Journal of Clinical Psychology in Medical Settings, Vol. 11, No. 1, March 2004 ( C  2004) Nonadherence in Adolescent Oncology Patients: Preliminary Data on Psychological Risk Factors and Relationships to Outcome Beth D. Kennard, 1,2,3 Sunita M. Stewart, 1,2 Rebecca Olvera, 1,2 Roger E. Bawdon, 1 Ann O hAilin, 1 Charles P. Lewis, 1 and Naomi J. Winick 1,2 Published nonadherence rates in the adolescent oncology population range from 33 to 60% though little is known about the psychological factors that contribute to adherence and the relationship between outcome and nonadherence. Our study was designed to investigate psychological and family factors related to adherence and the relationship between adher- ence and survival in this population. We evaluated 44 (27 males, 17 females) patients with cancer (13–17 years) who were at least 6-months postdiagnosis. Adherence with trimetho- prim/sulfamethoxazole (TMP/SMX) was determined at one point in time, using serum assay. Twelve of the patients (27%) had no detectable TMP/SMX. Patients without detectable drug had higher levels of depression, lower self-esteem, and higher levels of parent–child incon- gruence. Survival rates, 6 years after the initiation of the study, were lower in the group of participants categorized as nonadherent. These findings, if confirmed, have implications for the management of nonadherence and mood in this population. KEY WORDS: nonadherence; adolescent; oncology; psychological factors; survival. Patient noncompliance or nonadherence with medical instructions is a behavior, which seriously affects the efficacy of prescribed medical treatments. Although it has drawn the attention of much re- search, compliance is a complex issue, which can differ greatly between groups of patients and between treatments of different medical conditions, and its study has often been confounded by disagreement about the nature of compliance. Compliance is often defined as the extent to which patient behavior coincides with prescribed medical advice (Kyng¨ as, Kroll, & Duffy, 2000; Litt & Cuskey, 1980; Partridge, Avorn, Wang, & Winer, 2002). Because the word “compliance” tends to connote acquiescence to coercion or submission 1 University of Texas Southwestern Medical Center of Dallas, Texas. 2 Children’s Medical Center of Dallas, Texas. 3 Correspondence should be addressed to Beth D. Kennard, Psy.D., 5323 Harry Hines Blvd., Division of Psychology, UT Southwestern Medical Center, Dallas, Texas 75390-9044; e-mail: beth.kennard@utsouthwestern.edu. to commands, the concept of “adherence” to med- ical regimens has in many cases replaced that of “compliance” as the preferred term for this behav- ior. “Adherence” emphasizes the patient’s active, intentional acceptance of the responsibilities of self-care and the patient’s cooperation with health care personnel rather than the simple obedience to dictatorial rules and regimens (Kroll, Barlow, & Shaw, 1999; Kyng¨ as et al., 2000). Despite the fact that the use of the term “compliance” is still quite common in literature and tends to encompass a broader range of related issues (Kyng¨ as et al., 2000), “adherence” and “nonadherence” shall be used here in accordance with the prevailing shift from the concept of compliance to that of adherence. Although nonadherence is an important health issue for adults with chronic illness, research suggests that it is an even greater issue in adolescent popu- lations (Kyng¨ as et al., 2000). Rates of nonadherence in adolescents with chronic medical problems are generally believed to be at around 50% (Cromer & Tarnowski, 1989; Dunbar, 1983). Nonadherence in 31 1068-9583/04/0300-0031/0 C  2004 Plenum Publishing Corporation