Answer to Question 1
A
Parenteral calcium may cause severe bradycardia in patients taking digoxin; therefore, the heart rate should be monitored closely. Concurrent administration of calcium chloride and pantopra-zole, lorazepam, or furosemide is not known to lead to drug interactions.
Answer to Question 2
A
Randomization helps prevent allocation bias, which can occur when researchers place subjects with desired characteristics in the study group and other subjects in the control group so that dif-ferences in outcome are actually the result of differences in subjects and not treatment. Compar-ing treatment outcome to no treatment outcome is the definition of a controlled study. The last two options describe the use of blinding in studies; blinding ensures that researchers or subjects (or both) are unaware of which subjects are in which group so that preconceptions about benefits and risks cannot bias the results.