Top-Down NOX Emissions of European Cities Based on the Downwind Plume of Modelled and Space-Borne Tropospheric NO2 Columns.

Top-down estimates of surface NOX emissions were derived for 23 European cities based on the downwind plume decay of tropospheric nitrogen dioxide (NO2) columns from the LOTOS-EUROS (Long Term Ozone Simulation-European Ozone Simulation) chemistry transport model (CTM) and from Ozone Monitoring Instrument (OMI) satellite retrievals, averaged for the summertime period (April⁻September) during 2013. Here we show that the top-down NOX emissions derived from LOTOS-EUROS for European urban areas agree well with the bottom-up NOX emissions from the MACC-III inventory data (R² = 0.88) driving the CTM demonstrating the potential of this method. OMI top-down NOX emissions over the 23 European cities are generally lower compared with the MACC-III emissions and their correlation is slightly lower (R² = 0.79). The uncertainty on the derived NO2 lifetimes and NOX emissions are on average ~55% for OMI and ~63% for LOTOS-EUROS data. The downwind NO2 plume method applied on both LOTOS-EUROS and OMI tropospheric NO2 columns allows to estimate NOX emissions from urban areas, demonstrating that this is a useful method for real-time updates of urban NOX emissions with reasonable accuracy.

Polypectomy rate is a valid quality measure for colonoscopy: results from a national endoscopy database.

BACKGROUND: The adenoma detection rate (ADR) is one of the main quality measures for colonoscopy, but it is burdensome to calculate and is not amenable to claims-based reporting. OBJECTIVE: To validate the correlation between polypectomy rates (PRs) and ADRs by using a large group of endoscopists. DESIGN: Retrospective study. SETTING: Community and academic endoscopy units in the United States. SUBJECTS: Sixty endoscopists and their patients. MAIN OUTCOME MEASUREMENTS: Proportion of patients with any adenoma and any polyp removed; correlation between ADRs and PRs. RESULTS: In total, 14,341 screening colonoscopies were included, and there was high correlation between endoscopists' PRs and ADRs in men ( r(s)= .91, P < .0001) and women (r(s) = .91, P < .0001). Endoscopists with PRs in the highest quartile had a significantly higher ADR than did those in the lowest quartile in men (44.6% vs 19.4%, P < .0001) and women (33.6% vs 11.6%, P < .0001). Endoscopists in the top polypectomy quartile also found more advanced adenomas than did endoscopists in the bottom quartile (men: 9.6% vs 4.6%, P = .0006; women: 6.3% vs 3.0%, P = .01). Benchmark PRs of 40% and 30% correlated with ADRs greater than 25% and 15% for men and women, respectively. LIMITATION: Retrospective analysis of a subset of a national endoscopic database. CONCLUSIONS: Endoscopists' PRs correlate well with their ADRs. Given its clinical relevance, its simplicity, and the ease with which it can be incorporated into claims-based reporting programs, the PR may become an important quality measure.

Polypectomy rate as a quality measure for colonoscopy.

BACKGROUND: The adenoma detection rate (ADR) has been proposed as a robust quality indicator for colonoscopy, but it is cumbersome to calculate and not available at the time of colonoscopy. OBJECTIVE: To determine whether endoscopists' polypectomy rates (PRs) correlate with their ADRs and to calculate benchmark PRs that correlate with benchmark ADRs. DESIGN: Retrospective study. SETTING: University and Veterans Affairs endoscopy units in Portland, Oregon. SUBJECTS: Fifteen endoscopists and their patients. MAIN OUTCOME MEASUREMENTS: Proportion of patients with any adenoma and any polyp removed; correlation between ADRs and PRs. RESULTS: Fifteen endoscopists performed 2706 average-risk screening colonoscopies during the study. There was variation in the ADR for men (15.4%-44.7%) and women (6.1%-25.8%) and in the PRs for men (17.9%-66.0%) and women (11.3%-43.1%). Endoscopists' PRs correlated well with their ADRs (r(s) = 0.86, P < .001). To attain the established benchmark ADRs for men (25%) and women (15%), endoscopists needed PRs of 40% and 30%, respectively. Endoscopists attaining the benchmark PRs had a higher ADR among men (32.1% vs 18.4%, P < .001) and a higher ADR among women (21.0% vs 9.8%, P = .01) than those who did not. LIMITATIONS: Study endoscopists' approach to polypectomy may differ from that of endoscopists in other settings. CONCLUSIONS: The PR is a useful quality measure with a high degree of correlation with the ADR.

Colonoscopy reports and current state of performance measures.

Quality improvement of colonoscopy continues to be an important topic. This effort begins with creating detailed and accurate colonoscopy reports. Quality indicators are measurable endpoints that may be used in quality assurance and improvement plans. Key quality measures include cecal intubation rate, adenoma detection, withdrawal time, preparation quality, follow-up recommendations, and American Society of Anesthesiologists classification. Unresolved issues include establishing proper benchmarks, documenting the correlation between process measures and outcomes, aligning incentives to improved quality outcomes, and issues regarding access to quality data.

Racial/ethnic variation in perceptions of medical information sources in Durham County, North Carolina.

BACKGROUND: Concerns about health and health care disparities have led some groups to promote better communication of medical information as a potential means of empowering patients to overcome barriers to health care and to practice healthy behaviors. We examined the independent effect of race/ethnicity on perceptions of the usefulness of different sources of health information. METHODS: We analyzed data from a cross-sectional telephone survey of black, Latino, and white adults (n = 515) in Durham County North Carolina, in 2002. Respondents rated the usefulness of medical information sources, nonmedical information sources, and media. We used logistic regression to determine the effect of race/ethnicity on ratings of information sources, adjusting for demographic, socioeconomic, and health status factors. RESULTS: Compared to white respondents, Latinos and black respondents were more likely to perceive as useful the local health department, ministers/churches, community centers, television, and radio. Latinos were less likely than white and black respondents to report the pharmacy as a useful source of medical information. LIMITATIONS: Some findings may be particular to Durham County, especially those based on the Latino subgroup. Also, the response rate (43%) suggests that nonresponse bias may have affected our results. Finally perceived usefulness may affect one's intent to act on information but may not correlate with the benefit gained from a particular source. CONCLUSIONS: There are substantial racial/ethnic differences in perceptions of certain medical information sources. Medical information designed for minority populations may be more effective if disseminated through particular sources.