Validity of a food frequency questionnaire (preliminary results)

A low intake of antioxidant nutrients is associated with poor semen quality in patients attending fertility clinics

“…The FFQ was a modified version of the Harvard questionnaire (23) that was previously validated and adapted for adult Spanish populations (24,25). When comparing the nutrient intakes from the FFQ with those from four 1-week dietary records, the average correlation coefficients for 1-year validity and reproducibility of nutrient intakes were 0.47 and 0.40, respectively, a similar range to other established diet questionnaires (26).…”

Iodine Intake and Maternal Thyroid Function During Pregnancy

“…The questionnaire, an adapted version of the FFQ developed by Willett et al, 24 has been previously used and validated in the general population in Valencia (Spain). 25 Iodine values were obtained primarily from food composition tables from the US Department of Agriculture 26 and from additional information available for iodized salt in Spain. The production of iodized table salt has been regulated in Spain by law since 1982, but its use is not compulsory and its availability is not accompanied by a sustained educational campaign.…”

Retinol and α-Tocopherol in Morbid Obesity and Nonalcoholic Fatty Liver Disease

“…Dietary patterns were estimated using a food frequency questionnaire that has been previously validated in the Spanish population [22]. Weight and height were measured, and the BMI was calculated.…”