Development and Comparability of a Short Food-Frequency Questionnaire to Assess Diet in Prostate Cancer Patients: The Role of Androgen Deprivation Therapy in CArdiovascular Disease - A Longitudinal Prostate Cancer Study (RADICAL PC) Substudy

Background There are few concise tools to evaluate dietary habits in men with prostate cancer in Canada. Objective The aim was to develop a short food-frequency questionnaire (SFFQ) in a cohort of prostate cancer patients. Methods A total of 130 men with prostate cancer completed the SFFQ and a validated comprehensive food-frequency questionnaire (CFFQ). Both questionnaires were administered at baseline and 6 mo later. Results We found good correlation between the SFFQ and the CFFQ for seafood, dairy, egg, fruits, potatoes, grains, soft drinks, and processed meat (Spearman rank correlation >0.5). Moderate correlation was found for meat, sweets, vegetables, protein, and carbohydrates (Spearman rank correlation: 0.3-0.5). We found a weaker correlation for total fat measured by SFFQ and CFFQ (Spearman rank correlation <0.3). There was adequate reproducibility during the 6-mo follow-up among all food groups and nutrients, with the exception of meat. Conclusions Our SFFQ can be considered an appropriate tool to be used for measuring the habitual dietary intake of prostate cancer patients.