geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Bias from nondifferential misclassification in case-control studies with three exposure levels


, : Bias from nondifferential misclassification in case-control studies with three exposure levels. Epidemiology 6(3): 276-281

In case-control studies with three exposure levels where disease risk is associated with exposure, the direction of bias in the odds ratios (ORs) from nondifferential misclassification depends on the risk level, misclassification rates, and exposure distributions. To extend these generalizations, we present a graphical analysis of bias from nondifferential misclassification assuming linear and nonlinear monotonic increasing exposure-risk patterns. In both middle and upper exposure levels, bias is usually toward the null, increasing in magnitude as the misclassification rates increase and as the skewness of the exposure distribution increases. In the middle exposure level, bias away from the null may occur when the misclassification rate is low in the reference level and moderate to high in the upper exposure level, and risk increases with exposure. Bias away from the null does not occur in the upper exposure level. In both excess risk levels, crossover bias (that is, a reversal of the OR) may occur when exposure classification is worse than chance. The magnitude of bias away from the null is constrained by the unbiased OR of the upper exposure level, whereas that of crossover bias is constrained by the inverse of the unbiased OR of the upper exposure level.

US$29.90

PMID: 7619936


Other references

Cefai, D.; Morrison, B.W.; Sckell, A.; Favre, L.; Balli, M.; Leunig, M.; Gimmi, C.D., 1999: Targeting HER-2/neu for active-specific immunotherapy in a mouse model of spontaneous breast cancer. The identification of tumor-associated antigens has led to increased interest in vaccination strategies to treat and/or prevent cancer. This study examined the feasibility of active-specific immunotherapy against the breast-tumor antigen HER-2/neu...

Tölg, Günther.; Fresenius, W., 2005: My memories of Professor Wilhelm Fresenius. Analytical and Bioanalytical Chemistry 382(8): 1733-1737

Clement, K., 2010: Solomon Islands Experience Holiday with a Heart. Him Journal 39(3): 60-63

Parshikova, T.; Negrutsky, S., 1988: Influence of surfactants on algae. (Review). Gidrobiologicheskii Zhurnal 24(6): 46-58

Yu-Wei; Wu-Ji-Liang; Wang-Hui; Zha-Wen-Liang, 2005: Protective effect of garlic polysaccharide on cardiac myocyte injury by adriamycin. Aim To observe the protective effects and its mechanisms of Garlic Polysaccharide(GP) on toxic cardiac myocyte induced by adriamycin (ADR). Methods Primary culture neonatal SD rat cardiac myocyte and ADR injury model were established. The activiti...

Abbott, Waldo G., 1966: Little blue heron at Santa Barbara, California. Condor 68(1): 103

Smith, C.A.; Douglas, S.D.; Greene, J.M.; Brown, T.F.; Sullivan, K.E., 1997: Varicella vaccination in patients with DiGeorge Syndrome. Journal of Allergy & Clinical Immunology 99(1 PART 2): S7

Al-Lawati, J.A.; Mabry, R.; Mohammed, A.Jaffer., 2008: Addressing the threat of chronic diseases in Oman. Introduction - The overall health status of the Omani population has evolved over the past 4 decades from one dominated by infectious disease to one in which chronic disease poses the main challenge. Along with a marked reduction in the incidence...

Jenssen, A.O., 1973: Measurement of resistance to air flow in the nose in a trial with sodium cromoglycate (BP)solution in allergen-induced nasal stenosis. Clinical Allergy 3(3): 277-282

Navas-Camacho, Rúl.; Gil-Agudelo, D.Luis.; Rodríguez-Ramírez, A.; Reyes-Nivia, Mía.Catalina.; Garzón-Ferreira, J., 2010: Coral diseases and bleaching on Colombian Caribbean coral reefs. Since 1998 the National Monitoring System for the Coral Reefs of Colombia (SIMAC) has monitored the occurrence of coral bleaching and diseases in some Colombian coral reefs (permanent stations at San Andres Island, Rosario Islands, Tayrona, San Be...