Development and Validation of a Symptom-Focused Quality of Life Questionnaire (KOQUSS-40) for Gastric Cancer Patients after Gastrectomy

Abstract

Purpose Patients who have undergone gastrectomy have unique symptoms that are not appropriately assessed using currently available tools. This study developed and validated a symptom-focused quality of life (QoL) questionnaire for patients who have received gastrectomy for gastric cancer. Materials and Methods Based on a literature review, patient interviews, and expert consultation by the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS), the initial item pool was developed. Two large-scale developmental studies were then sequentially conducted for exploratory factor analyses for content validity and item reduction. The final item pool was validated in a separate cohort of patients and assessed for internal consistency, test-retest reliability, construct validity, and clinical validity.Results The initial questionnaire consisted of 46-items in 12 domains. Data from 465 patients at 11 institutions, followed by 499 patients at 13 institutions, were used to conduct item reduction and exploratory factor analyses. The final questionnaire (KOQUSS-40) comprised 40 items within 11 domains. Validation of KOQUSS-40 was conducted on 413 patients from 12 hospitals. KOQUSS-40 was found to have good model fit. The mean summary score of the KOQUSS-40 was correlated with the EORTC QLQ-C30 and STO22 (correlation coefficients, 0.821 and 0.778, respectively). The KOQUSS-40 score was also correlated with clinical factors, and had acceptable internal consistency (> 0.7). Test-retest reliability was greater than 0.8. Conclusion The KOQUSS-40 can be used to assess QoL of gastric cancer patients after gastrectomy and allows for a robust comparison of surgical techniques in clinical trials.

Systematic review of health-related quality of life (HRQoL) issues associated with gastric cancer: capturing cross-cultural differences

“…Studies also reported on coping strategies, adjustment and acceptance of GC, nutritional status, unmet needs, and educational and self-care interventions. Six papers [23,[41][42][43][44][45], including 5 from non-East Asian countries, reported qualitative studies; three involved interviews with patients about symptoms experienced, such as gastrointestinal problems, fatigue, weight loss, and dietary restrictions, [41][42][43] and one about treatment preferences [44] whereby maintenance of selfcare and minimising toxicities were rated as priorities. Two incorporated qualitative methodologies as part of a questionnaire development process [23,45].…”

“…In addition to bespoke questions added to match the researchers' areas of interest, eight measures [27,28,45,[54][55][56][57][58], were developed in East Asia, and the PGAS45 [27] includes clinically important items selected by the Japan Post-gastrectomy Syndrome Working Party. Across all measures, the most widely assessed construct pertains to physical symptoms and this is particularly true for the GC or gastrointestinal specific measures which focus on gastrointestinal symptoms of disease and treatment such as gastrectomy.…”

Prospective multicentre randomised clinical trial comparing survival rates, quality of life and nutritional status between advanced gastric cancer patients with different follow-up intensities: study protocol for the STOFOLUP trial

“…In this study, KOQUSS-40 will be used to assess the QoL. 5 Frequent follow-up indicates frequent counselling, education and prescription, and these delicate management strategies help patients in self-controlling their symptoms, resulting in better physical, social and emotional functions. KOQUSS-40 focuses on postgastrectomy symptoms and we will evaluate whether there is a significant difference in KOQUSS-40 questionnaire scores in individuals with different follow-up intervals.…”

“…QoL will be assessed using three types of questionnaires; the KOrean QUality of life in Stomach cancer patients Study group-40 (KOQUSS-40), the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ) Core 30 (C30), and the stomach cancer-specific module (EORTC QLQ STO22). [5][6][7] KOQUSS-40 is a symptom-focused questionnaire for patients undergoing gastrectomy for Open access gastric cancer. It consists of 40 items in 11 domains and its scoring ranges from 0 (the worst) to 100 (the best) for each domain.…”

Patient-reported gastrointestinal symptoms following surgery for gastric cancer and the relative risk factors

“…At present, radical gastrectomy is the first-line treatment for GC that can prolong patients’ survival time ( 3 , 4 ). As surgery for GC gradually shifts toward minimally invasive approaches that can minimize trauma and postoperative complications and accelerate recovery ( 5 , 6 ), postoperative gastrointestinal symptoms (PGISs) such as abdominal distention, pain, and vomiting continue to exist that affect quality of life ( 7 ).…”