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Home Q & A Board Biology-Related Homework Help Medicine Nursing and Clinical
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rachel787 rachel787
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6 years ago
A study is examining the effect of a new antilipemic drug, compared with placebo, on lipoprotein levels in postmenopausal women.
 
  Which of these actions represents the researcher's attempt at constancy in data collection to control extraneous variables?
  a. Drawing the serum lipoprotein levels of all subjects at the same time of day
  b. Having the same phlebotomist draw serum lipoprotein levels of all subjects
  c. Using the same room for drawing blood for lipoprotein levels of all subjects
  d. Ensuring that all subjects are postmenopausal women taking lipid-lowering medication
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Nickluna@msn.coNickluna@msn.co
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6 years ago
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rachel787 Author
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6 years ago
Thanks
Natalie Price
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Yesterday
this is exactly what I needed
missnoname
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2 hours ago
You make an excellent tutor!
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