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Perceptions of generic medication in the
general population, doctors and
pharmacists: a systematic review
Sarah Colgan,
1
Kate Faasse,
1
Leslie R Martin,
2
Melika H Stephens,
1
Andrew Grey,
3
Keith J Petrie
1
To cite: Colgan S, Faasse K,
Martin LR, et al. Perceptions
of generic medication in the
general population, doctors
and pharmacists: a
systematic review. BMJ Open
2015;5:e008915.
doi:10.1136/bmjopen-2015-
008915
▸Prepublication history and
additional material is
available. To view please visit
the journal (http://dx.doi.org/
10.1136/bmjopen-2015-
008915).
Received 27 May 2015
Revised 10 November 2015
Accepted 12 November 2015
1
Department of Psychological
Medicine, University of
Auckland, Auckland, New
Zealand
2
Department of Psychology,
La Sierra University,
Riverside, California, USA
3
Department of Medicine,
University of Auckland,
Auckland, New Zealand
Correspondence to
Professor Keith J Petrie;
kj.petrie@auckland.ac.nz
ABSTRACT
Objective: To investigate negative perceptions about
generic medicines and evaluate the proportions of lay
people, doctors and pharmacists who hold these
perceptions.
Design: A systematic review of observational studies.
Data sources: MEDLINE, EMBASE, PsycInfo and
Scopus.
Eligibility criteria: Quantitative data from cross-
sectional and prospective studies published in English
after 1980, using self-report measures to evaluate
perceptions about generic medicines, presented as
percentages of the total sample assessed.
Results: After screening 2737 articles, 52 articles
were included in the final analysis. A high proportion
of doctors, pharmacists and lay people had negative
perceptions of generics. Lay people were significantly
more likely to view generics as less effective than
branded medication (35.6%, 95% CI 34.8% to 36.4%)
compared to doctors (28.7%, 27.5% to 29.9%) and
pharmacists (23.6%, 21.2% to 26.2%), p<0.0001.
Pharmacists (33.4%, 31.0% to 35.9%) were
significantly more likely to believe generics were of
inferior quality compared to branded medication than
were doctors (28.0%, 26.3% to 29.9%), p=0.0006,
and lay people (25.1%, 24.2% to 26.0%), p<0.0001.
Doctors believed generics caused more side effects
than branded medication (24.4%, 22.2% to 26.9%),
compared to pharmacists (17.6%, 15.3% to 20.1%)
and lay people (18.8%, 17.8% to 19.8%), p<0.0001.
Doctors (28.5%, 26.9% to 30.2%) and pharmacists
(25.4%, 21.4% to 29.9%) had significantly more safety
concerns about generics than did lay people (18.0%,
17.0% to 19.0%), p≤0.0002. A greater proportion of
lay people felt negatively about generic substitution
(34.0%, 33.2% to 34.9%), compared to doctors
(24.1%, 22.0% to 26.4%) and pharmacists (11.0%,
9.6% to 12.7%), p<0.0001. Rates of negative
perceptions of generics do not appear to have changed
substantially over time in the general population or
among physician groups, p≥0.431, but such negative
beliefs show a decreasing trend in pharmacists over
the study period, p=0.034.
Conclusions: A significant proportion of doctors,
pharmacists and lay people hold negative perceptions
of generic medicines. It is likely these attitudes present
barriers to the wider use of generics.
INTRODUCTION
Generic medicines have been available for
many years and are routinely used to treat a
wide range of acute and chronic illnesses. In
order to be approved for use, a generic
medicine must be bioequivalent to the ori-
ginator product, and must be the same in
terms of strength, safety and quality.
1
While
generic medicines are permitted to differ
from their equivalent branded medicine in
terms of colour, size, shape and excipient
ingredients, they must be able to demon-
strate bioequivalence to the originator
product in terms of the rate and extent of
absorption.
23
Generic formulations provide
the same therapeutic effect as branded medi-
cines at a much more economical price.
4
For
this reason, generic drugs have been increas-
ingly popular as a method to reduce pressure
on drug budgets, and they now make up an
increasing percentage of dispensed drugs.
5
Strengths and limitations of this study
▪This review is a comprehensive amalgamation of
current research investigating perceptions of
generic medicines among physicians, pharma-
cists and lay people.
▪Our review used widely accepted methodology to
evaluate the literature, and identified that a sig-
nificant proportion of medical professionals and
lay people hold negative perceptions of generic
medicines.
▪The review may have increased the risk of publi-
cation bias by only including studies that were
published and available through the four data-
bases we accessed, and hand searching was not
performed.
▪While there are a range of studies looking at atti-
tudes of the general population and of doctors
towards generics, there were only nine studies
examining those views of pharmacists, which
may have reduced the accuracy of the estimates
in this group.
Colgan S, et al.BMJ Open 2015;5:e008915. doi:10.1136/bmjopen-2015-008915 1
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Although generic medicine use has become more
widespread, there is evidence that many doctors and
pharmacists hold negative views of generics and resist
prescribing generic medicines.
67
Many doctors oppose
brand substitution, believing generic medicines to be
inferior to their branded counterparts.
7
In the UK,
there was strong opposition when plans were proposed
to introduce generic substitution into UK primary care,
8
as well as controversy about using generic antiepileptic
drugs
9
and generic pregabalin for pain control.
10
A number of surveys have also shown sizable propor-
tions of patients reporting negative views about generics,
believing them to be less effective, of lower quality and
unsuitable for treatment of major illnesses, as compared
to their branded equivalents.
11–14
Such negative views of
generic medicines are important because they are likely
to be associated with poorer health outcomes due to an
association with higher side effect reporting and lower
adherence.
14 15
If a substantial proportion of doctors,
pharmacists and the general population hold negative
views of generic drugs, it could represent an impedi-
ment to the widespread adoption of generic medication.
We conducted a systematic review to examine the atti-
tudes towards generic drugs held by lay people, doctors
and pharmacists. We extracted from the literature the
proportion of participants who held negative views
about how generics were perceived compared to their
branded equivalent for the following five perceptions:
drug effectiveness, drug quality, the likelihood of
causing side effects, drug safety and attitude towards
generic substitution or the process of replacing a
branded medication with its generic equivalent.
METHODS
Inclusion criteria
To be eligible for inclusion in the review, studies had to
include quantitative data presented as proportion of par-
ticipants holding perceptions about generic medicines
along any of the relevant dimensions. Studies could be
either cross-sectional, mixed method or prospective in
design. They also had to be in English, published in or
after 1980, and had to include self-report measures to
evaluate general perceptions about generic medicines,
presented as percentages of the total sample assessed.
Data sources and searches
A systematic search of databases (MEDLINE, EMBASE,
PsycINFO, Scopus) was conducted on 6 September
2015, to retrieve relevant peer reviewed articles. The
search strategy (see online supplementary appendix 1)
employed for this review drew on common phrases and
terms used in the literature concerning generic medi-
cines, and included input from a specialist librarian.
Keywords (appropriately truncated to allow a wide
search) were combined with medical subject headings
(MeSH) to comprehensively search four databases. The
strategy was modified for Scopus due to a different
search platform. Hand searching was not performed,
but reference lists of identified systematic reviews and
narrative reviews were reviewed to identify further
studies.
Data collection
One author (SC) reviewed the titles and available
abstracts for all identified citations, to determine rele-
vance. Following the initial review, two of the authors
(SC and MHS) independently reviewed full-text publica-
tions to make a final selection of included studies.
A structured Excel spreadsheet was used to record rele-
vant information and ensure uniformity of evaluation
for each study. Extracted data included study character-
istics including country of origin, sample type (doctor,
pharmacist or lay population), sample size and propor-
tions of participants with negative perceptions of generic
medicines. The primary outcomes of this review were
the proportions of participants reporting perceptions
about generic medicines in terms of generic substitu-
tion, effectiveness, quality, side effects and safety.
Quality assessment
Two reviewers (KF and LRM) independently examined
the full-text publications to complete a quality assess-
ment. Raters independently categorised the articles as
high, acceptable or poor quality, based on an evaluation
of study design, participants (N, and type), demograph-
ics, recruitment method (random or other), exclusion-
ary criteria, method of assessing perceptions (interview,
questionnaire) and question quality (clarity, appropriate
response options) (see online supplementary appendix 2).
Consensus between the two reviewers was used to resolve
any disagreement. Studies that were classified as being
of poor quality were subsequently excluded. In line with
Cochrane recommendations, we chose not to use a stan-
dardised scoring system to assess study quality.
Calculating a summary score was not carried out so as to
avoid assigning ‘weights’to items on the scale that were
unlikely to accurately reflect their relevance and that
may have changed across different studies.
16
Statistical analyses
From the full text of each paper, the total number of
participants who took part in each study and the per-
centage who held perceptions of generic medicines
across the five domains were extracted. These data were
used to calculate the proportion of participants who
reported negative views of generics compared to those
who reported more accurate or positive views. These
figures were summed to yield a total proportion of nega-
tive to neutral/positive views for each of the three popu-
lation samples under investigation (general population,
physician and pharmacist) for perceptions of effective-
ness, quality, side effects, safety and substitution of
generic medicines. Within each perception, the propor-
tion of negative to neutral perceptions was compared
across the three participant groups using χ
2
tests of
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contingency tables with a Yates correction using
GraphPad QuickCalcs software (http://graphpad.com/
quickcalcs/). As this approach required multiple compari-
sons, a conservative Bonferroni correction with an
adjusted αlevel of p=0.0033 (0.05/15 tests) was used.
For additional clarity and ease of interpretation in the
presentation of the results, the extracted data were also
used to calculate a weighted percentage (equivalent to
the number of participants reporting negative views of
generics out of the total number of respondents in each
sample for each perception) of people holding negative
perceptions across the relevant studies in each domain,
assessed by generating a total sum of the number of par-
ticipants with negative views, and calculating a percent-
age based on the total number of respondents in each
group. Following this, modified Wald 95% CIs were cal-
culated for each weighted percentage value.
17
The
weighted percentages and 95% CIs were calculated
using Microsoft Excel 2010 software.
Finally, Spearman’s correlations were utilised in order to
assess whether there had been a systematic change in per-
ceptions of generic medicines over time. Correlations
between publication year and the percentage of partici-
pants reporting negative perceptions were conducted to
assess relationships between (1) the percentage of partici-
pants holding negative perceptions (across all participants
and all five domains) and publication year, (2) the per-
centage of negative perceptions in each domain (across all
participants) and publication year and (3) the percentage
of negative perceptions across all domains within each of
the three participant groups. Spearman’s correlations
were used because publication year was not normally dis-
tributed (almost 80% of the papers were published in the
past 10 years), and were carried out using SPSS V.22 soft-
ware. As this approach required multiple comparisons, a
conservative Bonferroni correction with an adjusted α
level of p=0.0055 (0.05/9 tests) was used.
RESULTS
Search results
The systematic search process identified 2737 potentially
relevant publications. The initial review eliminated 2582
of these publications, including duplicates, leaving 155
articles for full-text review. Of these, 73 articles were put
forward for quality assessment. During this process, 21
studies were eliminated (figure 1). The publication
dates for these studies ranged from 1987 through 2015,
and included data from 27 countries. Additional
characteristics of the studies included in the review are
presented in table 1 for the general population, and in
table 2 for doctors and pharmacists.
Study quality
The two raters initially made identical assessments in 48
of the 58 eligible papers, yielding a Cohen’sκinter-rater
reliability of 0.70, p<0.001, which indicates substantial
agreement.
18
Subsequently, each of the 10 cases on
which raters disagreed was re-evaluated. For these
studies, one rater had indicated acceptable and the
other, either high or poor quality, but in no case was
there a high–poor pairing. Discussion of rationale for
the non-identical ratings was completed, and the raters
came to a final agreement on each of the 10 cases. Of
58 studies, 29 were classified as high-quality, 23 were clas-
sified as acceptable and 6 were rated as being of poor
quality. The six studies rated as poor quality were
removed from the analysis.
PERCEPTIONS OF GENERIC MEDICINES
Effectiveness
A significantly greater proportion of the general popula-
tion held the view that generic drugs were less effective
than their brand name equivalents (5274/14 817;
35.59% (95% CI (34.83% to 36.37%)), compared to
doctors (1450/5056; 28.68% (95% CI (27.45% to
29.94%)), χ
2
(1)=80.22, p<0.0001) and pharmacists
(264/1119; 23.60% (95% CI (21.20% to 26.18%)), χ
2
(1)=65.57, p<0.0001). The proportion of physicians who
held these negative views was significantly greater than
pharmacists, χ
2
(1)=11.57, p=0.0007 (see figure 2 for
graphical representation of results).
Quality
At least 25% from each group reported the belief that
the quality of generic medications is lower than that of
branded drugs. Pharmacists reported the highest
Figure 1 Flow chart of studies assessing perceptions of
generics.
Colgan S, et al.BMJ Open 2015;5:e008915. doi:10.1136/bmjopen-2015-008915 3
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Table 1 Selected studies assessing layperson perceptions of generic medicines
Authors, date Country Sample N Substitution, % Effectiveness, % Quality, % Side effects, % Safety
Al-Gedadi et al, 2008
21
Malaysia Lay 396 38.80 38.90 31.20
Babar et al, 2011
5
New Zealand Lay 441 22.90 34.20
Bertoldi et al, 2005
23
Brazil Lay 3182 30
Bradley et al, 1998
24
UK Lay 2276 43.90
Costa-Font et al, 2014
25
Spain Lay 2244 13.20
Dunne et al, 2014
26
Ireland Lay 42 18 24 5
Figueiras et al, 2009
27
Portugal Lay 819 40
Heikkilä et al, 2011
28
Finland Lay 1844 19.10 15.50
Himmel et al, 2005
13
Germany Lay 804 36.70
Ibrahim et al, 2012
29
Australia Lay 503 13 13 5 15
Iosifescu et al, 2008
30
USA Lay 315 15.60 11.60 20.10
Keenum et al, 2012
31
USA Lay 172 23.30 13.40
Kobayashi et al, 2011
32
Japan Lay 1215 46
Kohli and Buller, 2013
33
USA Lay 160 17 28 9
Lebanova et al, 2012
34
Bulgaria Lay 216 94 94 94
Lira et al, 2014
35
Brazil Lay 278 20.9 14.4
Nardi et al, 2015
36
Brazil Lay 5000 30.4
Omojasola et al, 2012
37
USA Lay 525 6 7 29.60 3
Palagyi and Lassanova, 2008
38
Slovakia Lay 1777 64 16.70
Perri et al, 1990
39
USA Lay 326 13.50 11.40 6.70
Piette et al, 2010
40
USA Lay 806 31.60 28.50
Rathe et al, 2013
41
Denmark Lay 2476 14.50
Sansgiry and Bhosle, 2004
42
USA Lay 505 10.92 7.40 5.08 6.08
Shrank et al, 2009
43
USA Lay 1047 26.10 9.50
Sicras-Mainar and Navarro-Artieda, 2012
44
Spain Lay (and physician) 203 33.20 42.30
Wong et al, 2014
45
Malaysia Lay 202 23.8 23.3 23.8
Yousefi et al, 2015
46
Iran Lay 1309 81 86 21.4
N reporting negative perceptions 3874 5274 2290 1054 942
Total N sampled 11 386 14 817 9119 5618 5242
Overall percentage 34.03 35.59 25.11 18.76 17.97
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Table 2 Selected studies assessing physician and pharmacist perceptions of generic medicines
Authors, date Country Sample N Substitution, % Effectiveness, % Quality, %
Side
effects, % Safety, %
Andersson et al, 2006
47
Sweden Physicians 892 16.70
Bower and Burkett, 1987
48
USA Physicians 317 37.50
Brust et al, 1990
49
USA Physicians 145 45
Chua et al, 2010
50
Malaysia Physicians 87 33 41.40 52.90
Dosedel et al, 2014
51
Czech
Republic
Physicians 263 39.1 46 37.3
Dunne et al, 2014
52
Ireland Physicians 34 11.8 8.8 11.8
Fabiano et al, 2012
53
Italy Physicians 303 17.50 17.80
Friedman et al, 1987
54
USA Physicians 245 43.20
Gossell-Williams, 2007
55
Jamaica Physicians 60 13 60
Jamshed et al, 2012
56
Pakistan Physicians 206 24.30 39.30 26.70 41.26
Kersnik and Peklar, 2006
57
Slovenia Physicians 117 11.10
Kumar et al, 2015
58
Malaysia Physicians 263 51.7 19.8
Lewek et al, 2014
59
Poland Physicians 170 28.8 12.1
Shrank et al, 2011
7
USA Physicians 506 23.50 50
Sicras-Mainar and Navarro-Artieda, 2012
44
Spain Physician (and
lay)
201 40.80
Theodorou et al, 2009
60
Greece Physicians 1204 14.09 16.83 15.37
Cyprus 193 5.70 7.25 5.70
Tsiantou et al, 2009
61
Greece Physicians 1204 40.70 41.90
N reporting negative perceptions 341 1450 675 316 836
Total N sampled 1414 5056 2406 1292 2928
Overall percentage 24.11 28.68 28.04 24.43 28.54
Allenet and Barry, 2003
62
France Pharmacists 1000 10
Auta et al, 2014
63
Nigeria Pharmacists 154 7.10 54.50
Awaisu et al, 2014
64
Qatar Pharmacists 108 27.70
Babar et al, 2011
5
New Zealand Pharmacists 360 10.60 50 65 28
Chong et al, 2010
65
Australia Pharmacists 157 13.40
Chong et al, 2011
6
Malaysia Pharmacists 219 21.40 38.40
Dunne et al, 2014
66
Ireland Pharmacists 44 2.3 2.3 4.5
Gupta, 1996
67
USA Pharmacists 100 40
Maly et al, 2013
68
Czech Rep Pharmacists 615 7 16.10 11.20
N reporting negative perceptions 179 264 465 174 103
Total N sampled 1622 1119 1392 991 404
Overall percentage 11.04 23.60 33.39 17.56 25.44
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proportion of negative perceptions about quality (465/
1392; 33.39% (95% CI (30.96% to 35.91%)), a signifi-
cantly greater proportion of negative perceptions than
in either the physician sample (625/2406; 28.04% (95%
CI (26.28% to 29.87%)), χ
2
(1)=11.76, p=0.0006) or the
general population (2290/9119; 25.11% (95% CI
(24.23% to 26.01%)), χ
2
(1)=42.51, p<0.0001).
Physicians and general population participants did not
differ significantly from one another (after applying the
Bonferroni correction), χ
2
(1)=8.47, p=0.0036.
Safety
A greater proportion of doctors (836/2928, 28.54%,
95% CI (26.93% to 30.20%)) and pharmacists (103/
404; 25.44%, 95% CI (21.43% to 29.91%)) held the per-
ception that generic medicines were less safe to use than
branded drugs than did the general population (942/
5242; 17.97%, 95% CI (16.96% to 19.04%)), χ
2
(1)
=122.93 and 13.59, respectively, p<0.0001 and 0.0002.
Physicians and pharmacists did not differ from one
another with regard to negative perceptions of safety of
generic drugs, χ
2
(1)=1.49, p=0.22.
Side effects
Physicians were the most likely to hold negative beliefs
that side effects are more frequently caused by generic
drugs in comparison to brand name alternatives, with
one in four (316/1292; 24.43%, 95% CI (22.17% to
26.85%)) endorsing these views. Physicians held signifi-
cantly more inaccurate beliefs about side effects than
did the general population groups (1054/5618; 18.76%,
95% CI (17.76% to 19.80%)), χ
2
(1)=21.09, p<0.0001,
and pharmacists (174/991; 17.56% (95% CI (15.31% to
20.06%)), χ
2
(1)=15.43, p<0.0001. There was no signifi-
cant difference between the proportions of members of
the general population and pharmacists reporting the
perception that the side effects of generic drugs are
higher than branded, χ
2
(1)=0.73, p=0.3934.
Drug substitution
Pharmacists had the lowest rates of negative perceptions
about substitution of generic drugs for their brand
name alternatives (179/1622; 11.04%, 95% CI (9.60% to
12.66%)). The general population were most likely to
report unfavourable attitudes towards substituting a
branded medication with its generic equivalent (3874/
11 386; 34.03%, 95% CI (33.16% to 34.90%)), followed
by physicians (341/1414; 24.11%, 95% CI (21.95% to
26.41%)). Pharmacists had significantly lower rates of
negative perceptions about generic drug substitution
than both, members of the general population and
doctors, χ
2
(1)=348.72 and 90.14, respectively, p<0.0001.
The general population samples held more negative per-
ceptions of drug substitution than did physicians, χ
2
(1)
=55.46, p<0.0001.
Perceptions of generic medicines over time
There was no significant overall relationship between
publication year and the percentage of participants
reporting negative perceptions of generic medicines
across all participant groups and perception domains,
r=−0.04, n=115, p=0.641. Similarly, the percentage of
negative perceptions held across the five domains did
not demonstrate a significant correlation with publica-
tion year for beliefs about effectiveness, r=−0.03, n=37,
p=0.853; quality, r=−0.02, n=25, p=0.919; safety, r=−0.20,
n=18, p=0.424; side effects, r=0.08, n=20, p=0.742; or
appropriateness of substitution, r=−0.11, n=15, p=0.693.
Finally, the change in the percentage of negative percep-
tions over time was assessed separately across the three
participant groups. There was no significant correlation
between negative perceptions and publication year for
Figure 2 Bar graph showing the
percentage (95% CI) of
participants (general population,
physicians and pharmacists)
reporting negative perceptions
across the domains of
effectiveness, quality, safety, side
effects and substitution.
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general population samples, r=0.10, n=60, p=0.431; or
physicians, r=−0.04, n=37, p=0.794. There was a trend
(after applying the Bonferroni correction) towards a sig-
nificant correlation in pharmacists’overall negative per-
ceptions and publication year, r=−0.50, n=18, p=0.034.
Although the result is not statistically significant, it indi-
cates a possible reduction in overall reported negative
perceptions in pharmacists over time.
DISCUSSION
Key findings
Our systematic review identified that a significant pro-
portion of lay people, doctors and pharmacists hold
negative perceptions of generic medicines, perceiving
generics as less effective, less safe, inferior in quality and
more likely to cause side effects compared to their
branded equivalents. More than a quarter of doctors
and the general population believed that generic drugs
are less effective and of poorer quality than branded
medication. A similar proportion of doctors and phar-
macists had safety concerns about generics. While we
did not identify any reduction in negative views of gener-
ics in doctors or lay people over the course of the review
period, there was some evidence that the percentage of
negative views of pharmacists had decreased.
These findings are important, as previous work has
suggested that negative perceptions about generic medi-
cines are major barriers to their acceptance and wide-
spread usage.
2
Furthermore, these findings have
important implications for clinical practice, as pharma-
cists and medical practitioners are in a position where
they can easily transmit their expectations about the
effectiveness and side effects of generic medication to
the patients under their care.
19 20
Research suggests that
the majority of consumers learn about generic medi-
cines from a physician or pharmacist, and this medical
advice is critical to consumers’decision to take a
generic medication.
11 21
Implications
Generic medicines provide cost-effective alternatives to
branded medicines, resulting in considerable savings to
healthcare budgets. However, if consumers are poorly
informed about their equivalence to branded medica-
tion, it is highly unlikely that generic medicines will be
preferred over their branded equivalents.
22
This review
has identified that a significant proportion of health pro-
fessionals and consumers have negative perceptions of
generic medicines. There is clearly a need for interven-
tions aimed at the general population and health profes-
sionals to target misperceptions of inferior quality, safety
and efficacy—as well as to explain the reasons why
generic medicines are cheaper than brand-name equiva-
lents, the meaning of bioequivalence, and the testing
and regulatory processes involved in approving a generic
medicine for general use.
2
Currently, there is a lack of
research regarding what type of intervention may be
effective in improving perceptions of generic medicines.
Strengths and limitations
This review is a comprehensive amalgamation of current
research investigating perceptions of generic medicines
among physicians, pharmacists and laypeople. The
methods used to search and evaluate the literature are
widely accepted. However, it is important to note that we
may have increased the risk of publication bias by only
including studies that were published and available
through one of the four databases we accessed, and
hand searching was not performed. In addition, we only
reviewed studies that were published in English and we
did not include qualitative studies, as we needed to
compute the proportion of participant between physi-
cians, pharmacists and lay groups. While there are a
range of studies looking at the attitudes of the general
population and doctors towards generics, there were
only nine studies examining the views of pharmacists,
and five of these studies had fewer than 200 participants.
This may have reduced the accuracy of the estimates in
this group.
CONCLUSIONS
These results suggest that there are a significant number
of laypeople, doctors and pharmacists with concerns
about the efficacy, safety and quality of generic medi-
cines. The negative perceptions of doctors and pharma-
cists are likely to be barriers to a wider acceptance of
generics, as health professionals have a strong influence
on patients’decisions to take generic medicine. Further
work is needed on how interventions for medical profes-
sionals and for the public can reduce negative attitudes
about efficacy, safety and side effects, in order to
increase the acceptability of generic prescribing and
substitution.
Twitter Follow Keith Petrie at @KeithPetrie and Leslie Martin at
@LeslieRMartin1
Contributors SC and KJP designed the study. SC and MHS searched the
literature and extracted the data. KF and LRM conducted the quality analysis,
and analysed and interpreted the data. SC, KF and KJP drafted the
manuscript. AG, MHS and LRM contributed to the critical revision of the
manuscript. SC and KJP are the guarantors.
Funding This research was funded by the Auckland Medical Research
Foundation and Pharmac (the New Zealand Government’s Pharmaceutical
Management Agency).
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement No additional data are available.
Open Access This is an Open Access article distributed in accordance with
the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license,
which permits others to distribute, remix, adapt, build upon this work non-
commercially, and license their derivative works on different terms, provided
the original work is properly cited and the use is non-commercial. See: http://
creativecommons.org/licenses/by-nc/4.0/
Colgan S, et al.BMJ Open 2015;5:e008915. doi:10.1136/bmjopen-2015-008915 7
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Colgan S, et al.BMJ Open 2015;5:e008915. doi:10.1136/bmjopen-2015-008915 9
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a systematic review pharmacists:general population, doctors and
Perceptions of generic medication in the
Grey and Keith J Petrie
Sarah Colgan, Kate Faasse, Leslie R Martin, Melika H Stephens, Andrew
doi: 10.1136/bmjopen-2015-008915
2015 5: BMJ Open
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