JOURNAL OF PALLIATIVE MEDICINE Volume 14, Number 3, 2011 ª Mary Ann Liebert, Inc. DOI: 10.1089/jpm.2010.0412 Measuring Symptom Distress in Palliative Care: Psychometric Properties of the Symptom Assessment Scale (SAS) Samar M. Aoun, B.Sc.(Hons), M.P.H., Ph.D.,1 Leanne Monterosso, BNurs(Hons), Ph.D.,2 Linda J. Kristjanson, B.N., M.N., Ph.D.,1 and Ruth McConigley, B.Sc., MNurs, Ph.D.3 Abstract Given the variety of palliative care settings within which symptom distress must be assessed, development of a valid and reliable clinical tool that can be simply applied in every day practice is needed. The Symptom Assessment Scale (SAS) uses a 0–10 numerical scale with zero being no symptom and 10 being the worst possible. The key symptoms included in the scale are breathing, bowel problems, appetite problems, pain, insomnia, nausea and fatigue. The instrument is structured to allow either the patient, family member or nurse to assess the symptoms. The scale was tested on 572 cancer patients recruited from five palliative care services in Western Australia. Results indicated that the instrument was brief, clinically useful and was administered with minimal missing data. Internal consistency reliability estimates of the scale ranged from 0.64–0.92 as measured by the Cronbach’s alpha coefficient. Test-retest reliabilities of 0.84–0.92 were obtained using Pearson’s correlation co-efficient. The instrument does not provide an in-depth assessment of individual symptoms, but serves as a screening tool to identify troublesome symptoms that warrant attentive and immediate investigation and comprehensive assessment. Introduction atients living with cancer and other life-limiting illnesses may experience myriad complex symptoms, such as pain, nausea, breathlessness, and insomnia, requiring monitoring and management. Assessing and monitoring changes in a patient’s symptoms can pose considerable difficulties for clinicians. However, it is widely accepted that impeccable symptom assessment is required if good symptom management is to be achieved.1 In response to this concern, a number of palliative care–specific assessment tools have been developed, including a number of patient self-report rating scales for symptom assessment, most of which report sound psychometric properties.2–4 Although the empirical literature describes the use of these instruments for research purposes, less has been written about the extent to which these tools have been adopted for use in clinical practice. The purpose of this article is to describe the development and testing of one such tool suitable for both clinical and research purposes, the Symptom Assessment Scale (SAS). The most commonly used of such instruments is the Edmonton Symptom Assessment Scale (ESAS), which has been P used extensively in clinical and research settings. Two recent reviews showed that the ESAS is a reliable symptom assessment tool, although there is a need for further validity testing to support use of the ESAS in a variety of settings.5,6 Chang and colleagues7 also noted that some patients found it difficult to understand and complete the visual analogue scales of the ESAS. A more recent study on the routine use of the ESAS8 reported challenges such as lack of clarity about frequency of assessments and difficulty interpreting the symptom rating scale. The Memorial Symptom Assessment Scale (MSAS) is a patient-rated instrument that captures patient-rated severity, frequency, and distress associated with 32 highly prevalent physical and psychological symptoms. In its complete form it can be time consuming to complete.9 Other instruments are also described in the literature. The Support Team Assessment Schedule (STAS) consists of 17 items that are used to evaluate a wide range of patient, family, and service issues.3 With the exception of pain and anxiety, all other symptoms are aggregated under one item labelled ‘‘symptom control.’’ This limits the sensitivity of the tool in terms of identifying and measuring distress caused by a specific symptom and the evaluation of interventions targeted 1 Western Australian Centre for Cancer and Palliative Care, Curtin Health Innovation Research Institute, Curtin University, Perth, Western Australia, Australia 2 School of Nursing, The University of Notre Dame Australia, Fremantle, Australia. 3 School of Nursing and Midwifery, Curtin University, Perth, Western Australia, Australia. Accepted October 14, 2010. 315 316 at that symptom. Hearn and Higginson10 developed the Palliative Care Outcome Scale (POS), which assesses physical symptoms (pain and other symptoms together) and psychological, spiritual, and practical domains. However, the authors concede that future development of POS should incorporate more symptom information, notably about nausea, weakness, and breathlessness. The Symptom Distress Scale (SDS) was developed by McCorkle and Young11 to assess subjective experiences of distress. The SDS examines the distress caused by 10 common symptoms, measured on a scale of 1 to 5, with ‘‘1’’ indicating little or no distress and ‘‘5’’ indicating great distress. The instrument was tested with a group of cancer patients and a group of individuals who had experienced a myocardial infarction. The tool demonstrated acceptable reliability and validity estimates and was found to be brief and relatively simple to administer. Since then the tool has undergone minor revisions and has been tested with patients with cancer in a variety of settings.12–18 This instrument continues to be used for measuring symptoms in research settings,19–21 but there are less data about its usefulness as a clinical tool. An adapted version, the Adapted Symptom Distress Scale-2, has also been used in the research setting.22,23 The development of the Symptom Assessment Scale (SAS) Kristjanson and colleagues24 undertook a multisite study to pilot test the SDS with the primary aim of determining the extent that the tool would be appropriate for application in the Australian cancer care context. Results from this pilot work suggested the tool was useful; however, some changes were required to simplify the instrument and also adapt it to make it more culturally appropriate to the Australian population. Modifications included the removal of items related to mobility, mood, concentration, and appearance. One item relating to breathing problems was added. The revised instrument was labelled the Symptom Assessment Scale (SAS) (see the Appendix). It comprises the following seven items: pain, insomnia, nausea, bowel problems, appetite problems, breathing problems, and fatigue. Patients rate the degree of distress associated with the symptom using a 0 to 10 Likert-type verbal rating scale with zero being no symptom distress experienced, ‘‘1’’ being minimal symptom distress, and ‘‘10’’ being the worst possible symptom distress. The time frame for rating the symptoms is in the past 24 hours. Clinicians can add other symptoms experienced by each patient as appropriate. The instrument is structured to allow either the patient, family member, or nurse to assess the symptoms. Although frequent assessment of physical symptoms is a necessary and routine practice, the suitability of frequent assessment of psychological well-being of patients was pretested and found in the pilot study to be intrusive. Patients indicated that they were willing to provide information about physical symptoms (e.g., pain, nausea) because something could be offered to assist with these symptoms. However, to inquire about their feelings such as depression on a daily basis was inappropriate and upsetting. Advice provided indicated that this type of question might be better addressed in a different way, allowing more time for discussion about feelings with a staff member with whom they had a closer relationship. This finding may reflect cultural perspectives AOUN ET AL. with respect to the context within which discussions of psychological issues occurs. A survey of symptom assessment tools used in Australian services found that 28% of services used the SAS compared with 14% that used the ESAS and 2% that used the MSAS (the rest using unvalidated tools), and both ESAS and MSAS include questions related to psychological distress.25 This article reports the reliability and validity testing of the SAS, a short patient-rated scale of symptom distress that is widely used in Australian clinical palliative care settings both as a clinical tool and for monitoring the quality of care provision.26–28 Although the SAS was developed in 1999 and extensive testing of the instrument was undertaken at that time, the results of the testing were never published in a peerreviewed publication. This article reports the findings from the original testing procedures that were completed in 1999 and analysed further in 2009 and provides information regarding the ongoing use and testing of the SAS in subsequent studies. Testing of the SAS The following questions were addressed: 1. To what extent does the SAS demonstrate internal consistency reliability? 2. To what extent does the SAS demonstrate stability over time? 3. To what extent does the SAS demonstrate construct validity? 4. To what extent does the SAS demonstrate sensitivity to changes in patient’s condition over time? Approval to conduct this study was obtained from the human research ethics committees of Edith Cowan University and each study setting. The study was undertaken between January and December 1998 and documented in a report in 1999.24 Methods Sample and setting A consecutive sampling of mainly cancer patients receiving palliative care in five services in Perth, Western Australia over a 12-month period was obtained. These services were all major services existing at the time of the study. This population was selected because of the high incidence of symptom distress associated with palliative care. Hence, the sample was able to provide useful data regarding the consistency, stability over time, and construct validity of the instrument. Participants were recruited from five palliative care services covering three different settings: consultative palliative care services (n ¼ 2), inpatient palliative care units (n ¼ 2) and home care service (n ¼ 1). The inpatient units had a combined total of 48 beds, with an occupancy rate of approximately 90%. The home care service provided palliative care to patients throughout the metropolitan area of Perth, both in the home and in residential aged care settings, with an ongoing caseload of approximately 400 patients. The two consultative palliative care services received approximately 12 new referrals per week. Symptom assessment was performed daily for each patient by the bedside nurse and recorded on a Symptom Assessment Recording Form. Training was undertaken to ensure MEASURING SYMPTOM DISTRESS IN PALLIATIVE CARE consistency in administering the tool. Patients were asked to assess the degree of distress they were experiencing with respect to seven symptoms of the SAS. Patients indicated verbally, or by pointing to the number on the scale, the level of severity of symptom distress. SAS scores were reported for each patient on at least five occasions, allowing for testing of sensitivity of the SAS to changes in symptoms over time. Statistical analyses Descriptive statistics were used to describe the sample in terms of demographic characteristics, clinical characteristics, and symptom distress variability. Internal consistency reliability was assessed using Cronbach’s standardized a coefficient. A criterion of at least 0.70 was preset as the minimum for internal consistency, which is considered acceptable for a newly developed instrument.29 As well, Carmines and Zeller30 suggested that 50% of item-tototal correlation should be between 0.40 and 0.70. Scores above 0.70 indicate redundancy of items, and scores below 0.40 indicate that the item may not contribute information about needs parallel with other scale items. The intraclass correlation coefficient was used to determine stability of the SAS over time. This statistic allowed for an assessment of the extent of agreement across the two time points while correcting for possible chance agreement. A correlation of at least 0.70 was preset as the criterion for satisfactory test-retest reliability.29 Construct validity was evaluated using the ‘‘known group validity’’ technique and was assessed by comparing symptom assessment scores of patients with different cancer diagnoses. An analysis of variance (ANOVA) was used to test for differences in the Time 1 (T1) scores with a Sheffe post hoc test used to test for statistical differences between the groups, based on comparisons of scores across cancer diagnoses known or hypothesized to score differently. We hypothesized that the SAS would be able to discriminate individual symptom distress scores between patients with different cancer diagnoses. For example, we hypothesized that patients with lung and head and neck cancers would have higher distress scores for breathing than patients with other cancer diagnoses. Likewise, patients with breast cancer would have higher pain scores than patients with other cancers. A repeated measures general linear model was used to determine the sensitivity of the SAS to changes in symptom scores over five time points. This was an important requirement to determine whether the SAS was a useful tool that could be used in the clinical setting to detect expected changes in a patient’s condition over time. For example, it was hypothesized that distress related to pain would decrease over time as the palliative care team implemented effective symptom management of this problem. Results Sample characteristics We recruited 572 patients from five different palliative care specialist services in Western Australia. Data from 18 recruited participants were not included in the analysis for the following reasons: patient was deceased prior to data collection (n ¼ 8), no submission of data (n ¼ 7), patient was diagnosed as terminal after recruitment (n ¼ 1), patient was 317 discharged prior to data collection (n ¼ 1), or the patient decided not to participate (n ¼ 1). (See Table 1.) Clinical characteristics A wide range of cancer diagnoses were included in the sample; most patients had metastatic disease and had undergone some form of cancer treatment, and 22% continued to have active treatment. Only 5% of patients had a diagnosis of nonmalignant disease. (See Table 2.) Instrument Testing Symptom intensity. (See Table 3.) The possible SAS score range for each symptom was 0 to10 (0 ¼ no problems to 10 ¼ worst possible problem). The range of mean SAS scores was 2.30 (nausea) to 5.83 (fatigue). Internal consistency. The SAS achieved an internal consistency estimate as measured by Cronbach’s a of 0.62 ( p < 0.001) using T1 SAS scores. This estimate was just below the preset criterion of 0.70 and indicated a moderate degree of internal consistency. The total score on the SAS was also correlated with each symptom score. All seven symptoms (100%) achieved item-to-total correlations between 0.40 and 0.70. This was well above the preset range of at least 50% of items within this range. Construct validity. (See Table 4.) As hypothesized, patients with breast cancer had the highest scores for appetite problems, nausea, bowel problems, and pain of any cancer group. Patients diagnosed with lung cancer had higher breathing scores than other cancer groups. Post hoc tests showed patients with head and neck and lung cancers had significantly higher breathing scores than patients diagnosed with colon cancer ( p ¼ 0.005), leukemia ( p ¼ 0.001), Table 1. Demographic Profile of Patients (n ¼ 572) Gender Male Female Age 25–60 61–70 71–80 81–98 Marital Status Married/de facto Never married Divorced/separated Widowed Country of birth Australia UK Other Preferred language English Other Palliative care service type Consultative service Home care service Inpatient unit n (%) 333 (58) 237 (42) 117 112 220 119 (21) (20) (39) (21) 324 48 44 142 (58) (9) (8) (25) 349 (63) 114 (21) 91 (16) 526 (92) 46 (8) 91 (16) 196 (34) 285 (50) AOUN ET AL. Symptom Appetite Bowel Breathing Fatigue Insomnia Nausea Pain n Mean SD 544 542 545 539 544 548 540 4.72 3.80 3.14 5.83 3.48 2.30 3.98 3.166 3.139 3.191 2.772 2.914 2.826 3.054 SD, standard deviation. Other 6.16 (2.76) Colon 5.73 (2.51) Prostate 5.72 (2.77) Gastric 5.67 (2.62) Breast 5.65 (2.97) Head/neck 5.54 (2.81) Lung 5.46 (3.05) Fatigue Breathing Lung 4.54 (3.38) Head/neck 3.27 (3.21) Breast 2.93 (3.09) Colon 2.49 (3.00) Gastric 2.46 (2.96) Other 2.35 (2.86) Prostate 2.31 (2.86) SD, standard deviation. Table 3. Mean SAS Scores for Each Symptom Breast 4.89 (3.30) Prostate 4.47 (3.2) Other 4.12 (3.24) Gastric 3.52 (3.23) Lung 3.48 (2.96) Colon 3.09 (3.02) Head/neck 2.72 (2.65) and prostate cancer ( p ¼ 0.008). Patients with gastric cancer had significantly lower pain scores than patients diagnosed breast cancer ( p ¼ 0.029). There were significant differences between cancer diagnosis and bowel symptom scores (F ¼ 2.334, p ¼ 0.018), breathing symptoms scores (F ¼ 7.540, p < 0.001) and pain (F ¼ 4.326, p < 0.001). Post hoc tests show patients without cancer had significantly higher breathing scores than patients diagnosed with colon ( p ¼ 0.006), gastric ( p ¼ 0.019), genitourinary ( p ¼ 0.006), and other cancers ( p ¼ 0.006). Patients with lung cancer had significantly higher breathing scores than patients diagnosed with colon cancer ( p ¼ 0.005), leukemia ( p ¼ 0.001), and genitourinary cancer ( p ¼ 0.008). Patients with gastric cancer had significantly lower pain Breast 2.90 (3.12) Other 2.55 (2.79) Colon 2.4 (2.80) Gastric 2.3 (2.99) Prostate 2.07 (2.70) Lung 1.79 (2.65) Head/neck 1.72 (1.90) (9) (16) (3) (5) (17) (34) Breast 5.16 (3.08) Head/neck 4.76 (3.44) Other 4.74 (3.27) Colon 4.69 (3.27) Lung 4.66 (3.04) Prostate 4.34 (3.08) Gastric 4.28 (3.08) 49 91 17 26 96 196 Bowel 44 (8) 67 (12) 13 (2) Nausea 175 (31) 225 (40) 248 (44) Appetite (29) (8) (20) (13) (25) Insomnia 162 43 112 73 141 Pain n (%) 41 (7) 92 (16) 46 (8) 26 (5) 121 (21) 62 (11) 149 (26) 29 (5) 33.3 Table 4. Mean SAS Scores Ranked by Cancer Diagnosis (SD) Primary diagnosis Breast Colon Gastric Head/neck Lung Prostate Other Not cancer Average time since diagnosis (months) Secondary involvement Bone Brain Liver Lung Other Previous treatment Chemotherapy Radiotherapy Surgical Current treatment Chemotherapy Radiotherapy Surgical Comorbidity Arthritis Chronic lung disease Cognitive impairment Neurological conditions Symptomatic heart disease Other Prostate 3.67 (2.99) Other 3.65 (2.95) Colon 3.56 (3.07) Lung 3.50 (2.94) Head/neck 3.44 (2.62) Breast 3.08 (3.02) Gastric 2.80 (2.73) Table 2. Clinical Profile of Patients (n ¼ 572) Breast 5.03 (2.94) Head/neck 4.92 (2.73) Prostate 4.44 (2.92) Lung 4.03 (3.14) Colon 3.71 (2.88) Other 3.41 (3.01) Gastric 2.33 (2.46) 318 MEASURING SYMPTOM DISTRESS IN PALLIATIVE CARE scores than patients diagnosed with breast cancer ( p ¼ 0.029). 319 Table 6. Sensitivity of SAS Over Time F sig 3.811 2.092 2.205 1.155 3.833 5.090 10.252 0.005 0.084 0.070 0.332 0.005 0.001 <0.001 Stability over time. (See Table 5.) A subsample of patients participated in the test-retest reliability assessment (n ¼ 60). Participants completed the SAS at T1 and 2 hours later at time two (T2). This time frame was chosen to minimize variations in symptom distress over time, allowing testing of the reliability of the instrument. Research staff also confirmed that no pain medication or symptom intervention was administered during this time interval. Results indicated a significant level of agreement among participants ranging from r ¼ 0.84 for nausea and breathing to r ¼ 0.94 for pain. Symptom Appetite Bowel Breathing Fatigue Insomnia Nausea Pain Sensitivity to change over time. (See Table 6.) Repeated measures over five time points demonstrated the SAS is sensitive to changes in symptom distress over time as shown in the symptoms of appetite, insomnia, nausea, and pain. Bowel symptoms, breathing, and fatigue scores did not change significantly over time. The average time between symptom assessments was 2.35 days, ranging from 1.4 to 17.1 days. specific to the cancer type. Our construct validity using known group comparisons demonstrated differences in symptom distress scores among different cancer diagnostic groups. This study also provided information about the incidence and intensity of symptom distress in people with advanced cancer in a variety of inpatient and outpatient settings. With respect to appetite, breathing, bowel, fatigue, insomnia, nausea, and pain symptoms assessed in this study, the most striking finding is that participants experienced multiple symptoms. This is expected given that people with advanced cancer may have a number of coexisting morbidities and metastatic disease. Overall, symptoms were more prevalent in the diagnostic groups of lung and bowel cancer. Family members and nurses can be included as SAS assessors to avoid exclusion of the group of patients who may be unable to respond themselves and yet are perhaps those that may benefit most from measuring levels of symptom distress. The role of caregivers, particularly in home care, and the need for them to be educated regarding symptom distress is acknowledged through their inclusion as assessors. Research has shown that family members, followed by nurses, are most accurate in their estimates of patients’ levels of symptom distress.16,31,32 Use of the SAS was found to facilitate communication among patients, family members, nurses, and doctors by providing a common and consistent language for reporting symptoms. Further testing of the SAS in nonpalliative populations such as patients in early stages of the cancer illness trajectory and individuals with other chronic diseases would be useful. Since this study, the SAS has formed the basis for ongoing research work including the Navigate Care Model.33 Toye and colleagues26 tested the SAS with residents in aged care facilities and found the SAS provided a brief but comprehensive overview of symptom distress that may prompt additional in-depth assessment. The SAS was considered a valid measure in frail aged people able to provided self reports. Lewin and colleagues,27 in a study of home-based palliative care, report the SAS as being useful for providing symptom data that can be used to audit care against established standards, to compare services and to inform funders or purchasers. At present, the SAS is being used by palliative care services across Australia involved in the Palliative Care Outcomes Collaborative (PCOC). PCOC is a voluntary quality Discussion This study tested the SAS in a variety of Western Australian palliative care settings: inpatient, consultative, and community based. Results indicate the SAS is easy to administer, in terms of its brevity and the short time required to administer it and with minimal missing data. It is likely to be a useful tool to guide clinical care. The SAS does not provide an in-depth assessment of individual symptoms, but serves as a screening tool to identify troublesome symptoms that warrant more attentive and immediate clinical investigation and comprehensive assessment. Internal consistency reliability and stability over time of the SAS were found to be acceptable. The SAS demonstrated construct validity by discriminating changes in expected symptoms among patients with different cancer diagnoses. The SAS also demonstrated sensitivity to detect changes in symptom distress over time. The variation in internal consistency as measured by Cronbach’s a suggests the different symptoms assessed by the instrument are not necessarily correlated in this population. This is expected because each cancer type and related treatment cause comorbidities and symptoms that are Table 5. Symptom Test-Retest Reliability Symptom Appetite Bowel Breathing Fatigue Insomnia Nausea Pain n r p 60 59 59 60 60 60 60 0.92 0.90 0.84 0.87 0.92 0.89 0.94 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 SD, standard deviation. 320 AOUN ET AL. initiative that aims to assist palliative care services to measure the standard and quality of care.28,34 To achieve this, consideration is given to the domains that will provide useful outcome measures for clinicians and the tools that best measure these outcomes. SAS has been chosen to routinely collect clinically meaningful data about patient physical symptoms because an extensive review of assessment tools25 showed that the SAS met the following criteria, compared with other symptom assessment tools mentioned at the start of this article: validated, efficient, and accurate in assessing patients; acceptable to patients and health care professionals; stable over time and quick to use; uses appropriate terminology and is easily understood by patients and family caregivers; suitable in the Australian context; balances the need for clinical use and research use; and able to be used across a number of care settings and with a variety of populations. It should be noted that it is also important to screen for psychological symptoms by using a complementary tool, but this is outside the scope of this study to describe. Conclusion This study has shown the SAS to be a reliable and valid method of symptom assessment that is brief, easy to use, and can be used in a variety of palliative care settings. The use of the SAS on a regular basis is recommended to assess patient symptoms, allowing a timely response to distressing symptoms. This formalized regular approach to symptom assessment may improve the treatment response time, enhancing patient care. The development of an assessment tool that can be used across a number of care settings will benefit cancer patients by providing a system of assessment that is universally accepted and utilized, and one that is easily understood by the patients and family caregivers. Appendix. Symptom Assessment Scale (SAS) Circle the number that best matches your experience No problem Insomnia Appetite problems Nausea Bowel problems Breathing problems Fatigue Pain Worst possible problem 0 1 2 3 4 5 6 7 8 9 10 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 0 1 2 3 4 5 6 7 8 9 10 0 0 0 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5 6 6 6 7 7 7 8 8 8 9 9 9 10 10 10 This scale measures how severe your distress or discomfort is, relating to each problem in the past 24 hours. Acknowledgments The authors would like to acknowledge the clinicians who participated in this study: Dr. Sarah Pickstock, Dr. Kevin Yuen, Sue Davis, Jo Blight, Annette Cummins, and Ellen Nightingale. Author Disclosure Statement No competing financial interests exist. References 1. World Health Organization. WHO Definition of Palliative Care. www.who.int/cancer/palliative/definition/en/. [Last accessed September 23, 2010.] 2. Bruera E, Kuehn N, Miller MJ, Selmser P, Macmillan K: The Edmonton Symptom Assessment System (ESAS): A simple method for the assessment of palliative care patients. J Palliat Care 1991;7:6–9. 3. Higginson IJ, McCarthy M: Validity of the support team assessment schedule: Do staffs’ ratings reflect those made by patients or their families? Palliat Med 1993;7:219–28. 4. McCorkle R: The measurement of symptom distress. Sem Oncol Nurs 1987;3:248–256. 5. Nekolaichuk C, Watanabe S, Beaumont C: The Edmonton Symptom Assessment System: A 15-year retrospective review of validation studies (1991–2006). Palliat Med 2008;22:111–22. 6. Richardson LA, Jones GW: A review of the reliability and validity of the Edmonton Symptom Assessment System. Curr Oncol 2009;16:55. 7. Chang VT, Hwang SS, Feuerman M: Validation of the Edmonton Symptom Assessment Scale. Cancer 2000;88: 2164–71. 8. Schulman-Green D, Cherlin EJ, McCorkle R, Carlson MD, Pace KB, Neigh J, Hennessy M, Johnson-Hurzeler R, Bradley EH: Benefits and challenges in use of a standardized symptom assessment instrument in hospice. J Palliat Med 2010;13:155–9. 9. Portenoy RK, Thaler HT, Kornblith AB, McCarthy Lepore J, Friedlander-Klar H, Kiyasu E, Sobel K, Coyle N, Kemeny N, Norton L: The Memorial Symptom Assessment Scale: An instrument for the evaluation of symptom prevalence, characteristics and distress. European J Cancer 1994;30:1326–1336. 10. Hearn J, Higginson IJ. Development and validation of a core outcome measure for palliative care: The palliative care outcome scale. Palliative Care Core Audit Project Advisory Group. Qual Health Care 1999;8:219–227. 11. McCorkle R, Young K: Development of a symptom distress scale. Cancer Nurs 1978;1(5):373–378. 12. Holmes S: Use of a modified symptom distress scale in assessment of the cancer patient. Int J Nurs Stud 1989; 26(1):69–79. 13. Kristjanson LJ, Leis A, Koop PM, Carriere KC, Mueller B: Family members’ care expectations, care perceptions, and satisfaction with advanced cancer care: Results of a multisite pilot study. J Palliat Care 1997;13:5–13. 14. Kristjanson LJ, Sloan JA, Dudgeon D, Adaskin E: Family members’ perceptions of palliative cancer care: Predictors of family functioning and family members’ health. J Palliat Care 1996;12:10–20. 15. Lobchuk MM, Kristjanson L: Perceptions of symptom distress in lung cancer patients: II. Behavioral assessment by primary family caregivers. J Pain Symptom Manage 1997;14: 147–156. 16. Lobchuk MM, Kristjanson L, Degner L, Blood P, Sloan JA: Perceptions of symptom distress in lung cancer patients: I. Congruence between patients and primary family caregivers. J Pain Symptom Manage 1997;14:136–146. 17. McCorkle R, Quint-Benoliel J: Symptom distress, current concerns and mood disturbance after diagnosis of lifethreatening disease. Soc Sci Med 1983;17:431–438. MEASURING SYMPTOM DISTRESS IN PALLIATIVE CARE 18. Peruselli C, Paci E, Franceschi P, Legori T, Mannucci F: Outcome evaluation in a home palliative care service. J Pain Symptom Manage 1997;13:158–165. 19. McCorkle R, Dowd M, Ercolano E, Schulman-Green D, Williams AL, Siefert ML, Steiner J, Schwartz P: Effects of a nursing intervention on quality of life outcomes in post-surgical women with gynecological cancers. PsychoOncology 2009;18:62–70. 20. Schulman-Green D, Ercolano E, Dowd M, Schwartz P, McCorkle R: Quality of life among women after surgery for ovarian cancer. Palliat Support Care 2008; 6:239–247. 21. Skrutkowski M, Saucier A, Eades M, Swidzinski M, Ritchie J, Marchionni C, Ladouceur M: Impact of a pivot nurse in oncology on patients with lung or breast cancer: Symptom distress, fatigue, quality of life, and use of healthcare resources. Oncol Nurs Forum 2008;35:948–954. 22. Rhodes VA, McDaniel RW, Homan SS, Johnson M, Madsen R: An instrument to measure symptom experience. Symptom occurrence and symptom distress. Cancer Nurs 2000;23:49–54. 23. Schneider SM, Hood LE: Virtual reality: A distraction intervention for chemotherapy. Oncol Nurs Forum 2007;34:39–46. 24. Kristjanson L, Pickstock S, Yuen K, Davis S, Blight J, Cummings A, Oldham L, Cousins K, Webster J, Dean A: Development and testing of the revised Symptom Assessment Scale (Final Report). Perth: Edith Cowan University, 1999. 25. Aoun S, Fournier C, Walker H: Literature review on symptom and functional assessment tools. Unpublished report prepared for the National Palliative Care Outcomes Collaboration (PCOC) by WA Centre for Cancer and Palliative Care. Perth, Western Australia, April 2007. 26. Toye C, Walker H, Kristjanson LJ, Popescu A, Nightingale E: Measuring symptom distress among frail elders capable of providing self reports. Nurs Health Sci 2005;7:184–191. 27. Lewin G, Haslehurst P, Smith J: Symptom pathways from referral to death: Measuring palliative care outcomes. Int J Palliat Nurs 2008;14:58–64. 321 28. Currow DC, Eagar K, Aoun S, Fildes D, Yates P, Kristjanson LJ: Is it feasible and desirable to collect voluntarily quality and outcome data nationally in palliative oncology care? J Clin Oncol 2008;26:3853–3859. 29. Nunnally J, Bernstein I: Psychometric Theory, 3rd ed. New York: McGraw Hill, 1994. 30. Carmines EG, Zeller RA: Reliability and Validity Assessment. Beverley Hills, CA: Sage Publications, Inc., 1979, p. 72. 31. Kristjanson LJ, Nikoletti S, Porock D, Smith M, Lobchuk M, Pedler P: Congruence between patients’ and family caregivers’ perceptions of symptom distress in patients with terminal cancer. J Palliat Care 1998;14:24–32. 32. Kurtz ME, Kurtz JC, Given CC, Given B: Concordance of cancer patient and caregiver symptom reports. Cancer Pract 1996;4:185–190. 33. Nightingale E, Kristjanson LJ, Toye C: Evaluating the Navigate Care Model: Clinical palliative care pathways based on anticipated care outcomes. Int J Palliat Nurs 2003;9:298– 307, discussion 307. 34. Eagar K, Watters P, Currow DC, Aoun SM, Yates P. The Australian Palliative Care Outcomes Collaboration (PCOC)—measuring the quality and outcomes of palliative care on a routine basis. Aust Health Rev 34:186–192. Address correspondence to: Samar M. Aoun, B.Sc.(Hons), M.P.H., Ph.D. Western Australian Centre for Cancer and Palliative Care Curtin Health Innovation Research Institute Curtin University GPO Box U1987 Perth, Western Australia 6845 Australia E-mail: s.aoun@curtin.edu.au