Dissertations (Open Access)

Date of Award

Summer 8-2020

Degree Name

Doctor of Philosophy in Nursing (PhD)


Sandra K. Hanneman, PhD

Second Advisor

Melanie McEwen, PhD

Third Advisor

Elda Ramirez, PhD

Fourth Advisor

Vincent R. Conti, M.D.


Background: Critical care nurses (CCNs) who care for postoperative cardiac surgery patients need specialty knowledge, for example, knowledge of atrial electrograms (AEGs). An inadequate audit trail exists for psychometric performance of instruments to measure CCN knowledge of AEGs. A 29-item survey previously pilot tested with a convenience sample of CCNs in the Pacific Northwest had a Kuder-Richardson-20 estimate of internal consistency of .75. The survey was revised to 20 items (14 knowledge and 6 AEG interpretation) and named the Drake Atrial Electrogram Assessment Survey (DAEGAS).

Objectives: The study objectives were to assess evidence for content validity (content validity index, CVI) and internal consistency (Cronbach’s α) and stability (correlation coefficient, r) reliability of the DAEGAS.

Methods: A panel of six AEG experts reviewed the DAEGAS for content validity evidence. The instrument was further revised to 19 items (13 knowledge and 6 AEG interpretation) based on expert feedback. Internal consistency and stability (test/retest; 2-week interval) reliability was assessed with 76 CCNs from the greater Houston metropolitan area. Analyses included descriptive statistics for demographics, content validity index (CVI), Cronbach’s α, and r. The a priori criterion for all psychometric tests was > .80.

Results: The CVI was .93. Cronbach’s α was .51 and test-retest r was .74. Cronbach’s α increased to .63 and r to .77 with removal of four items that had a negative item-total correlation.

Conclusion: There was adequate evidence of content validity, but reliability estimates did not meet the a priori criterion. Further development of the DAEGAS to improve reliability estimates and testing to estimate other forms of validity such as construct and/or criterion-related validity are recommended. Reliable and valid assessment of CCN knowledge of AEGs will require improved psychometric performance of the DAEGAS.


atrial electrogram, critical care, instrument, knowledge, psychometrics

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Nursing Commons