Development and validation of a knowledge questionnaire regarding the relationship between bacterial resistance and cancer among oncologists

Introduction: Bacterial resistance poses a significant threat to cancer patients due to their compromised immune systems and frequent use of antibiotics. Understanding oncologists' knowledge of this issue is essential for improving patient care. This study aimed to develop and validate a questionnaire assessing oncologists' knowledge of the relationship between bacterial resistance and cancer. 

Methods: A cross-sectional study involving 421 participants was conducted in Iraq from November 2023 to March 2024 across various cancer centers and oncology hospitals. A 41-item questionnaire covering eight domains—Risk Factors, Infections and Antibiotic Use, Mechanisms of Resistance, Impact on Drug Efficacy and Toxicity, Genetic Factors, Microbial Adaptation, Impact of Gut Microbiota, and Antimicrobial Stewardship—was developed. Content validity was evaluated by five experts. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were used to assess construct validity, while Item Response Theory (IRT) evaluated item performance. Reliability was measured using Cronbach's Alpha and Composite Reliability (CR). 

Key findings: The questionnaire showed strong content validity, with most items achieving a Content Validity Index (CVI) of ≥0.8. EFA identified eight factors, confirmed by CFA with acceptable model fit (CFI = 0.96, TLI = 0.95, RMSEA = 0.05). IRT indicated strong item discrimination and acceptable difficulty. Cronbach's Alpha was 0.88, with CR at 0.89. 

Conclusion: This validated 41-item questionnaire provides a reliable tool for assessing oncologists' knowledge of bacterial resistance among cancer patients. It helps identify knowledge gaps and guide interventions to improve oncology practice outcomes.