Online Exclusive Article

Significance of Nonphysical Predictors of Distress in Cancer Survivors

Rhonda L. Johnson

Carly Larson

Lora L. Black

Kimberly G. Doty

Lisa VanHoose

cancer, Distress Thermometer, emotional, psychosocial
CJON 2016, 20(5), E112-E117. DOI: 10.1188/16.CJON.E112-E117

Background: The Distress Thermometer (DT) is a well-validated tool that is frequently used in patients with cancer to screen for general distress and to generate referrals. However, a majority of the DT problem list items relate to physical concerns; this may lead to psychosocial issues being overshadowed.

Objectives: The purpose of the current study is to examine the endorsement rates for nonphysical items, as well as the relationship between these items and overall DT scores.

Methods: A multiple logistic regression analysis of the first-time distress rating scale of 1,209 patients from 2005–2009 was conducted to determine whether nonphysical items on the DT significantly contributed to a patient falling into one of two categories: at risk for distress or not at risk for distress.

Findings: This study provides evidence that emotional variables are particularly significant for patients who are at risk for distress and, consequently, should be prioritized for intervention when endorsed on the DT problem list.

Jump to a section

    The Patient Protection and Affordable Care Act emphasized integrated care (i.e., the move toward a more complete and comprehensive healthcare system [(Kodner & Spreeuwenberg, 2002)]) as a modality for improving quality and value in health care. Physicians, nurses, and other providers were called to prioritize interdisciplinary initiatives to improve patient-centered services and treatment outcomes. The co-occurrence of common psychological disorders, such as depression and anxiety, with serious medical conditions is known to significantly increase treatment costs and negatively affect health outcomes, whether these are preexisting or diagnosed during the course of the cancer trajectory (DiMatteo, Lepper, & Croghan, 2000). Assessing patients’ emotional states and well-being in addition to physical symptoms is important.

    In cancer care, the Distress Thermometer (DT) is widely used during medical treatment to detect emotional and psychological wellness. Although the DT is highly effective in assessing overall patient distress levels, and studies have identified the most endorsed problem list items (Clark, Rochon, Brethwaite, & Edmiston, 2011; Kendall, Glaze, Oakland, Hansen, & Parry, 2011), a limited empirical understanding exists regarding how item scoring differentiates areas of distress. This information is critical to the appropriate interpretation of DT results and the subsequent efficacy of supplementary care referrals, such as psychology, physical therapy, occupational therapy, and chaplaincy services. Nurses are often the first provider to see a patient’s completed DT and identify symptoms of distress, as well as deliver interventions (Coolbrandt et al., 2014). Consequently, nurses must not only review the DT but also triage all concerns and make referrals to other services.

    Background

    Cancer management has traditionally focused on the physical impact of cancer and its related treatments. However, efforts in patient-centered care have extended the focus to additional domains that have the potential to influence critical aspects of suffering associated with a cancer diagnosis. To that end, the evaluation of well-being has focused on assessment of distress as a construct to include physical and psychosocial survey variables. Distress holds particular interest because of physical and emotional adversities inherent to cancer diagnosis and treatment. High levels of distress among cancer survivors (defined as patients from the time of diagnosis until death [National Cancer Institute ([NCI], n.d.) have been associated with impairments in quality of life, treatment adherence, and satisfaction with care (Jacobsen et al., 2005). Distressed patients may also intensify stress on healthcare systems and providers by increasing the number of visits to general practitioners, walk-in clinics, and emergency departments (Bultz & Carlson, 2005; Carlson & Bultz, 2004). Despite research showing the importance of identifying and addressing distress in patients with cancer, one study found that only 40% of physicians felt that they were prepared to give enough time to distressed patients because of time constraints. However, in the same study, 90% of nurses surveyed reported that they were able to provide the time needed for distressed patients (Mitchell, Kaar, Coggan, & Herdman, 2008), pointing to the importance of nurses in managing cancer distress, as well as the need for interdisciplinary care.

    To address and monitor known detrimental influences of distress, the National Comprehensive Cancer Network ([NCCN], 2016) has implemented intervention guidelines that recommend administration of the DT to all patients with cancer. Multiple studies, such as a meta-analysis of 42 studies and 14,808 patients (Ma et al., 2014), have validated the DT as an accurate and reliable rapid screening instrument for distress in patients with cancer. However, psychometric evaluations of the DT have largely centered on the single-item rating on a 0–10 scale, with scores of 4 or greater indicating clinically significant levels of distress. A dearth of research exists related to the problem list portion of the DT that assists clinicians in determining distress etiologies and accurately prioritizing referrals for supplementary care. Although the NCCN (2016) defines distress as “a multifactorial unpleasant emotional experience of a psychological, . . . social, and/or spiritual nature that interferes with the ability to cope effectively with cancer, its physical symptoms, and its treatment,” 19 of 32 items on the DT problem list are related to physical symptoms and problems (p. 3). A DT item review indicated that nonphysical concerns of patients undergoing treatment for cancer were substantial sources of distress (VanHoose et al., 2014). A previous analysis of the 1,205 patients with cancer in this study revealed that worry (n = 188, 68%), sleep (n = 131, 48%), fears (n = 131, 48%), nervousness (n = 131, 48%), pain (n = 129, 47%), and financial problems (n = 107, 39%) were the most frequently endorsed problem list items by those in the at-risk group (VanHoose et al., 2014). In addition, those who were at risk for distress were more than five times more likely to report difficulties with worry. This suggests that the psychosocial and emotional concerns of patients are particularly salient in influencing patient perception of distress (VanHoose et al., 2014). The purpose of the current study is to more fully explore and provide an in-depth analysis of endorsement rates for psychosocial problem list items (i.e., the selection of psychosocial problem list items to indicate that the patient had a problem in that particular area within the past three weeks) in relation to overall DT scores.

    Methods

    Institutional review board approval was obtained prior to the start of the study. A retrospective chart review was conducted to examine the relationship between individual psychosocial problem list items (i.e., all items not listed under “physical issues” on the DT) and overall distress ratings on the DT. Surveys completed by patients aged 18 years or older who received services at the University of Kansas Cancer Center (KUCC) in Westwood from February 2005 to February 2009 were eligible for inclusion in this study. The electronic health record system Healthcare Enterprise Repository for Ontological Narration was used to obtain demographic information from medical records.

    Instrument

    The DT is a paper-and-pencil self-report screening tool used to generate referrals to appropriate healthcare professionals (e.g., clinical psychologist, dietitian, social worker) based on specific response items and a separate overall distress rating. The DT version used in this study was modified from version 1 (Roth et al., 1998) and consists of an overall distress rating accompanied by a figure of a thermometer used as a visual scale. This scale ranges from 0 (no distress) to 10 (extreme distress). Thirty-six individual problem list items of concern are grouped into five categories: practical, relationship, emotional, spiritual, and physical (Lynch, Goodhart, Saunders, & O’Connor, 2010; Roth et al., 1998).

    From 2005–2009, KUCC nurses administered DT tests to all patients receiving cancer treatments or monitoring within the first six months of diagnosis. Although several patients completed multiple DT tests, this study is limited to data gathered from the initial administration. Screening surveys were given to the patient by a clinic nurse in an outpatient center prior to seeing the physician. Copies of the survey were scanned into patient files, and the numeric scores and specific item responses were later retrieved and documented for the purposes of this study.

    Data Analysis

    KUCC is an NCI-designated cancer center where a wide range of cancer diagnoses are treated. In accordance with previous studies that validated an overall DT score of 4 as the threshold for at risk for distress (Jacobsen et al., 2005; Ma et al., 2014; Roth et al., 1998), participants were categorized into not-at-risk (rating of 0–3) and at-risk (rating of 4–10) distress groups. Descriptive analyses and endorsement ratings of individual problem list items were calculated separately for each group. In addition, a multiple logistic regression model was performed for all items, including nonphysical problems, to examine item-predicted distress variance.

    Results

    A total of 1,205 patients met the criteria for inclusion in this study (completed first-time distress screening from 2005–2009, aged 18 years or older, received services at KUCC). The age range of the patients was 18–93 years, with a mean age of 58.42 years (SD = 12.87). Additional characteristics of this sample are reported in Table 1.

    As reported by VanHoose et al. (2014), preliminary analyses were conducted to identify differences in demographic variables (e.g., age, gender, marital status, race, number of cancer diagnoses) between patients in the two risk categories. The mean age was found to be significantly lower for those at risk for distress (mean = 55.63 years, SD = 11.81) than for those in the not-at-risk category (mean = 59.24, SD = 13.07) (t [489.375] = –4.35, p < 0.001). Additional significant differences were found in the rates of marital statuses between the two categories of patients (c2 = 10.59, p = 0.03). Examination of the standardized residuals allowed for attribution of this difference to a lower percentage of widowed patients in the not-at-risk category (about 12.2% of low risk and 6.9% of at risk, standardized residual of at-risk widowed patients = –2).

    A multiple logistic regression model was created to predict risk status from the 17 DT psychosocial problem list items. Because of the VanHoose et al. (2014) findings, age and marital status were included as control variables. The results of the logistic regression model indicate that psychosocial problems alone account for 31%–46% of the variance in distress status. In addition, those patients in the at risk for distress group are significantly more likely to endorse problems with worry, financial concerns, nervousness, and depression. See Table 2 for logistic regression results.

    To address the impact of psychosocial response items above and beyond physical concerns, a stepwise logistic regression was conducted, in which 21 physical problems and 17 psychosocial problems were entered into the equation in two different steps. The model containing only the physical problems and control variables accounts for 21%–32% of the variance in at-risk or not-at-risk distress status. Including the psychosocial problems increased the model’s predictive value to 33%–50%.

    Discussion

    Emotional concerns account for much of the variability in distress above and beyond physical symptoms, pointing to the importance of screening and addressing psychosocial issues in cancer care. Results indicate that worry is the DT item most likely to predict that a patient is at risk for distress. Worry is understood as a compulsive sequence of images and thoughts that occur with negative emotion (Borkovec, Robinson, Pruzinsky, & DePree, 1983). This finding is particularly relevant because worry may be overlooked in clinical evaluations that are traditionally oriented toward screening for symptoms of depression (e.g., thoughts of despair, energy loss, withdrawal) and anxiety (e.g., thoughts of future threat, somatic tension, avoidance) (Craske et al., 2009). Patients may feel more personally comfortable endorsing worry on the DT instead of the other emotional domain items, like anxiety, fear, depression, nervousness, and sadness. This may be a coping mechanism for normalizing a fear reaction to cancer diagnosis and treatment. Financial stress was also found to be the strongest predictor of distress in the practical domain, which is consistent with findings of the 2006 USA Today/Kaiser Family Foundation/Harvard School of Public Health National Survey of Households Affected by Cancer. Of families with a cancer diagnosis in the previous five years, 25% of patients used all or most of their savings, 13% borrowed funds to pay bills, 10% were unable to pay for basic needs (e.g., housing, utilities, food), 7% required a second mortgage on their home, and 3% declared bankruptcy (Henry J. Kaiser Family Foundation & Harvard School of Public Health, 2006). Such findings are consistent with many past studies showing a relationship between worry and distress (Jacobsen et al., 2005; Ransom, Jacobsen, & Booth-Jones, 2006; Shim, Shin, Jeon, & Hahm, 2008). Results of this study also indicated that the mean age of those who were at risk for distress was significantly lower than that of those who were not. Younger patients may be more vulnerable to distress because of additional developmental stress (e.g., starting a family, completing education, postponing life goals). Young adults may also experience higher levels of distress because of less experience with serious illness than older populations (CancerCare.org, 2012). A study of psychological distress in adolescents and young adults found that 12% of the population experienced chronic distress for the first year following diagnosis, with an additional 15% reporting delayed distress; in addition, patients reported substantial unmet needs regarding information, psychological counseling, and practical support (Zebrack et al., 2014).

    Although physical problems do affect overall distress in patients with cancer, nonphysical and psychosocial issues may have a greater negative influence on distress and suffering. A study of DT test items (VanHoose et al., 2014) found that item responses from the physical domain of the instrument, such as sleep and mobility concerns, are also predictive of the at-risk-for-distress categorization. However, the current study suggests that psychosocial problems account for more variability in distress above and beyond, as well as independent of, physical concerns. This finding is consistent with an American Society of Clinical Oncology (ASCO) study that found that patients with moderate to severe levels of distress report worry, fatigue, and pain, whereas patients with low distress report physical problems like fatigue, insomnia, tingling, and dry skin (Chaing, 2015). Patients who experience concerns in both the physical and psychosocial domains may be particularly vulnerable to distress, and increased clinical awareness of the reciprocal physical/psychosocial relationship may better inform the interpretation and use of DT psychometric scores. In addition, understanding the impact of psychosocial distress may provide opportunities to improve patient quality of life, as well as efficacy of care within treatment systems, by informing the appropriate prioritization of supplementary care.

    Although the NCCN instructions for DT administration include follow-up discussion between patients and providers (i.e., physicians and nurses) guided by patient-endorsed items, little research is related to how assessment results influence patient care in clinical practice. Measuring distress is a relatively new paradigm in cancer care, and oncology nurses play a vital role as the first line of patient assistance for distress screening and management. The results of this study suggest that oncology nurses should consider providing additional and more in-depth assessment of distress for patients who endorse any item in the emotional domain, regardless of the overall DT score. The importance of screening, assessing, and treating emotional distress is also reflected in updated guidelines from ASCO that call for periodic anxiety and depression evaluations for all patients with cancer throughout care (Andersen et al., 2014).

    Limitations

    This study found lower rates of distress compared to past studies. The timing of the DT administration may have affected the distress ratings in this study; some studies with higher distress ratings had DT administration at later time points in treatment (Ransom et al., 2006; Roth et al., 1998). In addition, the patients in this sample were mostly married Caucasian women; consequently, the findings may not generalize to populations at other institutions. However, this sample was representative of the larger KUCC patient population. The database used for this study did not include data about referrals for supplemental care, so ascertaining the rates at which at-risk patients were referred for psychosocial or other services is not possible. Future research would benefit from this information to better understand the practice of using distress screening to generate referrals to other professions. In addition, future studies may benefit from investigating distress in specific patient populations, such as those being treated with chemotherapy, to better understand emotional and physical well-being in clinically relevant subpopulations.

    Conclusion

    The DT is well validated in predicting clinical levels of general distress in cancer survivors. However, accurately identifying distress etiology is critical for informing efficacious treatment. Understanding the relationship between specific problem areas and their effect on distress may improve the interpretation and use of this psychometric assessment. This study suggests that psychosocial problems are particularly salient for patients who are experiencing distress and, therefore, should be prioritized for intervention when endorsed on the DT problem list. In addition, emotional concerns, such as fear and worry, appear to be key contributors to being at risk for distress (i.e., DT score of 4 or greater).

    Broadening the focus of cancer treatment to include assistance with psychosocial concerns has the potential to alleviate distress, increase patient quality of life and treatment adherence, and decrease system stress. The DT is designed to screen for areas of distress that may be overlooked in traditional clinical interactions. Assessment results can serve as an entry point for conversation, additional assessment, and resource referral. The findings of this study may assist providers in prioritizing supplementary care referrals toward resources that address emotional concerns.

    References

    Andersen, B.L., DeRubeis, R.J., Berman, B.S., Gruman, J., Champion, V.L., Massie, M.J., . . . Rowland, J.H. (2014). Screening, assessment, and care of anxiety and depressive symptoms in adults with cancer: An American Society of Clinical Oncology guideline adaptation. Journal of Clinical Oncology, 32, 1605–1619. doi:10.1200/JCO.2013.52.4611

    Borkovec, T.D., Robinson, E., Pruzinsky, T., & DePree, J.A. (1983). Preliminary explanation of worry: Some characteristics and processes. Behaviour Research and Therapy, 21, 9–16.

    Bultz, B.D., & Carlson, L.E. (2005). Emotional distress: The sixth vital sign in cancer care. Journal of Clinical Oncology, 23, 6440–6441. doi:10.1002/pon.1022

    CancerCare.org. (2012). Coping with cancer as a young adult. Retrieved from https://media.cancercare.org/publications/original/164-ccc_young_adult_…

    Carlson, L.E., & Bultz, B.D. (2004). Efficacy and medical cost offset of psychosocial interventions in cancer care: Making the case for economic analyses. Psycho-Oncology, 13, 837–849. doi:10.1002/pon.832 

    Chaing, A. (2015, May 30). Accessing emotional distress in patients with cancer. Retrieved from http://am.asco.org/assessing-emotional-distress-patients-cancer

    Clark, P.G., Rochon, E., Brethwaite, D., & Edmiston, K.K. (2011). Screening for psychological and physical distress in a cancer inpatient treatment setting: A pilot study. Psycho-Oncology, 20, 664–668. doi:10.1002/pon.1908

    Coolbrandt, A., Wildiers, H., Aertgeerts, B., Van der Elst, E., Laenen, A., Dierckx de Casterlé, B., . . . Milisen, K. (2014). Characteristics and effectiveness of complex nursing interventions aimed at reducing symptom burden in adult patients treated with chemotherapy: A systematic review of randomized controlled trials. International Journal of Nursing Studies, 51, 495–510. doi:10.1016/j.ijnurstu.2013.08.008

    Craske, M.G., Rauch, S.L., Ursano, R., Prenoveau, J., Pine, D.S., & Zinbarg, R.E. (2009). What is an anxiety disorder? Depression and Anxiety, 26, 1066–1085. doi:10.1002/da.20633

    DiMatteo, M.R., Lepper, H.S., & Croghan, T.W. (2000). Depression is a risk factor for noncompliance with medical treatment: Meta-analysis of the effects of anxiety and depression on patient adherence. Archives of Internal Medicine, 160, 2101–2107. doi:10.1001/archinte.160.14.2101

    Henry J. Kaiser Family Foundation & Harvard School of Public Health. (2006, November). The USA Today/Kaiser Family Foundation/Harvard School of Public Health National Survey of Households Affected by Cancer. Retrieved from https://kaiserfamilyfoundation.files.wordpress.com/2013/01/7591.pdf

    Jacobsen, P.B., Donovan, K.A., Trask, P.C., Fleishman, S.B., Zabora, J., Baker, F., & Holland, J.C. (2005). Screening for psychologic distress in ambulatory cancer patients: A multicenter evaluation of the Distress Thermometer. Cancer, 103, 1494–1502. doi:10.1002/cncr.20940

    Kendall, J., Glaze, K., Oakland, S., Hansen, J., & Parry, C. (2011). What do 1281 distress screeners tell us about cancer patients in a community cancer center? Psycho-Oncology, 20, 594–600. doi:10.1002/pon.1907

    Kodner, D.L., & Spreeuwenberg, C. (2002). Integrated care: Meaning, logic, applications, and implications—A discussion paper. International Journal of Integrated Care, 2, e12.

    Lynch, J., Goodhart, F., Saunders, Y., & O’Connor, S.J. (2010). Screening for psychological distress in patients with lung cancer: Results of a clinical audit evaluating the use of the patient Distress Thermometer. Supportive Care in Cancer, 19, 193–202. doi:10.1007/s00520-009-0799-8

    Ma, X., Zhang, J., Zhong, W., Shu, C., Wang, F., Wen, J., . . . Liu, L. (2014). The diagnostic role of a short screening tool—The Distress Thermometer: A meta-analysis. Supportive Care in Cancer, 22, 1741–1755. doi:10.1007/s00520-014-2143-1

    Mitchell, A.J., Kaar, S., Coggan, C., & Herdman, J. (2008). Acceptability of common screening methods used to detect distress and related mood disorders—Preferences of cancer specialists and non‐specialists. Psycho‐Oncology, 17, 226–236. doi:10.1002/pon.1228

    National Cancer Institute. (n.d.). NCI dictionary of cancer terms. Survivor. Retrieved from http://www.cancer.gov/publications/dictionaries/cancer-terms?cdrid=4501…

    National Comprehensive Cancer Network. (2016). NCCN clinical practice guidelines in oncology (NCCN Guidelines®): Distress management [v.2.2016]. Retrieved from http://www.nccn.org/professionals/physician_gls/PDF/distress.pdf

    Ransom, S., Jacobsen, P.B., & Booth-Jones, M. (2006). Validation of the Distress Thermometer with bone marrow transplant patients. Psycho-Oncology, 15, 604–612. doi:10.1002/pon.993

    Roth, A.J., Kornblith, A.B., Batel-Copel, L., Peabody, E., Scher, H.I., & Holland, J.C. (1998). Rapid screening for psychologic distress in men with prostate carcinoma. Cancer, 82, 1904–1908. doi:10.1002/(SICI)1097-0142(19980515)82:10<1904::AID-CNCR13>3.0.CO;2-X

    Shim, E.J., Shin, Y.W., Jeon, H.J., & Hahm, B.J. (2008). Distress and its correlates in Korean cancer patients: Pilot use of the Distress Thermometer and the problem list. Psycho‐Oncology, 17, 548–555. doi:10.1002/pon.1275

    VanHoose, L., Black, L.L., Doty, K., Sabata, D., Twumasi-Ankrah, P., Taylor, S., & Johnson, R. (2014). An analysis of the Distress Thermometer problem list and distress in patients with cancer. Supportive Care in Cancer, 23, 1225–1232. doi:10.1007/s00520-014-2471-1

    Zebrack, B.J., Corbett, V., Embry, L., Aguilar, C., Meeske, K.A., Hayes-Lattin, B., . . . Cole, S. (2014). Psychological distress and unsatified need for psychosocial support in adolescent and young adult cancer patients during the first year following diagnosis. Psycho-Oncology, 23, 1267–1275. doi:10.1002/pon.3533

    About the Author(s)

    Rhonda L. Johnson, PhD, is the director of patient support services at Saint Luke’s Cancer Institute in Kansas City, MO; Carly Larson, BA, is a PhD student in the Department of Clinical Psychology at Fielding Graduate University in Santa Barbara, CA; Lora L. Black, PhD, MPH, is a postdoctoral researcher at the Ohio State University Wexner Medical Center in Columbus; Kimberly G. Doty, MS, is the principal consultant at Datatistics LLC in Kansas City; and Lisa VanHoose, PhD, MPH, PT, is an assistant professor in the Department of Physical Therapy at the University of Central Arkansas in Little Rock. The authors take full responsibility for the content of the article. The study was supported, in part, by an award (K12HD052027) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health. The content of this article has been reviewed by independent peer reviewers to ensure that it is balanced, objective, and free from commercial bias. No financial relationships relevant to the content of this article have been disclosed by the independent peer reviewers or editorial staff. Johnson can be reached at rhojohnson@saint-lukes.org, with copy to editor at CJONEditor@ons.org. (Submitted August 2015. Revision submitted December 2015. Accepted for publication December 18, 2015.)

     

    References

    Andersen, B.L., DeRubeis, R.J., Berman, B.S., Gruman, J., Champion, V.L., Massie, M.J., . . . Rowland, J.H. (2014). Screening, assessment, and care of anxiety and depressive symptoms in adults with cancer: An American Society of Clinical Oncology guideline adaptation. Journal of Clinical Oncology, 32, 1605–1619. doi:10.1200/JCO.2013.52.4611
    Borkovec, T.D., Robinson, E., Pruzinsky, T., & DePree, J.A. (1983). Preliminary explanation of worry: Some characteristics and processes. Behaviour Research and Therapy, 21, 9–16.
    Bultz, B.D., & Carlson, L.E. (2005). Emotional distress: The sixth vital sign in cancer care. Journal of Clinical Oncology, 23, 6440–6441. doi:10.1002/pon.1022
    CancerCare.org. (2012). Coping with cancer as a young adult. Retrieved from https://media.cancercare.org/publications/original/164-ccc_young_adult_…
    Carlson, L.E., & Bultz, B.D. (2004). Efficacy and medical cost offset of psychosocial interventions in cancer care: Making the case for economic analyses. Psycho-Oncology, 13, 837–849. doi:10.1002/pon.832 
    Chaing, A. (2015, May 30). Accessing emotional distress in patients with cancer. Retrieved from http://am.asco.org/assessing-emotional-distress-patients-cancer
    Clark, P.G., Rochon, E., Brethwaite, D., & Edmiston, K.K. (2011). Screening for psychological and physical distress in a cancer inpatient treatment setting: A pilot study. Psycho-Oncology, 20, 664–668. doi:10.1002/pon.1908
    Coolbrandt, A., Wildiers, H., Aertgeerts, B., Van der Elst, E., Laenen, A., Dierckx de Casterlé, B., . . . Milisen, K. (2014). Characteristics and effectiveness of complex nursing interventions aimed at reducing symptom burden in adult patients treated with chemotherapy: A systematic review of randomized controlled trials. International Journal of Nursing Studies, 51, 495–510. doi:10.1016/j.ijnurstu.2013.08.008
    Craske, M.G., Rauch, S.L., Ursano, R., Prenoveau, J., Pine, D.S., & Zinbarg, R.E. (2009). What is an anxiety disorder? Depression and Anxiety, 26, 1066–1085. doi:10.1002/da.20633
    DiMatteo, M.R., Lepper, H.S., & Croghan, T.W. (2000). Depression is a risk factor for noncompliance with medical treatment: Meta-analysis of the effects of anxiety and depression on patient adherence. Archives of Internal Medicine, 160, 2101–2107. doi:10.1001/archinte.160.14.2101
    Henry J. Kaiser Family Foundation & Harvard School of Public Health. (2006, November). The USA Today/Kaiser Family Foundation/Harvard School of Public Health National Survey of Households Affected by Cancer. Retrieved from https://kaiserfamilyfoundation.files.wordpress.com/2013/01/7591.pdf
    Jacobsen, P.B., Donovan, K.A., Trask, P.C., Fleishman, S.B., Zabora, J., Baker, F., & Holland, J.C. (2005). Screening for psychologic distress in ambulatory cancer patients: A multicenter evaluation of the Distress Thermometer. Cancer, 103, 1494–1502. doi:10.1002/cncr.20940
    Kendall, J., Glaze, K., Oakland, S., Hansen, J., & Parry, C. (2011). What do 1281 distress screeners tell us about cancer patients in a community cancer center? Psycho-Oncology, 20, 594–600. doi:10.1002/pon.1907
    Kodner, D.L., & Spreeuwenberg, C. (2002). Integrated care: Meaning, logic, applications, and implications—A discussion paper. International Journal of Integrated Care, 2, e12.
    Lynch, J., Goodhart, F., Saunders, Y., & O’Connor, S.J. (2010). Screening for psychological distress in patients with lung cancer: Results of a clinical audit evaluating the use of the patient Distress Thermometer. Supportive Care in Cancer, 19, 193–202. doi:10.1007/s00520-009-0799-8
    Ma, X., Zhang, J., Zhong, W., Shu, C., Wang, F., Wen, J., . . . Liu, L. (2014). The diagnostic role of a short screening tool—The Distress Thermometer: A meta-analysis. Supportive Care in Cancer, 22, 1741–1755. doi:10.1007/s00520-014-2143-1
    Mitchell, A.J., Kaar, S., Coggan, C., & Herdman, J. (2008). Acceptability of common screening methods used to detect distress and related mood disorders—Preferences of cancer specialists and non‐specialists. Psycho‐Oncology, 17, 226–236. doi:10.1002/pon.1228
    National Cancer Institute. (n.d.). NCI dictionary of cancer terms. Survivor. Retrieved from http://www.cancer.gov/publications/dictionaries/cancer-terms?cdrid=4501…
    National Comprehensive Cancer Network. (2016). NCCN clinical practice guidelines in oncology (NCCN Guidelines®): Distress management [v.2.2016]. Retrieved from http://www.nccn.org/professionals/physician_gls/PDF/distress.pdf
    Ransom, S., Jacobsen, P.B., & Booth-Jones, M. (2006). Validation of the Distress Thermometer with bone marrow transplant patients. Psycho-Oncology, 15, 604–612. doi:10.1002/pon.993
    Roth, A.J., Kornblith, A.B., Batel-Copel, L., Peabody, E., Scher, H.I., & Holland, J.C. (1998). Rapid screening for psychologic distress in men with prostate carcinoma. Cancer, 82, 1904–1908. doi:10.1002/(SICI)1097-0142(19980515)82:10<1904::AID-CNCR13>3.0.CO;2-X
    Shim, E.J., Shin, Y.W., Jeon, H.J., & Hahm, B.J. (2008). Distress and its correlates in Korean cancer patients: Pilot use of the Distress Thermometer and the problem list. Psycho‐Oncology, 17, 548–555. doi:10.1002/pon.1275
    VanHoose, L., Black, L.L., Doty, K., Sabata, D., Twumasi-Ankrah, P., Taylor, S., & Johnson, R. (2014). An analysis of the Distress Thermometer problem list and distress in patients with cancer. Supportive Care in Cancer, 23, 1225–1232. doi:10.1007/s00520-014-2471-1
    Zebrack, B.J., Corbett, V., Embry, L., Aguilar, C., Meeske, K.A., Hayes-Lattin, B., . . . Cole, S. (2014). Psychological distress and unsatified need for psychosocial support in adolescent and young adult cancer patients during the first year following diagnosis. Psycho-Oncology, 23, 1267–1275. doi:10.1002/pon.3533