I did a search but couldn't find a discussion on this exact subject, so here goes:
Is one method truly better than the other or is it (like most things) a matter of personal preference? I've been messin' around with both using Pickar's "Dosage Calculations" for ratio/proportion and Medication Math for Nursing Students, http://www.alysion.org/dimensional/analysis.htm#guide, for DA.
From my perspective, RT is way more comfortable for me than DA. I get so confused with how to line up the pieces of DA that I simply give up on it and just go to the formulas of RT which yields the answers quickly (and to me simply).
Hmmm, I guess my real question is, what method will my school want me to use? The book we're supposed to get is Calculate with Confidence (which is on its way now) that includes instruction in both methods .
I'm figuring that if I consistently get the right answers, the instructor won't really care what method I use....
RP drives me nuts!!!!! But DA not that I get!!! I think as long as you get the right answers...it won't matter...but I would ask. I like D/H for short, simple little things too. We called it DO..DA dose ordered/dose on hand X's amount
Here is a simple way to figure out a medication problems in division:
Desired
--------
Have
That is desired divided by have..Very simple!!
That works if your problem is a simple 1-step calculation. But some real-life situations have multiple steps before you get to that point. Real-life situations don't always present themselves in the same format that your previous faculty used for test questions. When that happens, the DA users seek out the RP folks to help them figure out what to do.
Of course there are exceptions to that. Some DA users also have a good grasp of fundamental mathematics and the relationships between quantities. Those DA users are successful at solving all types of problems. However, some nursing students with math aversion rely too heavily on "quickie formulas" and "shortcuts" without really understanding the math that underlies them. They get through school OK and do OK in most common clinical situations in which the systems are in place to minimize their need for mathematical understanding. But they never become the leaders or resource people in that aspect of practice because they lack a fundamental understanding.
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emtb2rn, BSN, RN, EMT-B
2,942 Posts
ahhh, so if I divide what I desire by what I have, I'll know what I need. Yeesh, the story of my life.....