Osmosis CATS

Submitted by Weiru Chang on
What is the Purpose of the Assessment?

Students struggle with the concept of osmosis and fluids and electrolytes.

Describe the necessity for this assessment

Fluids and electrolyte is essential for nursing school. Over half of the students do not understand osmosis.

Describe how the practice will be implemented

We created a pre-test (file attached) to assess where the problems in understanding the concept of osmosis may lie.  Our pre-text had 8 questions, some were taken from Bio 156, some from Bio 202, and some from NCLEX practice tests. The results show that:  Bio 156 scored 51% (n=36) on the pre-test; Bio 202 students scored 49%(n=72) on the pre-test(file attached). The result surprised us. How did students who took more biology classes do worse on the pre-test?

Interpret, compare, and describe the results

With the results,  we questioned how we are teaching the topic.  Dr. Parmiter and I compared our class notes and noticed that we use different terminology. In physiology and medicine, we use numbers and units of measurements to compare the fluid and electrolytes in osmosis.  We realized that misunderstanding comes from students mis-defining the variables, numbers, and  terminology.    

After analyzing, and reflecting on the outcome, what are the next steps?

Our next steps:

1. meet with nursing faculty.      2.align our courses with the nursing pathway.    3. Designing modules for pre-nursing students


Introductory Biology for Allied Health, Bio 156, is a course many students take for the nursing major.  This course teaches a number of concepts that are important and repeated throughout other biology prerequisite courses (Bio 201 Anatomy and Physiology I, Bio 202 Anatomy and Physiology II, and Bio 205 Microbiology), nursing block 1-4 courses, and the NCLEX, nursing certification exam.  The purpose of this CATS is to question whether the concepts we teach are retained through the courses. We decided to pick one topic and study this process. Osmosis is a concept that is taught throughout the sequence of courses and program. We made a pre-test and assessed students’ understanding of osmosis. The result was surprising, the students in Bio 202 (49%) did slightly worse than Bio 156 (51%).  The results have generated useful conversations and initiated changes to our pre-nursing course content/alignment.

Completed Full Cycle
Course Number
Bio 156
Bio 202
Attachment Size
osmosis-cats-report.pdf 111.64 KB
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Becky Baranowski Tue, 02/19/2019 - 8:48am

I love the collaboration you and Catherine are doing and how you are using a pre-test to see where students are when they come into your courses.  I have also tried to use common language in calculus that physics uses, this way students have an easier transition.  Thank you very much for taking time to submit this CATS.  

Catherine Cochran Tue, 02/19/2019 - 1:41pm


This is excellent research done by you and Dr. Parmiter!  I am glad to learn that you were able to pinpoint the source of misunderstanding:  the students mis-defining the terminology and variables.  Thank you for sharing!


Teri Graham Mon, 02/25/2019 - 10:01am

Thank you for sharing your experience through CATS.  I look forward to you sharing the results of the post-test and how your changes affect future students (pre/post again?) :-)