Relationship between hemoglobin (Hb) concentration and 5-yr all-cause mortality in community-dwelling disabled older women (Women's Health and Aging Study I, 1992–2000). The figure shows a graphical display of relative risk estimates for the mortality linked to specific Hb concentrations compared with the risk linked to Hb of 12 g/dL. The curve represents smoothed relative mortality hazards across Hb concentrations, and the bars indicate their 95% confidence intervals. Also indicated is the 13.9 g/dL Hb threshold at which the slope of mortality risk decline was no longer statistically significant (i.e., the 95% confidence interval for the slope of the tangent included 0). The y-axis was transformed so that, for example, the graphical display of an increase in risk of the magnitude of two (hazard ratio (HR) = 2) would be equivalent to that of a decrease in risk of the same magnitude (HR = 0.5) in terms of scale size. Risk estimates are adjusted for age, race, congestive heart failure, coronary heart disease, peripheral artery disease, stroke, pulmonary disease, cancer, estimated creatinine clearance, ankle–arm index, depression, body mass index, smoking status, education, disability performing basic activities of daily living, and number of domains with difficulty. (Chaves PHM, Xue Q-L, Guralnik JM, et al. What does constitute normal hemoglobin concentration in community-dwelling disable older women? J Am Geriatr Soc. 2004;52(11):1811–1816. Modified, reprinted with permission.) Source: Section G. Hematology, Hazzard's Geriatric Medicine and Gerontology, 6e Citation: Halter JB, Ouslander JG, Tinetti ME, Studenski S, High KP, Asthana S. Hazzard's Geriatric Medicine and Gerontology, 6e; 2009 Available at: http://accessmedicine.mhmedical.com/DownloadImage.aspx?image=/data/books/halt6/halt6_c102f001.gif&sec=41597416&BookID=371&ChapterSecID=41587720&imagename= Accessed: October 30, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved