Automated calculation of the right ventricle to left ventricle ratio on CT for the risk stratification of patients with acute pulmonary embolism.

OBJECTIVES: To assess the feasibility and reliability of the use of artificial intelligence post-processing to calculate the RV:LV diameter ratio on computed tomography pulmonary angiography (CTPA) and to investigate its prognostic value in patients with acute PE. METHODS: Single-centre, retrospective study of 101 consecutive patients with CTPA-proven acute PE. RV and LV volumes were segmented on 1-mm contrast-enhanced axial slices and maximal ventricular diameters were derived for RV:LV ratio using automated post-processing software (IMBIO LLC, USA) and compared to manual analysis in two observers, via intraclass coefficient correlation analysis. Each CTPA report was analysed for mention of the RV:LV ratio and compared to the automated RV:LV ratio. Thirty-day all-cause mortality post-CTPA was recorded. RESULTS: Automated RV:LV analysis was feasible in 87% (n = 88). RV:LV ratios ranged from 0.67 to 2.43, with 64% (n = 65) > 1.0. There was very strong agreement between manual and automated RV:LV ratios (ICC = 0.83, 0.77-0.88). The use of automated analysis led to a change in risk stratification in 45% of patients (n = 40). The AUC of the automated measurement for the prediction of all-cause 30-day mortality was 0.77 (95% CI: 0.62-0.99). CONCLUSION: The RV:LV ratio on CTPA can be reliably measured automatically in the majority of real-world cases of acute PE, with perfect reproducibility. The routine use of this automated analysis in clinical practice would add important prognostic information in patients with acute PE. KEY POINTS: • Automated calculation of the right ventricle to left ventricle ratio was feasible in the majority of patients and demonstrated perfect intraobserver variability. • Automated analysis would have added important prognostic information and altered risk stratification in the majority of patients. • The optimal cut-off value for the automated right ventricle to left ventricle ratio was 1.18, with a sensitivity of 100% and specificity of 54% for the prediction of 30-day mortality.

Household-level spatiotemporal patterns of incidence of cholera, Haiti, 2011.

A cholera outbreak began in Haiti during October, 2010. Spatiotemporal patterns of household-level cholera in Ouest Department showed that the initial clusters tended to follow major roadways; subsequent clusters occurred further inland. Our data highlight transmission pathway complexities and the need for case and household-level analysis to understand disease spread and optimize interventions.

The medium can influence the message: Print-based versus digital reading influences how people process different types of written information.

While electronic reading devices are extremely popular, research is equivocal regarding their benefits for outcomes such as reader comprehension. Integrating literatures on reading medium comparisons and matching effects in persuasion, this research tested whether comprehension is maximized when the content of the material (e.g., whether it is traditional vs. modern) matches the medium (e.g., reading from a traditional book vs. digital e-reader). In Study 1, participants read a traditional- or modern-themed short story from either a book or an e-reader. Story comprehension was greater when participants read from the printed medium compared to the e-reader, an effect that was marginally moderated by story content, consistent with a matching effect. In Study 2, participants read a persuasive message that emphasized either a traditional versus modern solution to improving health in either a magazine format or on an iPad. Message comprehension was marginally greater among participants who read their message in a printed format. Participants' interest in weight loss showed evidence of a matching effect - participants were more interested in losing weight when a modern solution to obesity article was presented on an iPad compared to a printed format. The results are applied to the study of reading and attitude change.