scholarly journals A method of assessing the sensitivity of the Cochran–Mantel–Haenszel test to an unobserved confounder

2008 ◽  
Vol 366 (1874) ◽  
pp. 2377-2388 ◽  
Author(s):  
Binbing Yu ◽  
Joseph L Gastwirth
Keyword(s):  
Sensitivity Analysis ◽  
Observational Studies ◽  
Control Design ◽  
Computer Code ◽  
Case Control ◽  
Low Birth Weight Infants ◽  
Erroneous Conclusion ◽  
Maternal Hypertension ◽  
Haenszel Test ◽  
Causal Variables

Observational studies, including the case-control design frequently used in epidemiology, are subject to a number of biases and possible confounding factors. Failure to adjust with them may lead to an erroneous conclusion about the existence of a causal relationship between exposure and disease. The Cochran–Mantel–Haenszel (CMH) test is widely used to measure the strength of the association between an exposure and disease or response, after stratifying on the observed covariates. Thus, observed confounders are accounted for in the analysis. In practice, there may be causal variables that are unknown or difficult to obtain. Hence, they are not incorporated into the analysis. Sensitivity analysis enables investigators to assess the robustness of the findings. A method for assessing the sensitivity of the CMH test to an omitted confounder is presented here. The technique is illustrated by re-examining two datasets: one concerns the effect of maternal hypertension as a risk factor for low birth weight infants and the other focuses on the risk of allopurinol on having a rash. The computer code performing the sensitivity analysis is provided in appendix A.

scholarly journals General concepts in biostatistics and clinical epidemiology: observational studies with case-control design

Medwave ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. e7716-e7716
Author(s):  
Diego Martínez ◽  
Cristian Papuzinski ◽  
Jana Stojanova ◽  
Marcelo Arancibia
Keyword(s):  
Observational Studies ◽  
Clinical Epidemiology ◽  
Control Design ◽  
Case Control

An adaptive Mantel-Haenszel test for sensitivity analysis in observational studies

Biometrics ◽  
2016 ◽  
Vol 73 (2) ◽  
pp. 422-430 ◽  
Author(s):  
Paul R. Rosenbaum ◽  
Dylan S. Small
Keyword(s):  
Sensitivity Analysis ◽  
Observational Studies ◽  
Haenszel Test

scholarly journals 688 Pediatric Obstructive Sleep Apnea (OSA) and COVID-19-Related Adverse Clinical Outcomes

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A269-A269
Author(s):  
Vaishal Shah ◽  
Nancy Foldvary-Schaefer ◽  
Lu Wang ◽  
Lara Jehi ◽  
Cynthia Pena Obrea ◽  
...  
Keyword(s):  
High Risk ◽  
Clinical Outcome ◽  
Clinical Outcomes ◽  
Pediatric Patients ◽  
Control Design ◽  
Supplemental Oxygen ◽  
Case Control ◽  
World Health ◽  
Invasive Ventilation ◽  
High Flow Oxygen

Abstract Introduction The relationship of OSA and human coronavirus (COVID-19) in the pediatric population is unknown. We postulate that OSA is associated with SARS-CoV-2 positivity and with adverse COVID-19 outcomes in children. Methods A retrospective review of 120 consecutive patients (<18 years) with prior polysomnogram (PSG) and COVID-19 testing from the Cleveland Clinic COVID-19 registry was conducted. Using a case control design of SARS-CoV-2 positive and negative pediatric patients, we examined COVID-19 and pre-existing OSA (dichotomized AHI≥1) using logistic (OR,95%CI) regression and as continuous measures: AHI, oxygen(SpO2) nadir, %time SpO2<90%) using linear regression(beta+/-SE). In those positive for SARS-CoV-2(cases only), we assessed the association of OSA and World Health Organization(WHO) COVID-19 clinical outcome composite score (hospitalization, requiring supplemental oxygen, non-invasive ventilation/high-flow oxygen, invasive ventilation/ECMO or death) using Wilcoxon rank sum test for ordinal data. Results Cases (n=36) were 11.8±4.4 years, 61% male, 27.8% black and 88.9% with OSA, while 85.7% of controls (n=84) had OSA. OSA was not associated with increased SARS-CoV-2 positivity: OR=1.33(0.40, 4.45,p=0.64). No significant difference between cases and controls for mean AHI 3.7(1.5,6.0) vs 3.5(1.5,7.1),p=0.91,SpO2 nadir 88.6±5.4 vs 89.1±4.4,p=0.58,%time SpO2<90% 0.05[0.00,1.00) vs 0.10 (0.00,1.00, p=0.65) respectively was noted. WHO-7 COVID-19 clinical outcome did not meet statistical significance in relation to OSA due to the low event frequency (p=0.49). Of note, those with OSA vs without OSA had a higher WHO-7 outcome score of 2 vs 0 and prevalence of hospitalization: 12.5 vs 0% respectively. Of hospitalized patients, the following was observed: 23% had moderate/severe OSA vs 4.3% mild OSA, 50% required supplemental oxygen and 25% required intubation/invasive ventilation. No deaths or readmissions were reported. High risk conditions included: 75% obesity, 50% asthma, 25% sickle cell disease and 25% hypoplastic left heart. Conclusion In this first report of which we are aware focused on COVID-19 in pediatric OSA, we use a case control design leveraging COVID-19 and sleep laboratory registries. Albeit not statistically significant, pediatric patients with OSA had a higher percentage of worse clinical outcomes. Larger network studies are needed to clarify whether poorer COVID-19 outcomes may be attributable to OSA or modulated via high risk health conditions. Support (if any):

Depressive Symptoms in Comorbid Obstructive Sleep Apnea and Insomnia: An Integrative Review

2021 ◽  
pp. 019394592198965
Author(s):  
Bomin Jeon ◽  
Faith S. Luyster ◽  
Judith A. Callan ◽  
Eileen R. Chasens
Keyword(s):  
Obstructive Sleep Apnea ◽  
Depressive Symptoms ◽  
Sleep Apnea ◽  
Control Design ◽  
Case Control ◽  
Integrative Review ◽  
Study Quality ◽  
Cross Sectional ◽  
Obstructive Sleep ◽  
The Relationship

The purpose of this integrative review was to synthesize evidence concerning the relationship between comorbid obstructive sleep apnea and insomnia (OSA+I), and depressive symptoms. OSA and insomnia are common sleep disorders, recently comorbid OSA+I has been recognized as prevalent in adults. Although each sleep disorder increases the risk and severity of depressive symptoms, the effect of comorbid OSA+I on depressive symptoms remains unclear. A systematic search of PubMed, CINAHL, and PsycINFO identified 15 data-based studies. All the studies were observational with either a cross-sectional (n = 14) or a case-control design (n = 1). Study quality was assessed. Most of the studies (n = 14) indicated that comorbid OSA+I had an additive role on depressive symptoms. Insomnia appeared to have a more important role than OSA in increasing the severity of depressive symptoms in persons with comorbid OSA+I.

scholarly journals Radioprotective Effect of Hesperidin: A Systematic Review

Medicina ◽  
2019 ◽  
Vol 55 (7) ◽  
pp. 370 ◽  
Author(s):  
Musa ◽  
Omyan ◽  
Esmaely ◽  
Shabeeb
Keyword(s):  
Clinical Trials ◽  
Survival Rates ◽  
Control Design ◽  
Case Control ◽  
Radioprotective Effect ◽  
Cellular Damage ◽  
Animal Cells ◽  
Meta Analyses ◽  
Late Side ◽  
Radioprotective Agent

Background and objectives: Ionizing radiation (IR) has been of immense benefit to man, especially for medical purposes (diagnostic imaging and radiotherapy). However, the risks of toxicity in healthy normal cells, leading to cellular damage as well as early and late side effects, have been major drawbacks. The aim of this study was to evaluate the radioprotective effect of hesperidin against IR-induced damage. Materials and Methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) were applied in reporting this study. A search was conducted using the electronic databases PubMed, Scopus, Embase, Google Scholar, and www.ClinicalTrials.gov for information about completed or ongoing clinical trials. Results: From our search results, 24 studies involving rats, mice, and cultured human and animal cells were included. An experimental case—control design was used in all studies. The studies showed that the administration of hesperidin reduced oxidative stress and inflammation in all investigated tissues. Furthermore, it increased 30-day and 60-day survival rates and protected against DNA damage. The best radioprotection was obtained when hesperidin was administered before irradiation. Conclusions: The results of the included studies support the antioxidant, anti-inflammatory, and antiapoptotic abilities of hesperidin as a potential radioprotective agent against IR-induced damage. We recommend future clinical trials for more insights.

Soy Consumption with Risk of Coronary Heart Disease and Stroke: A Meta-Analysis of Observational Studies

2016 ◽  
Vol 46 (4) ◽  
pp. 242-252 ◽  
Author(s):  
Danfei Lou ◽  
Yuehua Li ◽  
Guoliang Yan ◽  
Jianhong Bu ◽  
Haihui Wang
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Cohort Studies ◽  
Observational Studies ◽  
Meta Analysis ◽  
Case Control ◽  
Inverse Association ◽  
Case Control Studies ◽  
Relative Risks ◽  
Product Consumption

Background: The association of soy product consumption with the relative risk of cardiovascular disease remains controversial. This meta-analysis aimed at investigating whether an association exists between soy consumption and the risk of stroke and coronary heart disease (CHD) in observational studies. Methods: A systematic search of the PubMed and EMBASE databases was performed for case-control and cohort studies that assessed soy consumption and the risk of stroke and CHD. Summary relative risks (SRRs) and 95% CIs were combined by using a random-effects model. Results: Of a total of 1,266 abstracts, 5 prospective cohort and 6 case-control studies met our inclusion criteria, and comprised 4,954 stroke and 7,616 CHD events. Based on the high vs. low analyses, combining cohort studies showed no association between soy intake and risk of stroke (SRR 0.92; 95% CI 0.70-1.10; Pheterogeneity = 0.236; I2 = 29.4%) or CHD (SRR 0.97; 95% CI 0.74-1.27; Pheterogeneity = 0.020; I2 = 62.7%), although a significantly inverse association between soy intake and the risk of stroke (SRR 0.54; 95% CI 0.34-0.87; Pheterogeneity = 0.001; I2 = 79.3%) and CHD (SRR 0.66; 95% CI 0.56-0.77; Pheterogeneity = 0.421; I2 = 0) was observed in case-control studies. No association between soy isoflavone intake and the risk of stroke and CHD was identified. Conclusion: There was limited evidence to indicate that soy consumption was inversely associated with the risk of stroke and CHD, although further studies, with prospective designs that use validated questionnaires and control for important confounders, are warranted.

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