scholarly journals How well can screening sensitivity and sojourn time be estimated

2021 ◽  
Vol 53 ◽  
pp. 139-155
Author(s):  
Ayman Hijazy ◽  
András Zempléni
Keyword(s):  
Sojourn Time ◽  
Screening Sensitivity

Estimation of screening sensitivity and sojourn time from an organized screening program

2016 ◽  
Vol 44 ◽  
pp. 178-185 ◽  
Author(s):  
Huan Jiang ◽  
S.D. Walter ◽  
P.E. Brown ◽  
A.M. Chiarelli
Keyword(s):  
Sojourn Time ◽  
Screening Program ◽  
Organized Screening Program ◽  
Screening Sensitivity

Screening Sensitivity and Sojourn Time From Breast Cancer Early Detection Clinical Trials: Mammograms and Physical Examinations

2001 ◽  
Vol 19 (15) ◽  
pp. 3490-3499 ◽  
Author(s):  
Yu Shen ◽  
Marvin Zelen
Keyword(s):  
Breast Cancer ◽  
Clinical Trials ◽  
Cancer Screening ◽  
Early Detection ◽  
Physical Examination ◽  
Breast Cancer Screening ◽  
Sojourn Time ◽  
Screening Programs ◽  
Screening Sensitivity ◽  
Screening Trials

PURPOSE: To estimate sensitivities of breast cancer screening modalities and preclinical duration of the disease from eight breast cancer screening clinical trials. PATIENTS AND METHODS: Screening programs invariably lead to diagnosis of disease before signs or symptoms are present. Two key quantities of screening programs are the sensitivity of the disease detection modality and the mean sojourn time (MST). The observed screening histories in a periodically screened cohort make it possible to estimate these quantities of interest. We applied recently developed statistical methods to data from eight randomized breast cancer screening trials to estimate the sensitivities of early detection modalities and MST. Moreover, when a screening trial involved two screening modalities, our methods enabled the estimation of the individual sensitivity of each screening modality. RESULTS: We analyzed breast cancer data from several screening trials and have relatively complete data from the Health Insurance Plan (HIP), Edinburgh, and two Canadian studies. The screening sensitivity for mammography, physical examination, and MST were, respectively, HIP: 0.39, 0.47, and 2.5 years; Edinburgh: 0.63, 0.40, and 4.3 years; Canadian (age 40 to 49 at entry): 0.61, 0.59, and 1.9 years; Canadian (age 50 to 59 at entry): 0.66, 0.39, and 3.1 years. CONCLUSION: The public debate on early breast cancer detection is mainly centered on mammograms. However, the current study indicates that a physical examination is of comparable importance. Cautious interpretation of trial differences is required as a result of various experimental designs and the age dependency of screening sensitivity and MST.

scholarly journals Estimating mean sojourn time and screening sensitivity using questionnaire data on time since previous screening

2008 ◽  
Vol 15 (2) ◽  
pp. 83-90 ◽  
Author(s):  
Harald Weedon-Fekjær ◽  
Bo H Lindqvist ◽  
Lars J Vatten ◽  
Odd O Aalen ◽  
Steinar Tretli
Keyword(s):  
Sojourn Time ◽  
Questionnaire Data ◽  
Mean Sojourn Time ◽  
Screening Sensitivity

scholarly journals States Transitions Inference of Postpartum Depression Based on Multi-State Markov Model

2021 ◽  
Vol 18 (14) ◽  
pp. 7449
Author(s):  
Juan Xiong ◽  
Qiyu Fang ◽  
Jialing Chen ◽  
Yingxin Li ◽  
Huiyi Li ◽  
...  
Keyword(s):  
Postpartum Depression ◽  
Markov Model ◽  
Normal State ◽  
Sojourn Time ◽  
Transition Probabilities ◽  
Transition Probability ◽  
Public Health Problem ◽  
Mental States ◽  
Hazard Ratio ◽  
Multiple Time

Background: Postpartum depression (PPD) has been recognized as a severe public health problem worldwide due to its high incidence and the detrimental consequences not only for the mother but for the infant and the family. However, the pattern of natural transition trajectories of PPD has rarely been explored. Methods: In this research, a quantitative longitudinal study was conducted to explore the PPD progression process, providing information on the transition probability, hazard ratio, and the mean sojourn time in the three postnatal mental states, namely normal state, mild PPD, and severe PPD. The multi-state Markov model was built based on 912 depression status assessments in 304 Chinese primiparous women over multiple time points of six weeks postpartum, three months postpartum, and six months postpartum. Results: Among the 608 PPD status transitions from one visit to the next visit, 6.2% (38/608) showed deterioration of mental status from the level at the previous visit; while 40.0% (243/608) showed improvement at the next visit. A subject in normal state who does transition then has a probability of 49.8% of worsening to mild PPD, and 50.2% to severe PPD. A subject with mild PPD who does transition has a 20.0% chance of worsening to severe PPD. A subject with severe PPD is more likely to improve to mild PPD than developing to the normal state. On average, the sojourn time in the normal state, mild PPD, and severe PPD was 64.12, 6.29, and 9.37 weeks, respectively. Women in normal state had 6.0%, 8.5%, 8.7%, and 8.8% chances of progress to severe PPD within three months, nine months, one year, and three years, respectively. Increased all kinds of supports were associated with decreased risk of deterioration from normal state to severe PPD (hazard ratio, HR: 0.42–0.65); and increased informational supports, evaluation of support, and maternal age were associated with alleviation from severe PPD to normal state (HR: 1.46–2.27). Conclusions: The PPD state transition probabilities caused more attention and awareness about the regular PPD screening for postnatal women and the timely intervention for women with mild or severe PPD. The preventive actions on PPD should be conducted at the early stages, and three yearly; at least one yearly screening is strongly recommended. Emotional support, material support, informational support, and evaluation of support had significant positive associations with the prevention of PPD progression transitions. The derived transition probabilities and sojourn time can serve as an importance reference for health professionals to make proactive plans and target interventions for PPD.

scholarly journals Pharmacokinetic modeling of Gadolinium nanoparticles (Gd-NPs) with the sojourn time in vasa vasorum for the contrast enhanced MRI

2020 ◽  
Vol 2020 (1) ◽  
Author(s):  
Angkhana Prommarat ◽  
Farida Chamchod
Keyword(s):  
Sojourn Time ◽  
Vasa Vasorum ◽  
Peripheral Arteries ◽  
Resonance Imaging ◽  
Differential Model ◽  
Transfer Rates ◽  
Dynamical Behaviors ◽  
Contrast Enhanced ◽  
Delay Differential

AbstractDeposition of lipid in the artery wall called atherosclerosis is recognized as a major cause of cardiovascular disease that leads to death worldwide. A better understanding into factors that may influence the delivery of gadolinium nanoparticles (Gd-NPs) that enhances quality of magnetic resonance imaging in diagnosis may provide a vital key for atherosclerotic treatment. In this study, we propose a delay differential model for describing the dynamics of Gd-NPs in bloodstream, peripheral arteries, and vasa vasorum with two phenomena of Gd-NPs during a sojourn in vasa vasorum. We then investigate the dynamical behaviors of Gd-NPs and explore the effects of sojourn time and transfer rates of Gd-NPs on the concentration of Gd-NPs in vasa vasorum at the 12th hour after the administration of gadolinium chelates contrast media and also the maximum concentration of Gd-NPs in peripheral arteries and vasa vasorum. Our results suggest that the sojourn of Gd-NPs in vasa vasorum may lead to complex behaviors of Gd-NPs dynamics, and transfer rates of Gd-NPs may have a significant impact on the concentration of Gd-NPs.

Sojourn times and the overtaking condition in Jacksonian networks

1980 ◽  
Vol 12 (04) ◽  
pp. 1000-1018 ◽  
Author(s):  
J. Walrand ◽  
P. Varaiya
Keyword(s):  
Sojourn Time ◽  
Sojourn Times ◽  
Mutually Independent

Consider an open multiclass Jacksonian network in equilibrium and a path such that a customer travelling along it cannot be overtaken directly by a subsequent arrival or by the effects of subsequent arrivals. Then the sojourn times of this customer in the nodes constituting the path are all mutually independent and so the total sojourn time is easily calculated. Two examples are given to suggest that the non-overtaking condition may be necessary to ensure independence when there is a single customer class.

scholarly journals Study on the views and methods of ultrasonic screening and diagnosis for abnormal aortic arch in infants

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xinjian He ◽  
Jiaoyang Chen ◽  
Gaoyang Li
Keyword(s):  
Diagnostic Accuracy ◽  
Aortic Arch ◽  
Subclavian Artery ◽  
Coarctation Of The Aorta ◽  
Double Aortic Arch ◽  
Aberrant Right Subclavian Artery ◽  
Coincidence Rate ◽  
Aortic Arch Anomalies ◽  
Screening Sensitivity ◽  
Axis View

Abstract Background The purpose of this study was to explore echocardiographic views and methods of aortic arch anomalies in infants, so as to improve the screening sensitivity and diagnostic accuracy. Methods 140 children with abnormal aortic arch diagnosed by ultrasound in Children’s Hospital of Hebei Province from January 2014 to December 2019 were selected for retrospective analysis. All were confirmed by surgery or/and computerized tomography angiography. Series of views for aortic arch (the three-vessel and tracheal view, aortic arch short axis view, left aortic arch long axis view, aortic arch long axis continuous scan views) were performed in all cases on the basis of the routine views of echocardiography. The screening sensitivity and diagnostic coincidence rate of different echocardiographic views for aortic arch anomalies were analyzed. Results Among the 140 infants, right aortic arch were 21 cases (6/21 were accompanied by mirror branch and 15/21 were with aberrant left subclavian artery). Left aortic arch with aberrant right subclavian artery were 2 cases, and double aortic arch with both arches open were 20 cases. Double aortic arch with left arch atresia were 2 cases, and atresia of the proximal aorta with aortic arch dysplasia was 1 case. Coarctation of the aorta were 67 cases, and interruption of aortic arch were 27 cases. All the patients were correctly diagnosed except that 2 infants with interruption of aortic arch were incorrectly diagnosed as coarctation of the aorta, and 1 infant with coarctation of the aorta was misdiagnosed as interruption of aortic arch by echocardiography. The screening sensitivities of four views and four-view combination for abnormal aortic arch were 99.3, 73.6, 87.1, 99.3, and 100%; the diagnostic coincidence rates were 85.7, 27.1,66.4, 95.0%, and 97.9% respectively. On the basis of traditional left aortic long axis view, other three views had their own advantages. The screening sensitivity and diagnostic coincidence rate of four-view combination were significantly improved. Conclusions The three-vessel trachea view is simple and feasible, which is suitable for screening abnormal aortic arch. The combination of four views conduces to improving screening sensitivity and diagnostic accuracy of aortic arch abnormalities.

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