Question

Question 8 (a)

In a prospective cohort study of the effect of ligament injuries on the risk for knee osteoarthritis using electronic questionnaires match each of the sources of bias below with the appropriate category.   

-A.B.C. Subjects with ligament tears were different in terms of gender and age compared to subjects without tears -A.B.C. People with OA were able to recall their knee injury history more precisely than those without OA -A.B.C. body mass index which can lead to OA was not measured

A. Selection bias B. Information bias C. bias due to confounding

Question 8 (b)

Although not covered in your text, non-experimental studies are prone to some significant sources of bias that affect the ability to determine cause and effect. Use whatever reputable resources you can find to match the following descriptions of bias:

-A.B.C. More subjects with asthma answer and asthma questionnaire than subjects without asthma in a cross sectional study -A.B.C. In a cross sectional study, subjects with low back pain remember their occupational exposures differently than subjects without low back pain -A.B.C. In a prospective cohort study the researchers loose contact with many of the subjects

A. Recall bias B. Bias due to attrition C. Response bias