Support Care Cancer DOI 10.1007/s00520-011-1351-1
ORIGINAL ARTICLE
Psychometric properties of the German version of the Short-Form Supportive Care Needs Survey Questionnaire (SCNS-SF34-G) Claudia Lehmann & Uwe Koch & Anja Mehnert
Received: 19 May 2011 / Accepted: 5 December 2011 # Springer-Verlag 2011
Abstract Purpose The recommendation to screen for distress and supportive care needs among cancer patients focuses on improving the quality, effectiveness, and efficiency of comprehensive cancer care. The purpose of this study was to test the psychometric properties of the German version of the Short-Form Supportive Care Needs Survey (SCNS-SF34-G). Methods One thousand forty-seven participants with heterogeneous tumor entities were recruited in inpatient and outpatient cancer care facilities (female, 51%; median age, 57 years; breast cancer, 26%; prostate cancer, 22%). Concurrent and divergent validity of the SCNS-SF34-G was analyzed through associations with measures of distress, depression, anxiety, and social support. Results Principal component analyses revealed five dimensions replicating the factorial structure of the original SCNSSF34 (health system and information, psychological, physical and daily living, patient care and support, sexuality needs) explaining 68% of variance. Cronbach's alpha values ranged from 0.82 to 0.94. Convergent validity was supported by significant correlations between all SCNS-SF34-G subscales and psychosocial burden. Divergent validity was indicated by marginal correlations with social support. The SCNS-SF34-G was able to discriminate patient groups with respect to sex and age but not regarding tumor stage. Conclusions The SCNS-SF34-G is an instrument with excellent psychometric properties for assessing supportive care needs among patients with various cancer entities. It seems to be useful to integrate the questionnaire into diagnostic C. Lehmann (*) : U. Koch : A. Mehnert Department of Medical Psychology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, W26, 20246 Hamburg, Germany e-mail:
[email protected]
assessment to tailor interventions according to patient needs. Further research is needed to gain knowledge of the development of unmet needs during the illness trajectory as well as of associations with offer and utilization of healthcare services. Keywords Supportive care needs . Psycho-oncology . SCNS-SF34 . Psychometric properties . Assessment
Introduction Since cancer patients can experience problems in every area of life throughout the illness trajectory, the cooperation of a multidisciplinary team of oncologists, general practitioners, nurses, psychologists, and social workers is recommended in international treatment guidelines to address all areas the patient is in need of support [1, 2]. To achieve this goal, a valid and precise assessment of the patients' medical condition and supportive care needs is essential. The evaluation of well-being is a relevant criterion as the extent of burden even with regard to somatic parameters such as nausea or pain can be measured only by the patients' self-report. Consequently, patient-reported outcomes (PROs) are an essential part of every clinical encounter to tailor interventions most effectively. PRO measures are self-report questionnaires developed to assess patients' experiences of disease and treatment-related symptoms including quality of life, distress, or satisfaction with care [3]. They are used in clinical trials to enhance knowledge about treatment benefits or risks and can support physicians in clinical care to facilitate patient-centered care [3]. PRO instruments measuring quality of life, distress, or psychosocial burden of cancer patients are well established. However, to gain a comprehensive picture of patients' condition, it is necessary not only to assess patients' symptoms and functioning but also to identify the level of perceived care
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needs since symptom assessment does not reveal to what extent lower functioning is problematic for the patient [4]. Research indicates significant associations among functioning, symptoms, and needs [5–7]. However, in a recent study which analyzed the concordance of well-being and needs, high discordance rates were found, particularly for patients with low functioning [8]. These results suggest that needs assessment should be added as an essential part of the distress screening that goes beyond the measurement of symptom burden only. There are various instruments to assess supportive care needs of cancer patients predominantly developed in Englishspeaking countries which differ from each other in covered need areas and approaches of validity and reliability testing [9]. One of the most comprehensive tools with respect to health status and aspects related to satisfaction with health care is the Supportive Care Needs Survey (SCNS) [9]. The SCNS [10] was derived from the 52-item Cancer Needs Questionnaire [11].
The supportive care needs survey The Supportive Care Needs Survey is available as a 59-item long form (SCNS-LF59) [10] and a 34-item short-form version (SCNS-SF34) [12], and exists in Korean, Japanese, and Chinese versions [13–15]. The long form as well as the short form of the self-report questionnaire measures patients' perceived type and magnitude of need for support in five domains: health system and information, psychological, physical and daily living, patient care and support, and sexuality needs. Existential and spiritual needs are covered by some items of the psychological domain (e.g., thoughts about death and dying) but are not assessed specifically. On a 5-point Likert scale, patients indicate if they are in need of support and the extent of need (10no need, not applicable; 20no need, satisfied; 30low need; 40moderate need; 50high need). The five-factor structure which accounts for 64% (SCNSLF59) respectively (resp.) 73% (SCNS-SF34) of total variance was supported by validity testing [10, 12, 16]. In a heterogeneous sample of 1,138 cancer patients, the SCNS-SF34 dimensions showed excellent reliability (Cronbach's α from .86 to .96), and its validity was confirmed both by exploratory and confirmatory factor analyses as well as by correlational analyses using the Distress Thermometer and the Hospital Anxiety and Depression Scale [12]. The five-factor solution was replicated by Okuyama et al. [14] in a Japanese sample of 408 breast cancer patients explaining 75% of variance. Reliability scores ranged from α00.87 to α00.96. In contrast to Boyes et al. [12] and Okuyama et al. [14], reliability and validity testing of the Chinese version of the SCNS-SF34 among 348 breast cancer patients showed a 33-item solution covering four dimensions of supportive care needs (54% variance explained): health system, information and patient support, psychological,
physical/daily living, and sexuality needs [15]. Internal consistencies ranged from α00.75 to α00.92. In Germany, cancer is the second most common chronic disease. Cancer incidence statistics show 426,800 new cancer cases per year and an enhanced 5-year survival rate between 61% and 62% for women and between 54% and 57% for men, including all cancer stages [17]. Although international distress screening measures such as the NCCN Distress Thermometer [18, 19] have been adapted into the German language, there is still a lack of standardized instruments assessing supportive care needs. Therefore, the objectives of the present study include examining the reliability and validation of the German version of the (SCNS-SF34-G), the amount of missing data, and the prevalence of needs in a sample of adult cancer patients with mixed cancer entities. The instrument was translated forward and backward into the German language supported by a native English speaker. We analyzed the factor structure and replicability of the dimensions, internal consistency, as well as concurrent and divergent validity through associations with measures of distress, anxiety, depression, social support, and detrimental interactions. Convergent validity was explored by associations between the SCNS-SF34-G domains and anxiety, depression, distress, as well as detrimental interactions. We hypothesized that the psychological domain would correlate highest with anxiety, depression, and distress as well as detrimental interactions compared to the remaining subscales. The validity threshold was set on r00.50 according to the definition of Hull [20] which is also recommended by Dawis [21]. Since the study of Wang et al. [22] showed no associations between levels of needs and perceived positive social support among lung cancer patients, we assumed low to zero correlations to be found between the SCNS-SF34-G subscales and positive support. Furthermore, the ability of the SCNS-SF34-G to discriminate between subgroups of patients with respect to age, gender, and cancer stage was explored. Differences were evaluated with sex, age (15% of the participants indicate highest or lowest scores), the results show floor effects for the health system and information, physical and daily living, and sexuality domain (17%, 29%, 36% resp. of patients achieved lowest scores). Thus, patients without supportive care needs (lowest category) in these domains cannot be distinguished from each other; content validity might be limited, and reliability might be reduced. On the other hand, one of the clinical priorities of the SCNS-SF34-G is to identify patients who are in need of support from those who have supportive care needs and to distinguish between them according to the extent of their needs. The absence of ceiling effects indicates that these objectives can be achieved despite the present floor effects. Correlation analyses showed that all SCNS-SF34-G subscales and particularly the psychological domain correlated significantly with measures of burden. However, associations were mainly small; only the correlations of the SCNSSF34-G psychological subscale with anxiety and depression
Domains of the SCNS-SF34-G
Distress Anxiety Depression HADS total Social support Positive support Detrimental interaction
Health system and information
Psychological
Physical and daily living
Patient care and support
Sexuality
0.28* 0.37* 0.33* 0.28*
0.39* 0.60* 0.55* 0.43*
0.36* 0.32* 0.36* 0.32*
0.24* 0.34* 0.32* 0.32*
0.18* 0.33* 0.31* 0.30*
−0.10** 0.14*
−0.14* 0.14*
−0.04 0.11*
−0.08** 0.12*
−0.09** 0.11*
Support Care Cancer Table 6 Contrasting groups by SCNS-SF34-G domains Characteristics
Age
