tions were easily answered if the prescription drug
had its brand name derivedfrom the generic name.
Questions based on such similarities were easier
for students compared to questions based on other
similarities.
• Incorrect Choice based on Brand and Generic
Name Similarity (S
3
)
In this study, there were fewer cases where the
generic name of a particular drug was similar to
the brand name of another drug. With such ques-
tion types, students tended to select the incorrect
brand name. Thus, the more similar a generic
name was to the brand name of another drug, the
harder the question. In this report, questions based
on this type of similarity were effective and pro-
vided the next level of complexity for questions
exemplified by S
2
.
• Incorrect Choice based on Generic Name Simi-
larity (S
4
)
Answers were difficult to identify if the cor-
responding generic names were similar to the
generic name presented in the question. There-
fore, students tended to select the wrong answer
because the generic name and the generic name
they associated with a particular brand name were
similar.
2.2 Method for Measuring Name
Similarity
Brand names consist of three parts: stem, dosage for-
mat, and standard unit. For example, ‘Amaryl 1 mg
tablet’: the stem corresponds to ‘Amaryl’, ‘1mg’ to
the standard unit which expresses the active ingredi-
ent content, and ‘tablet’ denotes the dosage format.
Similarity of brand name parts was considered be-
cause pharmacists typically use them to identify a pre-
scription drug. In this method, brand name stems
were used to measure similarity. To generate brand
name stems, standard unit and dosage format was re-
moved according to the method proposed by Kimura
et al (M. Kimura, K. Nabeta, F. Tsuchiya, 2010).
In addition, an edit distance algorithm, commonly
used to compute character sequence similarities, was
employed to measure drug name similarity. Similar-
ity was defined as the number of times required to
change characters by insertion and deletion. Values
were normalized and subtracted from 1. If the value
was equal to one, the string comparison was said to
be identical; however, if the value was closer to 0, the
string comparison was unrelated.
2.3 Process Generation
The process used to generate questions based on drug
name similarity was as follows: 1) instructors input
eight parameters that are regarded as maximum and
minimum values for each similarity (i.e., S
1
, S
2
, S
3
,
and S
4
); 2) the computer randomly selects a prescrip-
tion drug name from a database that best matches
a condition, and the drug name is not equal to the
generic name and min
2
< S
2
< max
2
; 3) the com-
puter randomly selects three drugs that best match a
condition, and the brand names are not equal to each
other and min
1
< S
1
< max
1
, min
3
< S
3
< max
3
, and
min
4
< S
4
< max
4
; and 4) the computer generates a
question based on the generic name and template in-
put, creates brand name choices, and outputs the ques-
tion in an HTML file format.
3 EXPERIMENT
Association between question difficulty and name
similarity was assessed in order to evaluate the va-
lidity of the proposed method. Generated questions
were used in an experiment where the ratio between a
correct answer and answer time was determined. To
evaluate the method properly, an experiment was con-
ducted on 12 students in their twenties who lacked
pharmaceutical knowledge and attended the Depart-
ment of Engineering.
Eight similarity parameters were used in the ex-
periment and three cases were generated as shown in
Table 1. In Case 1, brand names in the choices are
similar to each other (S
1
). In Case 2, the generic name
is similar to the brand name of the answer choice (S
2
).
In Case 3, the generic name is similar to the brand
name of an incorrect answer choice (S
3
). Similarities
corresponding to S
4
, which rely on proper knowledge
of generic names, were not included in this experi-
ment given the participant’s background. Finally, five
questions were prepared for each of the three cases
presented.
Table 1: Question threshold patterns.
S
1
S
2
S
3
S
4
Case 1 0.7-1.0 0.0-0.5 0.0-0.5 0.0-0.5
Case 2 0.0-0.5 0.7-1.0 0.0-0.5 0.0-0.5
Case 3 0.0-0.5 0.0-0.5 0.7-1.0 0.0-0.5
During the experimental process, participants
were shown a table of generic and brand names and
given 150 seconds to familiarize themselves with
the content. They were then asked to answer 15
computer-generated questions. Answer time, defined
A PROPOSED METHOD FOR GENERATING QUESTION TESTS BASED ON PRESCRIPTION DRUG NAME
SIMILARITY
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