Background: Despite the wide use of the Short-Form Supportive Care Needs Survey Questionnaire (SCNS-SF34), the measurement invariance of the SCNS-SF34 across the main groups-gender and age-which might be of interest in the application of the instrument has never been confirmed. To provide an accurate assessment tool to evaluate the unmet needs of Chinese cancer patients, the present study aimed to assess the measurement invariance of the SCNS-SF34 across gender and age groups and to assess the validity and reliability of the Chinese version of the SCNS-SF34.
Methods: The SCNS-SF34 was administrated to 1106 Chinese cancer patients. Other instruments included the Memorial Symptom Assessment Scale-Short Form (MSAS-SF), the Short-Form-12 Health Survey version 2 (SF-12 v2) and the Hospital Anxiety and Depression Scale (HADS). Factor structure, internal construct validity, convergent validity, known-group validity and internal consistency were assessed.
Results: Our data fit the original five-factor model. Multi-group confirmatory factor analysis indicated measurement invariance across age and gender groups. The domains of the SCNS-SF34 had moderate correlations with the corresponding domains of the MSAS-SF, the SF-12 v2 and the HADS, which supported convergent validity. Of the 34 items, 33 had an item-total correlation that was corrected for an overlap of > 0.4 to support the internal construct validity. The SCNS-SF34 aptly differentiated patients by age and gender. The Cronbach's alpha coefficient ranged from 0.64 to 0.87.
Conclusions: We confirm the measurement invariance of the Chinese version of the SCNS-SF34 across gender and age group. It is a valid and reliable tool for evaluating the needs of Chinese patients with cancer.
Keywords: Measurement invariance; Reliability; Unmet need; Validity.