Purpose <p>Prostate cancer (PCa) remains a significant health burden as one of the most common cancers among men worldwide. Given the growing evidence of lifestyle’s impact on PCa progression, this study evaluates multidisciplinary experts’ feedback on a novel questionnaire assessing lifestyle factors potentially influencing PCa progression.</p> Methods <p>Developed through systematic literature reviews and insights from focus groups with clinical practice professionals, namely interns and specialists in urology and family medicine (FM), the questionnaire covers four domains: sociodemographic data, dietary habits, lifestyle factors, and clinical data.</p> Results <p>The questionnaire was evaluated by 25 professionals from the fields of public health, epidemiology, urology, and family medicine (FM), as well as by two linguists and two clinical psychologists. The questionnaire was first evaluated using a 5-point Likert scale for adequacy, accuracy, completeness, format, interest, usefulness, and confidence. Subsequently, each domain was also assessed individually for adequacy, accuracy, and completeness, using the same Likert scale, with qualitative feedback refining the questionnaire. Overall, this questionnaire received positive evaluations, with a mean score of 4.47 ± 0.72 and a median score of 4 or higher for each assessment. All domains achieved median scores of 5 for adequacy and accuracy, though completeness scored slightly lower in the lifestyle domain. Qualitative feedback highlighted the questionnaire’s relevance and clarity, while suggesting minor refinements.</p> Conclusion <p>These findings underscore the potential of this structured data collection protocol for exploring lifestyle-PCa associations, supporting future case-control studies, and advancing targeted prevention and intervention strategies for PCa risk management.</p>