See the first line on that tab:
That's referring to the questionnaire with the questions I want to see. And I want to see how those questions have changed over the decades.
They can't draw any supposed conclusions about the effect of different types of fats if they haven't even been separating the different types of fats in their questions. Compounded by the fact that even once researchers started to understand that there were differences, the people they were asking either didn't understand or had no way to identify what they were actually eating.
Semi-quantitative food frequency questionnaire (diet in past year)
That's referring to the questionnaire with the questions I want to see. And I want to see how those questions have changed over the decades.
They can't draw any supposed conclusions about the effect of different types of fats if they haven't even been separating the different types of fats in their questions. Compounded by the fact that even once researchers started to understand that there were differences, the people they were asking either didn't understand or had no way to identify what they were actually eating.