calculations with accuracy. Many errors may simply be because nurses have limited skills in
doing simple medication calculations, and fixing these skills may improve the system and create
safer nurses (Polifroni et al., 2005).
Nurses' Mathematics Ability
Many medication errors are related to dose errors and it is documented that nurses are not
good at mathematics (Calliari, 1995; Gladstone, 1995; Grandell-Niemi et al., 2001; Jukes &
Gilchrist, 2006; Lee, 2001; Wright, 2006). Jones (2009) stated, "Nurses poor mathematical
competency has been identified as a key cause of medication administration errors" (p. 41).
McMullan et al. (2010) found no statistical significant difference between the medication
calculation ability of registered nurses (RNs) and nursing students; the failure rate was 45% and
55%, respectively, on a mathematics test. They also administered a 20-item medication
calculation test to the same sample of RNs and nursing students, comparing age, status, and years
qualified with calculation ability; no significant relationships were found between the variables
except that the participants who were older than 35 did significantly better (p = 0.028). The
authors speculated that perhaps anxiety about performing mathematics influences performance.
Bayne and Bindler (1991) developed a 20-item instrument in 1984 to measure dosage
calculation skills of nurses and nursing students, and it has been used in several research
projects. In 1991, Bayne and Bindler studied 110 nurses to determined that there was a
significant relationship between the nurses' comfort level and medication calculation ability (F
13.0518, p = 0.000), and the comfort level showed significant differences between the categories
of comfort and calculation ability (comfort level above average and below average, p = 0.0001;
above average and average, p = 0.0060; average, and below average, p = 0.0029). Nurses could
predict skill level as above average, average and below average with "great" accuracy (F =
Melius, Joyce. Mathematics Anxiety and Mathematics Self-efficacy in Relation to Medication Calculation Performance in Nurses. Denton, Texas. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc115119/. Accessed March 11, 2014.