1. "The validity of our food frequency questionnaire was evaluated by comparison with food diaries in 192 women." Which type of bias are the study investigators trying to limit? The study investigators are trying to limit a type of bias called recall bias a type of information bias. Recall bias happens when "differential level of accuracy in the information provided by compared groups." (Aschengrau & Seage, 2020, p. 278)

2. If the correlation between the food frequency questionnaire and food diaries is poor, is it more likely or less likely that this type of bias is present? It is more likely that recall bias is present due to the inaccurate recall and reporting of information.

3. Ovarian cancers were identified either by self-reports or data from the National Death Index. Women or their next-of-kin were asked for permission to obtain and review pathology reports to confirm the diagnosis. Which type of bias are the study investigators trying to limit by confirming the ovarian cancer diagnosis?

4. "The follow-up rate was 97%." Which type of bias are the investigators trying to assess?

5.Based on the follow-up rate, is this type of bias likely?

6. Is the "Healthy Worker Effect" a concern in this study?

7. "Participants who left more than 70 items blank on the diet questionnaire were excluded from the analysis." Which types of bias were the study investigators trying to limit?

8. "All of this [dietary] information was collected prospectively..." What type of bias was avoided with prospective dietary data collection?

Hazard ratios for the association between Mediterranean Diet Score and ovarian cancer