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1.
A method for computing a measure of tracking based on Cohen's kappa statistic for one-sample longitudinal data sets was previously described and implemented. This paper shows how one may test the equality of several kappas, each computed from an independent longitudinal sample. Thus, it is possible to formally compare groups of individuals with regard to stability in growth (or adaptive) patterns. Relative assessments of predictability in growth outcomes in different populations can be made with this approach. Also, when a common value of kappa is not contradicted by the data, a method to estimate this value and obtain a confidence interval for it is shown. A menu-driven GAUSS program for carrying out the procedure is described and made available. The method and program are illustrated with three samples of Guatemalan children. © 1992 Wiley-Liss, Inc.  相似文献   
2.
Tracking can be defined as the tendency of individuals or collections of individuals to stay within a particular course of growth over time relative to other individuals. Thus, tracking describes stability in growth patterns. This paper outlines a statistical procedure for examining tracking in a single sample of measurements made on humans or other animals. This nonparametric procedure, based on Cohen's (1960) kappa statistic, is suitable for equally or unequally spaced serial data that is complete and is appropriate for questions concerning growth as well as other time-dependent phenomena. It is a conceptually simple longitudinal method that affords insight regarding the predictability of growth within a population. For example, by tracking, one can ask if young children who are in the lowest height for age category are likely to end up in that category at an older age. A user-friendly GAUSS program is provided that generates overall as well as individual and track-specific statistics. High-resolution graphic representations of the data are also generated by the program. Examples are presented, including a tracking analysis of Guatemalan Indian children using quartiles.  相似文献   
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BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers.  相似文献   
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Background:

Rate of coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) varies in different countries. This may be attributable to common transmission routes as well as social, economic, and cultural factors.

Objectives:

The purpose of this study was to investigate the prevalence and risk factors of HCV infection among HIV-positive patients in Istanbul, Turkey.

Patients and Methods:

Since January 2006 to November 2013, 949 HIV-positive patients that were enrolled in this study by ACTHIV-IST (Action Against HIV in Istanbul) Study Group, which consists of five centers to follow up HIV-positive patients in Istanbul. Epidemiologic and clinical data were collected retrospectively from medical records and were transferred to an HIV database system.

Results:

Among 949 patients, 84% were men and the mean age was 37.92 ± 11.54 years (range, 17-79). The most frequent route of transmission was heterosexual intercourse (48.8%), followed by men having sex with men (30.5%). Only nine patients (0.9%) had history of injection drug use (IDU). The prevalence of HIV/HCV coinfection was 0.9% (9:949). The IDU rate was 44.4% (4:9) in patients with HIV/HCV coinfection (three of them were not Turkish citizens), whereas this rate was only 0.6% (5:881) in patients with only HIV infection (P < 0.01). Genotypes 1b, 2a/2c, and 3 were determined in five, one, and two patients, respectively. Genotype could not be determined in one patient. History of residence in a foreign country (P < 0.01) and imprisonment (P < 0.01) were also considered as risk factors in terms of HIV/HCV coinfection.

Conclusions:

Prevalence of HIV/HCV coinfection is considerably low in Turkey. The extremely rare prevalence of IDU might have a role in this low prevalence.  相似文献   
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Helicobacter pylori (HP) is recognized as a common chronic human bacterial infection and is the most common cause of gastritis. Recent studies suggest an increased HP prevalence in patients with various extra-digestive inflammatory diseases. Since many respiratory diseases are characterized by chronic inflammation as well as increased immune response, and HP may enter the nasopharyngeal cavity by gastroesophageal reflux, an association between respiratory disorders and HP infection has been suggested. Several studies discover HP in clinical samples from the patients with upper respiratory system infections. Even some of them revealed a relief after the treatment directed to HP eradication. However some studies do not support this theory and whether this association means a definite proof of a causal relationship between HP and respiratory diseases needs to be clarified. In this study, we aimed to review the reports about the role of HP in upper respiratory system infections.  相似文献   
9.

Background

We investigated the utility of the red cell distribution width (RDW) in diagnosing acute mesenteric ischemia (AMI) in patients with abdominal pain.

Methods

The patients were divided into two groups in this retrospective case–control study: patients with AMI and patients with abdominal pain who did not require urgent surgery. Venous blood was collected from the patients upon admission to the emergency department, and abdominal computed tomography angiography was performed. The RDW and hematological and biochemical parameters of the groups were compared. The primary outcome was AMI among the patients with abdominal pain. The secondary outcome was mortality, complaint period, and size of ischemia/necrosis among the AMI patients.

Results

The RDW, white blood cell lactate dehydrogenase, and blood urea nitrogen of the patients with AMI were significantly different from those of the control group. When the average RDW (15.04 %) of the patients with AMI was used as a cut-off value, the sensitivity, specificity, positive likelihood ratio (+LR), and negative likelihood (?LR) were 40.8 %, 81.2 %, 2.17, and 0.73, respectively. When patients with AMI and anemia were included in the group, the sensitivity and specificity values did not change. There was no relation between the RDW and mortality, size of the ischemia/necrosis, and complaint period. Furthermore, there was no significant difference in the average RDW between the patients with ischemia/necrosis in the small intestine only and those with ischemia/necrosis in the colon.

Conclusion

The RDW on admission is of marginal help to diagnose AMI among patients with abdominal pain.  相似文献   
10.
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