The way forward in package insert user tests from a cro's perspective
The Way Forward in Package Insert User Tests
Introduction: A significant increase in thety to locate information, thus putting people offamount of text in package inserts has been ob-from reading the contents (P ≤ 0.021). served over the last years. This study investigat-Discussion: The results suggest that decreasinged the consequences of this increase. Method:the amount of text is a key factor, whereby aFive package inserts available on the Germanmaximum of 1,500 words per package insertmedicine market in 2002 and five developedshould be the aim. Conclusion: The way forwardJoerg Fuchs model versions were investigated in a crossoverin package insert user testing is to concentrateprocedure using the written readability test. on patient requirements and package insert im-Results: The more extensive the package inserts,provements. Appropriate solutions are requiredthe worse patients feel informed. Increasing thefor the further development of guidelines, tem-amount of text significantly decreases the abili-Key Words
inserts that comply with the laws and guide-
lines. Beyond these groups, there are the na-
Since Directive 2004/27/EC came into force,
tional and supranational agencies that monitor
Correspondence Address
package inserts of medicines that are sold in the
to ensure package inserts and their user tests
European Union require user tests to ensure
comply with legal requirements. Therefore, the
that they are legible, clear, and easy to use (1).
task of a contract research organization (CRO)
One possible way to carry out these tests is the
is to support the pharmaceutical companies to
verbal face-to-face interview method, developed
develop and test package inserts that meet the
by the Australian communications researchers
requirements of each stakeholder group. This
Sless et al. (2,3). Using this method, 12 to 15
EMEA-CMD(h) Workshopon User Testing, December
questions concerning the package insert key
which cannot always result in the most appro-
messages are posed orally by an interviewer to a
priate package insert for every patient.
minimum of 20 medical laymen divided into two
In comparison to European package inserts,
which are delivered to patients in the packaging
of each over-the-counter and prescribed medi-
with the guidelines and if they are able to detect
cine, package inserts in the United States—also
problems in locating and understanding infor-
called prescription drug labels—are primarily
mation (2). One example is the written readabil-
written to give health care professionals the in-
ity test, which was developed and validated in
formation they need to appropriately prescribe
the PAINT1 survey. In this method the test par-
medicines (5). However, both the European and
ticipants are given the instructions and a mini-
US package inserts have grown over the years in
mum of 15 questions regarding the package in-
length, detail, and complexity. Therefore, appro-
sert key messages using a questionnaire (4).
priate improvements and measures, such as user
Different stakeholders are involved in package
inserts and their associated user tests, although
Currently, there are no published results
patients form the key group in Europe. Patients
available regarding what can be achieved with
should be able to locate, understand, and use
the package insert user tests required in the Eu-
the information provided in the package in-
ropean Union. Table 1 provides optimizations of
serts. Other interested parties are the pharma-
four selected aspects that one CRO company
ceutical companies, who must create package
has achieved using the written readability test
Drug Information Journal, Vol. 44, pp. 119–129, 2010 • 0092-8615/2010
Submitted for publication: February 2, 2009
Printed in the USA. All rights reserved. Copyright 2010 Drug Information Association, Inc.Package Insert Optimizations Through the Most Recent User Tests Carried Out by PAINT-Consult Using the Written Readability Test (N = 40, English and German Package Inserts) Original Package Final Package Inserts (n) Inserts (n) Difference (%)
Long sentences (over 20 words per sentence)
*All difficult words were explained.
method. On average, the number of difficult
the PAINT1 survey results was done to investi-
words in the first package inserts provided by
gate the advantages and disadvantages of this
the pharmaceutical companies are reduced,
from 86 to 14 in the final tested versions. This isa difference of 84% (10). In addition, the 14 re-
maining difficult words are always explained.
The PAINT1 study was a written readability test
There are maximum and minimum results.
using a questionnaire consisting of 15 ques-
tions relating to the package inserts’ key mes-
clients, who have learned from the user test
sages and 17 questions concerning the partici-
company’s recommendations and test results to
provide better package inserts. This is a clear
Five original package inserts, available on the
German medicine market, and five previously
Another aspect is the amount of text. On aver-
developed model versions were investigated
age, the number of words contained in package
from September 2002 to April 2003. The mod-
inserts was reduced by 20% (Table 1) (10). One
els contained the same information as the origi-
survey with patients and another with medical
nals; however, they were optimized using a set of
and pharmaceutical experts showed that this
quality criteria such that the amount of text was
text reduction meets patients’ and experts’ re-
reduced to one page of A4 paper, printed on
quirements, as both want the text of package in-
both sides. Furthermore, the models contained
serts to be shorter and limited to only essential
an optimized design and a larger font size of 11
points (11). However, the current situation indi-
cates there has been a large text increase over
The study was a crossover comprehensibility
the last years, due to new directives, templates,
test in two rounds with a break between each
round of a minimum of 4 weeks. In the first
about the medicines. Therefore, a subanalysis of
round, half of the participants received an orig-
inal and the other half a model version. The ver-
• The percentages of information not located, incor-
sions were swapped in the second round so that,
rectly comprehended information, the time need-
at the end of this study, every person had tested
ed to locate the information, and the personal
an original and the corresponding model pack-
Relationships between participants’ demo-
Percentages for information not found and
graphic background and their opinions relating
incorrectly comprehended information were
to the package inserts were calculated using the
determined for the total of tested key messages
Cramer V calculation procedure from the SPSS
of each package insert. Furthermore, the medi-
14.0 statistics program for both package insert
an of the time required to locate all 15 answers
groups—originals and models. In addition, for
testing differences, Pearson’s chi-square test
In the section that addressed the partici-
was used. Afterward, Pearson’s correlation coef-
pants’ personal opinions of the package inserts,
ficients were also calculated for each package
each participant used a five-point scale to as-
sess the comprehensibility, legibility, complexityof information, clarity and structure, and their
confidence in the described medicine. The par-
In the first round, 1,105 people participated,
ticipants’ answers were coded as follows:
and of these 1,057 took part in the second test
“yes” = 1, “mostly yes” = 2, “other” = 3, “mostly
round (age 10–92 years; average 38 years) (4).
no” = 4, and “no” = 5. Medians were calculated
Figures 1 and 2 illustrate that the participants
for each of the 17 questions relating to the per-
located the information in each model package
insert significantly better than in the corre-
Afterward, Pearson’s correlation coefficients
sponding original version. There was a very high
were calculated using the SPSS 14.0 statistics
correlation between locatability in the original
package inserts and the amount of text they
• The package insert specifics, such as the amount of
contained. An increase in the number of words
in the originals led to a significant decrease in
Relationship between theamount of text in packageinserts and the percentageof not located informationfrom all 15 tested key mes-model; 1, Enalapril; 2,Ibuprofen; 3, Paracetamol
Percentage of Tested Information Not Located
Relationship between theamount of text in packageinserts and the time neededto locate all 15 tested keymessages (17). Definitions
Time Required to Locate Tested Information (min)
ability to locate the contents (P = 0.019), with
find the contents. However, these six relation-
patients requiring significantly more time to
ships were not significant, although their corre-
find the information (P = 0.006).
lation coefficients were between 0.509 and
A high correlation was also found in the mod-
el versions between locatability and the amount
Furthermore, significantly more participants
of text. However, this was not significant.
stated that the information was easy to locate if:
Furthermore, there was no general relation-
• They needed less time to locate the requested in-
ship between the comprehensibility and the
amount of text; long texts, such as from the
• They found more of the 15 tested key messages
ibuprofen original, were also well comprehend-
In addition, relationships in the group of the
With the exception of the amount of text, the
originals were found as follows. The locatability
correlation coefficients concerning the com-
of the tested key messages decreased in relation
prehensibility of the 15 tested key messages
were always less than 0.5. Significant correla-tions between comprehensibility and partici-
• Nonquantifiable phrases per total number of
pant opinions were not found in either package
words. Words such as “longtime use” are nonquan-
tifiable phrases. They do not enable the reader to
Further significant relationships were found
clearly rate the importance of the information be-ing communicated. For example, “longtime use”
concerning the amount of text to the following
could be interpreted as either a period lasting at
8 of the 17 participant opinions about the
least 1 month or a period lasting up to 1 year or
package inserts. An increase in the number of
• Difficult words per total number of words.
• First impression of the originals deterred the par-
• Sentences longer than 20 words per total number
ticipants from reading further (originals: P = 0.021;
These findings were valid for the percentage of
• Confidence about using the medicine decreased
located information and for the time needed to
(models: P = 0.022; Figure 5). Relationship between theamount of text in packageinserts and the percentageof incorrectly compre-hended information from
Percentage of Incorrectly Comprehended Information
Relationship between theamount of text in packageinserts and the motivationto read the package insert(17). Definitions as in
• Participants felt worse informed by the informa-
much information (originals: P = 0.033, models:
tion contained in the package inserts (originals:
• Information provided in the package insert was
• Participants more frequently did not want similar
more frequently difficult to locate (originals: P =
package inserts in future (originals: P = 0.015).
• Participants more frequently expressed the
• Information provided was difficult to understand
opinion that the package inserts contained too
Relationship between theamount of text in packageinserts and the confidenceto use the medicine afterreading the package insert. Definitions as in Figure 1.
Confidence in the Medicine After Reading the Package Insert
• Participants more frequently stated the text was
The following further relationships concern-
difficult to read (originals: P = 0.032).
ing the participants’ opinions were detected inthe group of the originals:
A similar high number in significant relation-ships of participants’ opinions about the origi-
• An increase of the average number of words per
nals was found in the percentage of difficult
sentence reduced confidence in using the medi-
words per total number of words. Terms were as-
• The higher the percentage of sentences with sub-
sessed as potentially difficult for patients based
junctive tenses, the more people stated, after read-
on both the experience of the study leader and
ing the package insert, that the first impression put
their occurrence in medical dictionaries. The
them off reading the information (P = 0.005), the
higher the percentage of medical terms, the
package insert contained too much information (P
= 0.049), and the important information was notprovided at the beginning (P = 0.01).
• They lost confidence in using the medicine (P =
• The increase in the percentage of words in brackets
per total number of words led to more patients
• The package insert did not explain all important
feeling worse informed about the medicine (P =
0.038); more people stated that the package insert
• The package insert contained too much informa-
contained too much information (P = 0.019); fewer
participants wanted the package insert in the fu-
• The package insert was difficult to understand (P =
ture (P = 0.02); and the information provided was
more difficult to locate (P = 0.043) and to read (P =
• Complicated sentences were contained (P = 0.017).
• Difficult words were in the package insert (P =
• The higher the percentage of words longer than 20
letters, the more participants stated that the text
• The information provided was not precise (P =
was difficult to understand (P = 0.042).
• At the beginning of the package insert there was
Significant influences of demographic data
less important information (P = 0.042).
on the participants’ opinions were often found
(P ≤ 0.005). However, the Cramer V was never
in the year 2000 found an average text amount
over 0.195, which showed that only very weak
of 1,496 words (12). The unpublished PAINT2
relationships exist. The most significant de-
survey of 271 package inserts, randomly select-
pendencies within the 17 investigated opinions
ed from all versions available on the German
were found in the aspect of age (originals 15×,
medicine market in 2005, showed a significant
models 14×) followed by education level (origi-
text increase over 5 years to an average of 2,004
nals 14×, models 11×), sex (originals 5×, models
words per leaflet. Further, rises in the amount of
12×), participant’s mood (originals 8×, models
text are expected, for example, due to the new
10×), and finally, the medicine use (originals 2×,
demands of Directive 2004/27/EC (1), the text
increase of the QRD-template (a text frame for
package inserts in the European Union) (14)
showed that an increase in age led to higher
and continuing practical experiences with the
motivation to read the information. This was
significant in 9 of the 10 investigated package
inserts (P ≤ 0.029). However, the older the par-
FDA, to provide a summary of the most impor-
ticipants, the more frequently the opinion was
tant contents at the beginning of package in-
stated for every original that too much informa-
serts would cause a further increase in the vol-
tion was contained (P ≤ 0.029).
ume of text (15). However, the results of the fivemodel package inserts showed that shorter leaf-
lets without this summary are appropriate to in-
Apart from the number of difficult words con-
form patients about the medicines, so the FDA
tained in package inserts, the amount of text is
also a very important key factor in the use of
pean package inserts. It follows that the current
package inserts. Even if extensive package in-
serts are not generally less comprehensible,
2001/83/EC to require a summary of the essen-
they significantly reduce the possibilities of
tial package insert information (16) similar to
locating the information and patients more
the FDA requirements must therefore be as-
sessed as inappropriate. In addition, no evi-
shorter versions. In addition, long texts de-
dence-based research is available to suggest
crease the motivation to read the provided
that such a summary, as used in the United
contents and in the end only a few people will
States to inform health professionals, is helpful
for patients when included in European pack-
Furthermore, patients who have less trust in
age inserts. This is particularly the case as other
their medicines caused by extensive texts will
layout and design aspects, such as bold print,
more frequently not comply with the instruc-
were successfully used in each of the five mod-
tions. In the worst case they will not use the pre-
els to emphasize the most important informa-
scribed medicines. More significant influences
tion. Apart from the negative effects of increas-
of the amount of text on the use of package in-
ing the amount of text, a summary could more
serts as described in the results are anticipated
frequently lead to patients not reading the en-
as only two different leaflet types, each with five
versions, were investigated in this survey.
The serious negative effects of extensive pack-
In a readability test study with 40 people,
age inserts should be more considered in future
Dickinson et al. (13) also found problems as a
approaches. Therefore, shortening package in-
result of long package inserts. Therefore some
serts is an important aspect to consider. A first
of the participants recommended shortening of
step would be to undertake measures that we
can immediately put into practice before or
An investigation of 68 German package in-
during the package insert user tests. Examples
serts from frequently used medicines selected
• Avoiding repetitions and extensive explanations
In addition, the guidelines, templates, and di-
• Using short points instead of long sentences
rectives should focus more on the essential as-
• Reducing the text that is intended only for doctors
pects. Here there are parallels to package in-serts as precise, comprehensible, concise, and
G U I D E L I N E S , T E M P L A T E S , A N D
realistic rules can be better put into practice. If
D I R E C T I V E I M P R O V E M E N T S
more people understand our guidelines and
The second step is related to ongoing guideline,
templates, this will help us to move forward.
template, and directive optimizations, as user
Guidelines, templates, and directives should
tests alone cannot always reduce the text to the
more closely reflect scientific and practical ex-
optimal amount of fewer than 1,000 words or a
perience. Data relating to the amount of text
were already provided above. However, apply-
One possibility for optimization concerns the
ing the more frequent research results in these
existing Quality Review of Documents (QRD)
documents will avoid unrealistic recommenda-
template, which contains over 500 words (14).
tions such as the recent proposal for amending
The results of this survey with the five model
package inserts, containing a template text of
amended text in package inserts shall, for a pe-
around 200 words, indicate that shorter tem-
riod of 1 year, be presented in bold, with an ex-
plates are sufficient and lead to significantly
tra symbol and the words “New information”
better results in the locatability of information.
(16). Reasons for the impracticability of this
Furthermore, consistency between different
guidelines, templates, and directives would behelpful. However, some documents lack this
• Many medicines have a shelf life of up to 5 years.
Patients receiving medicines shortly before the
consistency, with the result that less appropri-
shelf life ends would have information presented as
ate texts are used in package inserts. For exam-
new that would in fact be old. In addition, patients
ple, the QRD template contains long sentences,
could be confused when text is emphasized in one
repetitions, and abbreviations while both the
package insert as new, not emphasized in the next
old and new readability guidelines recommend
package insert, then in a later package insert again
A further aspect that should be reconsidered
• The use of bold print is very appropriate to empha-
is the requirement to include less important in-
size the most important information. But too fre-
formation. Since the implementation of Direc-
quent use of bold print decreases the effect of em-
medicine is sold in the different European
• The suggested presentation of new information
Union member states have to be provided in
will need an annual update of all package inserts
package inserts (1). However, this information
delivered in the more than 100,000 medicinesavailable in the European Union. This could lead to
is less important for patients (11). Should it be
a collapse of the agencies that have to approve
required by individuals, every pharmacist or
each amendment and increase the costs of the
doctor, and especially the manufacturer, should
be able to provide this information upon re-quest.
guidelines, templates, and directives should be
pharmaceutical company addresses, particular-
provided in fewer documents and preferably on
ly in centralized approved package inserts (14).
one central website so that every person has
No patient sees the need for almost 30 different
easy access to the most up-to-date documents.
addresses of the same company. Therefore, re-
The Regulatory and Procedural Guidance web-
ducing the number of addresses would be an-
site of the EMEA (20) is, in this case, a good op-
other good opportunity to shorten and opti-
portunity for everything that should be consid-
ered in package inserts and user tests to be
provided in one place. If guidelines were pre-
sented in fewer documents, it would avoid con-
fusion. For example, rules relating to user test-
Another aspect is the right time to carry out
ing are provided in the European Commission
user tests. The current situation is that these
document from 2006 (2), in the readability
tests are done before the approval procedure
guideline (19), in national guidelines, and in
starts. However, this can result in text changes
other sources. As a result, discussions were
after the user tests. For example, difficult words
and extensive paragraphs may reoccur in the
and agencies about the actual requirements. A
successfully tested version. One reason is the
similar situation exists in the recommendations
approval procedure. A suggestion is, therefore,
to write easily readable and comprehensible
that the package insert texts are first optimized
and in a second step the pharmaceutical com-panies submit these texts to the agencies for ap-
U S E R T E S T S U C C E S S C R I T E R I A
proval. Afterward, the first test round with pa-tients can start. This recommendation is based
Realistic and appropriate success criteria are
on practical experience, as PAINT-Consult has
also required for the user tests. The current suc-
used it together with some companies in the
cess criterion in the verbal face-to-face inter-
past and it avoided extensive text changes and
view method is the 90/90% rule. In total, a min-
text increase after the test. However, this is only
imum of 80% of the participants should be able
a suggestion to provoke discussion, since gener-
to use each tested key message (2,3,19).
al changes such as this require the existing ap-
The written readability test success criteria
proval procedure to be modified, which is not so
are similar. One such is that in total 80% of the
participants should be able to locate and un-
A further point to take into consideration is
derstand each tested key message. There was a
the harmonization of package inserts in Europe.
discussion relating to higher success criteria.
Professor Sless, one of the verbal interview
successfully tested package insert, but the agen-
method developers, did not recommend higher
cies demand to use another tested version for
user test success criteria than we have at the
harmonization. As a result, the best and shortest
moment because, in his opinion, they are unat-
package insert is not always used. Therefore,
tainable without falsifying the results (21). Fur-
clear rules are required about when a harmo-
thermore, many people have significant reading
nized text should be used or not and specifying
and writing difficulties. For example, 5% of the
that the best and shortest version is to be used.
German adult population have these problems
Otherwise we waste time and resources, and
(22). Therefore, aiming higher than the current
trust will be lost in the current system.
success criteria would not be an appropriateway forward.
Nevertheless, it is necessary to focus on the
User test research shows that ongoing package
improvement of the complete package insert
insert improvements are absolutely necessary.
and not only on the tested information, for ex-
These can be achieved through user testing.
ample, by counting the number of difficult
However, apart from the user test success crite-
words and the amount of text. For this reason,
ria, testing should focus on the improvement
improvements of the entire package insert are
of the entire package inserts. Reducing the
done as the first step of the written readability
amount of text is one very important point. Es-
tests before the first test round with patients
tablishing the right time to carry out user tests
starts. Especially in this step, the main optimiza-
and clear rules for harmonization of the pack-
tions are achieved and the tests with people
age inserts should also be considered.
help to fine-tune the package inserts.
In addition, ongoing guideline, template, and
directive optimizations are essential. These doc-
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The author reports no relevant relationships to disclose.
ABA Guidance for the Responsible Labeling and Marketing of Energy Drinks BACKGROUND AND OBJECTIVE The American Beverage Association (ABA) is the trade association representing the broad spectrum of companies that manufacture and distribute non-alcoholic beverages in the United States. This Guidance relates to the labeling and marketing of energy drinks. Energy drinks are non-alcohol
Ibuprofen foam and silver wound contact layer: A safe combination for treatment of painful, critically colonised leg ulcers Jørgensen, B.1, Gottrup, F.1, Karlsmark, T.1, Sibbald, R.G.2, Bech-Thomsen, N.3 Demographic and baseline measurements 1. Copenhagen. Wound Healing Centre, Bispebjerg University Hospital, Copenhagen, Denmark2. Toronto Wound Healing Centres, University of Toronto, Ont