Uncertainty in Illness: Theory Review, Application, and Extension.

U ncertainty is a common psychological reaction to the experience of cancer. It is defined as “the inability to determine the meaning of illness-related events” and accurately anticipate or predict health outcomes (Mishel, 1988, p. 225). Uncertainty may be present at any point in the cancer trajectory but is common at diagnosis, initiation of new treatments, and transitions of care, when patients must cope with unfamiliar, complex, and potentially threatening experiences. Uncertainty in patients with cancer is correlated with several negative physical and psychological consequences, including symptom severity and interference in daily life, fear, emotional distress, reduced resourcefulness, a sense of losing control, and diminished quality of life (Germino et al., 2013; Hsu, Lu, Tsou, & Lin, 2003; Kazer, Bailey, Sanda, Colberg, & Kelly, 2011; Kim, Lee, & Lee, 2012; Mishel et al., 2005, 2009). Consequently, oncology nurses must be able to recognize and facilitate management of uncertainty among patients during their care. The purpose of this article is to provide an overview of Mishel’s uncertainty in illness theory, summarize current literature in patients with cancer, and discuss extension of the theory to include uncertainty in partners of patients with cancer.