Assessing the invariance of a culturally competent multi-lingual unmet needs survey for immigrant and Australian-born cancer patients: a Rasch analysis.

PURPOSE: The purpose of this study was to assess the invariance of a culturally competent multi-lingual unmet needs survey. METHODS: A cross-sectional study was conducted among immigrants of Arabic-, Chinese- and Greek-speaking backgrounds, and Anglo-Australian-born controls, recruited through Cancer Registries (n = 591) and oncology clinics (n = 900). The survey included four subscales, with newly developed items addressing unmet need in culturally competent health information and patient support (CCHIPS), and items adapted from existing questionnaires addressing physical and daily living (PDL), sexuality (SEX) and survivorship (SURV) unmet need. The survey was translated into Arabic, Chinese and Greek. Rasch analysis was carried out on the four domains. RESULTS: Whilst many items were mistargeted to less prevalent areas of unmet need, causing substantial floor effects in person estimates, reliability indices were acceptable. The CCHIPS domain showed differential item functioning (DIF) for cultural background and language, and the PDL domain showed DIF for treatment phase and gender. The results for SEX and SURV domains were limited by floor effects and missing responses. All domains showed adequate fit to the model after DIF was resolved and a small number of items were deleted. CONCLUSIONS: The study highlights the intricacies in designing a culturally competent survey that can be applied to culturally and linguistically diverse groups across different treatment contexts. Overall, the results demonstrate that this survey is somewhat invariant with respect to these factors. Future refinements are suggested to enhance the survey's cultural competence and general validity.

A comparison of the FACT-G and the Supportive Care Needs Survey (SCNS) in women with ovarian cancer: unidimensionality of constructs.

PURPOSE: Health-related quality of life (HRQoL) and unmet needs (needs) questionnaires offer alternative perspectives for assessing cancer patients' concerns. We examined whether the conceptual differences underlying these alternative approaches yield corresponding empirical differences. METHODS: Eight-hundred and seventy-four women with ovarian cancer completed the Functional Assessment of Cancer Therapy scale (FACT-G; HRQoL) and the Supportive Care Needs Survey (SCNS-SF34; needs) every 3 months for 2 years. Correlational analysis, exploratory and confirmatory factor analysis (EFA/CFA), and Rasch analysis tested the relationship between patients' responses to similar domains and similar items across the two questionnaires. RESULTS: Strong correlations were found between items with virtually identical wording (0.67-0.75), while moderate to strong correlations (0.55-0.65) were found for those with very similar wording. EFA identified two common domains across the two questionnaires: physical and psychological. For each common domain, CFA indicated models involving a single construct with systematic variation within each questionnaire fit best. Rasch analysis including very similar items within the physical and psychological domains (separately) demonstrated strong evidence of unidimensionality. CONCLUSIONS: The high degree of similarity between patient responses to items addressing the same or very similar concerns suggests either that HRQoL and needs approaches do not reflect different constructs or that patients may not be able to differentiate between the severity of a concern and the level of need associated with that concern, especially when these are assessed in quick succession.