4 days/month with pain (or drug consumption) that had a reduction in pain frequency or drug consumption of ā„50% at the end of follow-up.</p>ā”<p>āNot improvedā: includes subjects with ā„4 days/month with pain (or drug consumption) at the baseline with less than 50% of reduction in pain frequency or drug consumption at the end of follow-up, and those subjects that had a baseline frequency of less than 4 days with pain/drug consumption independently from their results.</p>Ā§<p>adjusted by age, sex, neck/shoulder pain (when analyzing headache and analgesic drug consumption), headache (when analyzing neck/shoulder pain and analgesic drug consumption), education level, job activity and baseline value of each subject.</p
Results (responder rates) of the sensitivity analyses performed on the whole randomized population according to two different <i>scenarios</i>.
<p>*Scenario 1: the probability of improvement observed in the control group was assigned to the workers not completing the baseline and/or the follow-up diary in both the IG and the control group.</p><p>**Scenario 2 (<i>worst scenario</i>): the probability of improvement observed in the IG was assigned to the workers not completing the baseline and/or the follow-up diary in the control group, whereas the probability of improvement observed in the control group was assigned to the workers not completing the baseline and/or the follow-up diary in the IG.</p
Evaluation of Land Use Regression Models for NO<sub>2</sub> and Particulate Matter in 20 European Study Areas: The ESCAPE Project
Land use regression models (LUR)
frequently use leave-one-out-cross-validation
(LOOCV) to assess model fit, but recent studies suggested that this
may overestimate predictive ability in independent data sets. Our
aim was to evaluate LUR models for nitrogen dioxide (NO<sub>2)</sub> and particulate matter (PM) components exploiting the high correlation
between concentrations of PM metrics and NO<sub>2</sub>. LUR models
have been developed for NO<sub>2</sub>, PM<sub>2.5</sub> absorbance,
and copper (Cu) in PM<sub>10</sub> based on 20 sites in each of the
20 study areas of the ESCAPE project. Models were evaluated with LOOCV
and āhold-out evaluation (HEV)ā using the correlation
of predicted NO<sub>2</sub> or PM concentrations with measured NO<sub>2</sub> concentrations at the 20 additional NO<sub>2</sub> sites
in each area. For NO<sub>2</sub>, PM<sub>2.5</sub> absorbance and
PM<sub>10</sub> Cu, the median LOOCV <i>R</i><sup>2</sup>s were 0.83, 0.81, and 0.76 whereas the median HEV <i>R</i><sup>2</sup> were 0.52, 0.44, and 0.40. There was a positive association
between the LOOCV <i>R</i><sup>2</sup> and HEV <i>R</i><sup>2</sup> for PM<sub>2.5</sub> absorbance and PM<sub>10</sub> Cu.
Our results confirm that the predictive ability of LUR models based
on relatively small training sets is overestimated by the LOOCV <i>R</i><sup>2</sup>s. Nevertheless, in most areas LUR models still
explained a substantial fraction of the variation of concentrations
measured at independent sites
Development of Land Use Regression Models for PM<sub>2.5</sub>, PM<sub>2.5</sub> Absorbance, PM<sub>10</sub> and PM<sub>coarse</sub> in 20 European Study Areas; Results of the ESCAPE Project
Land Use Regression (LUR) models have been used increasingly
for
modeling small-scale spatial variation in air pollution concentrations
and estimating individual exposure for participants of cohort studies.
Within the ESCAPE project, concentrations of PM<sub>2.5</sub>, PM<sub>2.5</sub> absorbance, PM<sub>10</sub>, and PM<sub>coarse</sub> were
measured in 20 European study areas at 20 sites per area. GIS-derived
predictor variables (e.g., traffic intensity, population, and land-use)
were evaluated to model spatial variation of annual average concentrations
for each study area. The median model explained variance (<i>R</i><sup>2</sup>) was 71% for PM<sub>2.5</sub> (range across
study areas 35ā94%). Model <i>R</i><sup>2</sup> was
higher for PM<sub>2.5</sub> absorbance (median 89%, range 56ā97%)
and lower for PM<sub>coarse</sub> (median 68%, range 32ā 81%).
Models included between two and five predictor variables, with various
traffic indicators as the most common predictors. Lower <i>R</i><sup>2</sup> was related to small concentration variability or limited
availability of predictor variables, especially traffic intensity.
Cross validation <i>R</i><sup>2</sup> results were on average
8ā11% lower than model <i>R</i><sup>2</sup>. Careful
selection of monitoring sites, examination of influential observations
and skewed variable distributions were essential for developing stable
LUR models. The final LUR models are used to estimate air pollution
concentrations at the home addresses of participants in the health
studies involved in ESCAPE