The updated pre-test probability model of the 2019 ESC guidelines improves prediction of obstructive coronary artery disease

Introduction and ObjectivesThe 2019 ESC guidelines on chronic coronary syndromes updated the method for estimating the pre-test probability (PTP) of obstructive coronary artery disease (CAD). We aimed to compare the performance of the new PTP method against the 2013 prediction model in patients with stable chest pain undergoing coronary computed tomography angiography (CCTA) for suspected CAD.MethodsWe conducted a single-center cross-sectional study enrolling 320 consecutive patients undergoing CCTA for suspected CAD. Obstructive CAD was defined as any ≥50% luminal stenosis on CCTA. Whenever invasive coronary angiography was subsequently performed, patients were reclassified accordingly. The two PTP prediction models were assessed for calibration, discrimination and the ability to change the downstream diagnostic pathway.ResultsThe observed prevalence of obstructive CAD was 16.3% (n=52). The 2013 prediction model significantly overestimated the likelihood of obstructive CAD (relative overestimation of 130%, p=0.005), while the updated 2019 method showed good calibration (relative underestimation of 6.5%, p=0.712). The two approaches showed similar discriminative power, with C-statistics of 0.73 (95% CI: 0.66-0.80) and 0.74 (95% CI: 0.66-0.81) for the 2013 and 2019 methods, respectively (p=0.933). Reclassification of PTP using the new method resulted in a net reclassification improvement of 0.10 (p=0.001).ConclusionsThe updated 2019 prediction model provides a more accurate estimation of pre-test probabilities of obstructive CAD than the previous model. Adoption of this new score may improve disease prediction and influence the selection of non-invasive testing.     

Are risk factors necessary for pretest probability assessment of coronary artery disease? A patient similarity network analysis of the PROMISE trial

BackgroundPretest probability (PTP) calculators utilize epidemiological-level findings to provide patient-level risk assessment of obstructive coronary artery disease (CAD). However, their limited accuracies question whether dissimilarities in risk factors necessarily result in differences in CAD. Using patient similarity network (PSN) analyses, we wished to assess the accuracy of risk factors and imaging markers to identify ≥50% luminal narrowing on coronary CT angiography (CCTA) in stable chest-pain patients.MethodsWe created four PSNs representing: patient characteristics, risk factors, non-coronary imaging markers and calcium score. We used spectral clustering to group individuals with similar risk profiles. We compared PSNs to a contemporary PTP score incorporating calcium score and risk factors to identify ≥50% luminal narrowing on CCTA in the CT-arm of the PROMISE trial. We also conducted subanalyses in different age and sex groups.ResultsIn 3556 individuals, the calcium score PSN significantly outperformed patient characteristic, risk factor, and non-coronary imaging marker PSNs (AUC: 0.81 vs. 0.57, 0.55, 0.54; respectively, p ?< ?0.001 for all). The calcium score PSN significantly outperformed the contemporary PTP score (AUC: 0.81 vs. 0.78, p ?< ?0.001), and using 0, 1–100 and ?> ?100 cut-offs provided comparable results (AUC: 0.81 vs. 0.81, p ?= ?0.06). Similar results were found in all subanalyses.ConclusionCalcium score on its own provides better individualized obstructive CAD prediction than contemporary PTP scores incorporating calcium score and risk factors. Risk factors may not be able to improve the diagnostic accuracy of calcium score to predict ≥50% luminal narrowing on CCTA.     

《血吸虫病防治知识与行为题库》预试验

目的检验《血吸虫病防治知识与行为题库》（《题库》）编写的科学性、严谨性、可行性、适用性和可理解性,并征求进一步修改和完善的意见与建议。方法随机选择江西和四川两省93名血防专业人员、血吸虫病疫区121名学生和107名成年村民为预试验对象。采用“专题小组讨论”法对《题库》进行预试验。结果认为《题库》具有科学性、严谨性、可行性、适用性和可理解性的预试验对象分别占72.04%、92.47%、68.82%、81.14%和70.13%,同时对某些题项提出修改完善意见。结论《题库》经修改完善后可用于疫区现场血吸虫病健康教育效果调查与评价。     

《血吸虫病健康教育盒》的研制与预试验

目的研制科学、直观、方便、具有针对性的新型血防健康教育材料,并检验其对目标人群的适用性.方法将实物标本和图片有机结合,制作成<血吸虫病健康教育盒>.采用专题小组讨论和把关人咨询两种方法对材料进行预试验.结果根据目标受众信息的需求,采用了主要信息5条:血吸虫病的传播;血吸虫病的危害;儿童血吸虫病的预防;成年妇女血吸虫病的预防;血吸虫病要早检查早治疗.另采用血吸虫病防治的二级信息4条.结论研制的<血吸虫病健康教育盒>可批量制作,供疫区使用.     

Practical utility of clinical prediction rules for suspected acute pulmonary embolism in a large academic institution

INTRODUCTION: In an attempt to standardize clinicians' approach to the determination of pretest probability (PTP) in pulmonary embolism (PE), two simplified scoring models have recently been proposed. We sought to determine the utility of these algorithms in patients with suspected PE in a large, tertiary, academic medical center. METHODS: We performed a retrospective analysis of 295 inpatients and outpatients from our institution who were evaluated for suspected PE. Pretest probability (PTP) was calculated using two previously formulated scoring systems by Wells et al. (Canadian score) and Wicki et al. (Geneva score). Our primary endpoint was the prevalence of PE within each strata of PTP. RESULTS: The prevalence of pulmonary embolism in our cohort was 30%. The prevalence of PE in the low, intermediate and high PTP groups using the Canadian score was 15.3% (95% CI 9.5-23.7%), 34.8% (95% CI 27.9-42.4%), and 47.2% (95% CI 32.0-63.0), respectively. When compared with the low PTP group, the odds ratios of the likelihood of PE was 2.95 (95% CI 1.56-5.59) in the intermediate PTP group and 4.95 (95% CI 2.11-11.64) in the high PTP. The Wicki analysis was divided into "Geneva pure" and "Geneva presumed", where the fractional inspired oxygen concentration was known and presumed to have been sampled on room air, respectively. Neither of the Geneva scores showed statistical significance in the prevalence of PE among the PTP groups. CONCLUSIONS: The Wells' clinical prediction score is easily applied and meaningfully risk stratifies patients with suspected PE. In our population, the Geneva score was less useful.     

Using quantitative methods to improve the diagnostic workup for abdominal pain in children

Introduction

The differential diagnosis of abdominal pain in children can be challenging. We applied quantitative decision-making methods to this process and sought to determine if their use provided measurable benefit.

Methods

After obtaining institutional review board approval, we recorded key elements of the history, physical examination, laboratory, and imaging evaluations along with the cost and the time spent in the emergency department (ED) for children presenting with abdominal pain. Initially, data were collected (group 1, n = 1366 patients) and then presented to the ED pediatricians. For subsequent patients, ED physicians received a sheet specific to that patient's age and sex reporting the most common diagnoses and the elements of the evaluation that had proven most useful (group 2, n = 624 patients). We compared the difference in length of stay and costs before and after intervention, between study groups, by age groups, and separately by sex using a 2-factor analysis of variance.

Results

The diagnostic workup cost less in boys aged 2 to 12 years after the intervention. In boys and girls older than 12 years, the cost trended lower.

Discussion

This study demonstrates that ED physicians equipped with specific information were able to complete their diagnostic evaluation of children presenting with abdominal pain at a lower cost.     

The value of pretest probability and modified clinical pulmonary infection score to diagnose ventilator-associated pneumonia

PURPOSE: The aim of the study was to assess the utility of pretest probability and modified clinical pulmonary infection score CPIS in the diagnosis of late-onset ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: In 740 adults enrolled in a multicenter randomized trial, intensivists prospectively rated the pretest probability of VAP as low, moderate, or high based on their clinical judgment. The modified CPIS was calculated without considering culture results. Ventilator-associated pneumonia diagnosis was determined by 2 adjudicators using standardized definitions. We analyzed the relationship between pretest likelihood, CPIS, and VAP diagnosis. RESULTS: Among the 739 patients analyzed, 14.5%, 39.6%, and 45.9% had low, moderate, and high pretest probability of VAP. Patients with high pretest probability had a lower PaO2/FiO2 ratio and a larger volume of secretions. High or moderate vs low pretest probability had high sensitivity (0.88; 95% confidence interval [CI], 0.87-0.89) and positive predictive value (0.87; 95% CI, 0.86-0.88) but low specificity (0.27; 95% CI, 0.21-0.35) and negative predictive value (0.29; 95% C,: 0.22-0.37) for the diagnosis of VAP. Therefore, 71% of patients who had a low pretest probability were actually infected (1 - negative predictive value). The area under the receiver operating characteristic curve for the modified CPIS was not significant (0.47; 95% CI, 0.42-0.53), meaning that no score threshold was clinically useful. CONCLUSIONS: Pretest probability and a modified CPIS, which excludes culture results, are of limited utility in the diagnosis of late-onset VAP.