Full text of DOI:10.1592/phco.22.12.1036.33601

P RA C TIC E I N S IG H TS
Drug-Information Software for Palm Operating System
Personal Digital Assistants:
Breadth, Clinical Dependability, and Ease of Use
Shelly J. Enders, Pharm.D., Jason M. Enders, Pharm.D., and Sheldon G. Holstad, Pharm.D.
Study Objective. To examine the breadth, clinical dependability, and ease of
use of drug-information software programs for personal digital assistants
that incorporate the Palm operating system.
Design. Prospective evaluation with descriptive analysis.
Methods. Nine drug-information software programs were evaluated for
breadth, clinical dependability, and ease of use, based on responses to 56
questions.
Results. Breadth of information (percentage of questions that could be
answered) was 32–75%; LexiComp Platinum was the leader in this
category. Clinical dependability (factual completeness) of information was
6
6.7–100%; LexiComp Platinum led this category as well.
MobileMicromedex provided the narrowest breadth of information and the
least clinically dependable information. Time to locate an answer to posed
questions averaged 17.5 ± 4.98 seconds. The fastest retrieval time was
achieved by Davis ’s Drug Guide for Physicians (12.1 sec). Tarascon ’s
Pharmacopoeia required the fewest viewed PDA screens to locate the
requested information (3.3 screens). Cost of programs ranged from free to
$
129.95. Cost was not related to breadth or clinical dependability.
Conclusions. LexiComp Platinum offered the greatest breadth of information
and the most clinically dependable content. MobileMicromedex was the
least helpful of these products for answering straightforward drug-
information questions.
(
Pharmacotherapy 2002;22(8):1036–1040)
We are well into the age of the information
explosion, and information technology is no
longer a novelty. Information technology
advances have influenced many aspects of the
practice of medicine and pharmacy. Personal
digital assistants (PDAs) are one example of the
rapidly changing information technology world.
Use of these products ranges from 2–3% in the
general population to 10–15% in the medical
profession. The medical profession has turned
to PDAs for several reasons, including flexibility,
1
accessibility, and usability.
Physicians,
pharmacists, nurses, and health care students
scramble to deliver accurate drug information on
demand without interrupting health care
delivery.
The PDA, which can fit into a pocket, offers a
convenient way to access information. An
important role for PDAs in health care is drug-
information retrieval. Clinicians face an ever-
From the Pharmacy Practice Division, St. Louis College of
Pharmacy, St. Louis, Missouri (Drs. S. Enders and Holstad);
and the Department of Pharmacy, St. Luke ’s Hospital,
Chesterfield, Missouri (Dr. J. Enders).
Supported by St. Louis College of Pharmacy Research
Incentive Fund #125.
Address reprint requests to Shelly J. Enders, Pharm.D., St.
Louis College of Pharmacy, Pharmacy Practice Division,
4
588 Parkview Place, St. Louis, MI 63110.

DRUG-INFORMATION SOFTWARE FOR PDAs Enders et al
1037
expanding pharmacology knowledge base that
includes new drugs and changing information
about dosages, adverse reactions, and drug-drug
interactions. In the wake of the September 11th
disaster, pharmacists assigned to Disaster Medical
Assistant Teams used PDAs as “desk” references
for drug information. The senior pharmacist of
the teams relied on a PDA to determine generic
names of the trade-name drugs that the rescue
workers were taking and made recommendations
to other clinicians for alternative drugs. These
two standard resources (i.e., product-specific
package inserts, practice guidelines, American
Hospital Formulary Service, Drug Facts and
Comparisons, MICROMEDEX DRUGDEX and
DRUG-REAX, Drug Interaction Facts, and
5
–10
Evaluation of Drug Interactions).
Hand-held
drug-information programs were searched for
facts pertinent to the question and compared
2
drugs were supplied to the teams.
Dosing
A study found that drug-information software
programs for PDAs save time and help inform
both professionals and patients. The study’s
authors noted a trend toward a decrease in
adverse drug reactions that resulted from using
the technology. Drug-information programs on
PDAs allow for information to be delivered on
demand.
What is the infliximab dosing range for treatment of
rheumatoid arthritis?
What is the dose of celecoxib for treatment of familial
adenopolyps?
Length of treatment
What is the recommended length of treatment of an
uncomplicated UTI when treated with ciprofloxacin?
What is the length of treatment with warfarin for a
DVT?
3
Numerous documents available on the Internet
and in printed form describe the use of PDAs in
everyday medical practice for patient tracking,
prescribing, performing medical calculations, and
providing medical and drug information. One of
the most comprehensive of these reports
inventoried specific features of five drug-
information software programs for PDAs. This
assessment indicated whether or not each of the
programs contained information on adult,
pediatric, and generic dosage forms; contra-
indications and precautions; drug interactions;
pregnancy class; drug metabolism and excretion;
Administration
What are the proper dosing instructions for
alendronate?
What are the specific dosing instructions for indinavir
to prevent adverse drug reactions?
Adverse effects
What specific signs or symptoms of rhabdomyolysis
may be associated with atorvastatin?
Is severe depression a side effect of Accutane?
Scheduling and pricing
What is the cash price for Viagra 50 mg #10?
Is Midrin a controlled substance?
Contraindications and precautions
Can metformin be given to a patient with heart
failure?
Can sumatriptan be given to a patient with
uncontrolled hypertension?
4
and adverse reactions. It also briefly summarized
each of the programs with regard to size and
compatibility of software, expansion card
Indications
support, and Windows or Palm operating system
What are the indications of niacin?
Is Tri-Levelen indicated for treatment of acne?
4
(
OS) requirements. It did not address clinical
applications of the drug information. Therefore,
we sought to compare the breadth of coverage
and clinical dependability of drug-information
software programs that incorporate the Palm OS
for PDAs.
Availability
What formulations of Ditropan are available?
Is a form of doxycycline available specifically for IM
injection?
Drug interactions
Is there a clinically significant drug interaction
between omeprazole and itraconazole?
What is the significance of the interaction between
Viagra and nitrates?
Methods
Fifty-six questions (Figure 1) were developed.
These questions reflect issues that are applicable
to daily practice in both inpatient and outpatient
settings from broad specialties and subspecialties
Monitoring
What are the recommendations for management of
INR of 4.0?
What baseline labs should be obtained before starting
amiodarone therapy?
(
e.g., infectious disease, internal medicine,
primary care, and critical care). Before
evaluating the PDA programs, we documented
factual responses to each question. A response
was considered factual if confirmed by at least
Figure 1. Sample of posed questions for the classifications
of evaluated drug-information software programs. UTI =
urinary tract infection; DVT = deep vein thrombosis; IM =
intramuscular; INR = international normalized ratio.

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PHARMACOTHERAPY Volume 22, Number 8, 2002
a
Table 1. Characteristics and Performance of Nine Drug-Information Software Programs
Clinical
Mean
Mean
Breadth Dependability Time
Screens
(no.)
4.2
Cost
($)
49.95
Size
Expansion Card
Compatibility
Handspring, Sony
Memory Stick, Palm
M5xx SD cards
b
c
b
Program
LexiComp Platinum
(%)
(%)
(sec)
16.6
(mb)
c
75.0
100.0
2-4
Tarascon’s
Pharmacopoeia
57.1
49.8
90.6
84.3
15
3.3
4.6
Free
0.9
2.3
Not compatible
d
MosbyDrugs
17.7
64.95
Palm M5xx, Clie, Visor,
Handera expansion
memory cards
ePocrates
41.1
37.5
91.3
80.0
13.9
12.1
3.6
3.0
Free
1.3
1.9
Not compatible
Davis ’s Drug Guide
for Physicians
75.00
Palm M5xx, Clie, Visor,
Handera expansion
memory cards
e
PDR 2001
37.5
35.7
85.7
95.0
29.2
19.6
8.5
6.3
129.95
75.00
6.4
Not compatible
Physician ’s Drug
Handbook
2.1
Compact flash card
(e.g. TRG Pro) or
Visor memory
expansion card
A to Z Drug Facts
mobileMicromedex
33.9
32.1
78.9
66.7
18.4
14.9
3.7
3.6
49.95
74.95
1.8
1.4
Palm M5xx, Clie, Visor,
Handera expansion
memory cards
Not compatible
OS = operating system; PC = personal computer.
a
Data as of January 7, 2002.
Compatibility for Palm operating system only.
b
c
Depending on view selected at download.
d
Program downloaded onto SanDisk Secure Digital Expansion Card.
Includes full databases and Franklin Reader.
e
against the gold-standard responses. Questions
were designed to assess dosing (16 questions),
administration (9), adverse drug reactions (6),
scheduling and pricing (5), contraindications and
precautions (5), drug interactions (4), indications
using a Palm m505 PDA (Palm, Inc., Santa Clara,
CA) with a SanDisk 16 megabyte Secure Digital
expansion card. Programs were selected for
evaluation if they were compatible with the Palm
OS and were available from commercial vendors.
Installation of the programs onto the expansion
card was verified for each software package
claimed by the manufacturer to support this
option. All software programs were acquired
within a 2-week period to minimize variability in
time-sensitive content. Each question was
evaluated once for each program to enhance
consistency of evaluation between programs.
(
4), length of treatment (3), availability (3), and
monitoring (2).
An evaluation form was created to record
performance of the selected drug-information
software programs. The form provided fields for
drug-information content, ease of use, cost, and
memory requirement (i.e., megabyte space
requirement). The content portion of the form
offered fields to indicate whether or not the
software provided any of the requested
information, if the information provided was
complete, and if incomplete, what information
the program did provide. These measures were
defined as breadth and clinical dependability,
respectively. Ease-of-use data consisted of time
Once all questions were evaluated for all
programs, descriptive analyses were performed to
assess the performance of each program. Range
(
median) values were reported for breadth and
clinical dependability. Mean ± SD values were
reported for ease of use (time and number of
screens viewed).
(
sec) to locate an answer to the question posed
and number of screens visited before locating the
information or concluding the search.
Results
Programs were assessed by a single evaluator,
Nine drug-information software programs were

DRUG-INFORMATION SOFTWARE FOR PDAs Enders et al
1039
Table 1. (continued)
Palm OS
Clinical Dependability
Clinical dependability was defined as the
factual completeness of the answers that the
software programs provided. This was calculated
as a percentage, based on the number of
questions to which the programs provided a
complete answer as verified by standard
resources. The percentage of clinically
dependable information among the programs
ranged from 66.7–100% (median 85.7%).
LexiComp Platinum provided factually complete
information for all questions that it answered; it
thus was identified as the most clinically
dependable program. Of the answers provided
by mobileMicromedex, only 66.7% were factually
complete, making this the least clinically
dependable program evaluated. The most
clinically dependable types of drug information
provided by the software programs were
contraindications and precautions (100%), length
of treatment (100%), and monitoring (100%).
These were followed by drug interactions (95%),
drug scheduling and pricing (95%), adverse drug
reactions (92%), indications (86%), availability
or Pocket PC
Compatibility
Updates
Manufacturer
Lexi-Comp, Inc.
Unlimited
for 1 yr
Both
Unlimited
Quarterly
Palm OS
Palm OS
Tarascon Publishing
Mosby Publishing
Unlimited
Palm OS
Both
ePocrates
Unlimited
for 1 yr
F. A. Davis Company
No updates
No updates
Palm OS
Palm OS
Franklin Publishing
Springhouse Publishing
Unlimited
Quarterly
Both
Facts and Comparisons
MICROMEDEX
Palm OS
(
85%), and dosing (84%). The programs were
least clinically dependable with regard to
questions or scenarios about administration
(78%).
evaluated. Data were collected and reported as
breadth, clinical dependability, and ease of use.
Cost, size, and update provision for the programs
also were recorded. Results are presented in
Table 1.
Ease of Use
Ease of use was defined as time to locate an
answer to the question posed and number of
screens visited before locating the information or
concluding the search. The time to locate
answers, or to determine that the software did
not provide the requested information, was
approximately 12–29 seconds (mean 17.5 ± 4.98
sec). Retrieval time was not related to breadth or
clinical dependability. Davis ’s Drug Guide for
Physicians required the least time for information
retrieval, with an average of 12.1 seconds. The
mean time to retrieve information with PDR
Breadth
Breadth was defined as the expansiveness of
information provided by the selected programs.
This was determined by calculating the
percentage of questions that could be addressed,
although not necessarily completely or
accurately, by each program. Breadth ranged
from approximately 32–75% (median 37.5%).
LexiComp Platinum, which provided answers to
7
5% of the posed questions, was considered to
2
001 was 29.2 seconds, which was 10 seconds
provide the greatest breadth of clinical content.
MobileMicromedex, which answered only 32% of
the questions, displayed the least amount of
clinical information. LexiComp Platinum, the
most comprehensive product, provided
information on all 10 categories of drug-
information questions. MobileMicromedex, the
program with the narrowest breadth, often failed
to provide information on drug interactions,
adverse drug reactions, length of treatment, drug
scheduling and pricing, and monitoring.
more than the average software program. One
study found that most surveyed clinicians using
ePocrates for drug information located the
3
information in less than 20 seconds. Our
findings are consistent with this observation.
The number of screens viewed before locating
the information in question or to determine that
the software did not provide the information
ranged from 3.3–11 screens (mean 4.5 ± 1.8
screens). No relationship between screens
viewed and breadth of programs was observed.

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PHARMACOTHERAPY Volume 22, Number 8, 2002
of major institutions and medical schools to
Cost and Size
equip students with PDA devices and
accompanying drug-information programs for
use in education and clinical practice.
MICROMEDEX reported providing 650 Harvard
The programs ranged in cost from free to
129.95. The size of the programs, as reported
$
by the manufacturers, were 0.892–6.13
megabytes. We did not find the more expensive
programs to provide more breadth or to be more
clinically dependable. Nor did the least
expensive programs have narrower breadth or
less clinical dependability. Similarly, size of the
software was not associated with content breadth
or clinical dependability.
1
1
medical students with its mobileMicromedex.
With so many clinicians relying on drug-
information software programs for PDAs and
because drug information is crucial to patient
care, the information provided should be not
only expansive but also clinically dependable and
easy to retrieve.
Our evaluation identified LexiComp Platinum
as the most comprehensive and clinically
dependable of the nine PDA drug-information
software programs that we assessed.
MobileMicromedex and A to Z Drug Facts
performed poorly and are not recommended for
clinical use at this time. It must be remembered
that this is the first evaluation of its kind;
moreover, it is a relatively small and descriptive
study. Purchasing decisions should not be based
solely on this information. Rather, the analysis
should inform clinicians that differences may
exist between drug-information software
programs and further study may be warranted.
Discussion
We acknowledge that a systematic or
methodological bias could exist in this study.
Our tests consisted of only 56 questions, which is
a small number in relation to the immense body
of drug information available. Furthermore, our
questions were not standardized or reviewed by
an expert panel. However, we consider the 56
questions to provide a representative sample of
straightforward, generalist, drug-information
questions that any product marketed as a drug-
information reference should be capable of
answering. The continuous updating of PDA
drug-information programs make it impossible to
reproduce the exact results of our study, which
was performed in October 2001. We wish to
emphasize that our findings were valid at the
time of this evaluation and should not be
extrapolated to earlier or later software versions.
Some of the variation we observed may reflect
specific objectives of manufacturers. In
particular, PDR 2001 is limited to information on
indications approved by the Food and Drug
Administration. This may explain why its
breadth is narrower than that of programs with
no such statutory limitation. None of the other
programs indicated comparable limitations.
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