Advising vaccinations for the elderly: a cross-sectional survey on differences between general practitioners and physician assistants in Germany
Klett-Tammen et al. BMC Family Practice
Advising vaccinations for the elderly: a cross-sectional survey on differences between general practitioners and physician assistants in Germany
Carolina Judith Klett-Tammen 0 2
Gérard Krause 0 1
Thomas von Lengerke 3
Stefanie Castell 0
0 Department for Epidemiology, Helmholtz Centre for Infection Research , Inhoffenstr. 7, Braunschweig 38124 , Germany
1 Chair for Infectious Disease Epidemiology, Hannover Medical School , Hannover , Germany
2 Institute for Epidemiology, Social Medicine and Health Systems Research, Hannover Medical School , Hannover , Germany
3 Medical Psychology Unit, Hannover Medical School , Carl-Neuberg-Str. 1, Hannover 30625 , Germany
Background: In Germany, the coverage of officially recommended vaccinations for the elderly is below a desirable level. It is known that advice provided by General Practitioners and Physician Assistants influences the uptake in patients ≥60 years. Therefore, the predictors of advice-giving behavior by these professions should be investigated to develop recommendations for possible actions for improvement. Methods: We conducted a postal cross-sectional survey on knowledge, attitudes and advice - giving behavior regarding vaccinations in the elderly among General Practitioners and Physician Assistants in 4995 practices in Germany. To find specific predictors, we performed logistic regressions with non-advising on any officially recommended vaccination or on three specific vaccinations as four separate outcomes, first using all participants, then only General Practitioners and lastly only Physician Assistants as our study population. Results: Participants consisted of 774 General Practitioners and 563 Physician Assistants, of whom overall 21 % stated to have not advised an officially recommended vaccination in elderly patients. The most frequent explanation was having forgotten about it. The habit of not counselling on vaccinations at regular intervals was associated with not advising any vaccination (OR: 2.8), influenza vaccination (OR: 2.3), and pneumococcal vaccination (OR: 3.1). While more General Practitioners than Physician Assistants felt sufficiently informed (90 % vs. 79 %, p < 0.001), General Practitioners displayed higher odds to not advise specific vaccinations (ORs: 1.8-2.8). Conclusions: To reduce the high risk of forgetting to advice on vaccinations, we recommend improving and promoting standing recall-systems, encouraging General Practitioners and Physician Assistants to counsel routinely at regular intervals regarding vaccinations, and providing Physician Assistants with better, tailor-made information on official recommendations and their changes.
Vaccination; Elderly; Aged; General practitioners; Physician assistants; Health knowledge; Attitudes; Practice
Recommendations of the German Standing Committee
on Vaccination (STIKO) include influenza vaccination
(IV), tetanus vaccination (TV) and pneumococcal
vaccination (PV) for individuals who are 60 years or older [
These officially recommended vaccinations are financially
compensated by the statutory health insurances [
] as the
benefit risk ratio of the recommended vaccines has been
assessed to be positive [
]. Although general
practitioners (GP) are mostly self-employed and therefore have
to care for the economic aspects of their practice, they
receive an appointed amount for a specific service. As there
are several associations of statutory health insurance
physicians for different regions in Germany and each
negotiates the compensation for the physicians for specific
services with the statutory health insurances, the
specific compensation for vaccinations might differ.
Vaccination coverage for PV in the elderly is as low
as 31 % in Germany [
]; for IV, it is with 37 % clearly
lower than the target of 75 % vaccination in the
], given by the World Health Organization [
while it is high for TV with 93 - 95 % [
GP and physician assistants (PA) advice on
vaccinations, and recommendations by these professions
influence the vaccination uptake especially in the
]. In Germany, PA assist physicians
regarding checkups, treatment, care and counselling of
patients and organizational and administrational
aspects, but do not treat or counsel autonomously. It
can be assumed that in almost every non-private general
practice in Germany, at least one PA works. PA
themselves cannot open a practice and treat patients but only
assist physicians [
]. However, while there is some basic
evidence from the year 2000/2001 regarding knowledge,
attitude, and practice (KAP) factors with respect to
vaccinations in the elderly in German GP [
] and predictors
for advising specific vaccines to individuals in this
agegroup in American [
] and Australian [
PA have been neglected in vaccination-related research in
Germany so far. To our knowledge, there has been no
study analyzing vaccination-related KAP or KAP as
predictors for advice-giving behavior towards the elderly in
GP and PA for TV, IV and PV in a sample representative
for Germany using multivariable analyses. Therefore, we
conducted a survey in both professions in Germany and
explored - within the KAP-framework - predictors for not
giving vaccination advice to the elderly in general, and on TV,
IV, and PV specifically, to gain insight into opportunities for
profession specific improvement of advice-giving behavior.
We developed two KAP-questionnaires (for GP and PA
specifically), and piloted them, using cognitive
pretestinterviews as think-aloud, comprehension, category
selection and information retrieval probing and
confidence rating [
] in 16 persons. We assembled a
database comprising all German GP treating adult patients
with statutory health insurance using publicly accessible
data from the federal associations of statutory health
insurance physicians and the medical councils; and then
selected a random sample of 5000 practices, stratified
and weighted for federal state. We mailed two
questionnaires to each selected practice in March 2015. All
questionnaire variables and their definitions are presented in
Additional file 1.
We evaluated the representativeness of our study
population by chi-square tests, using the atlas of
] for age-distribution and location of practice,
i.e. working in East/West Germany with Berlin as East
of GP, the statistics of physicians [
] for sex-distribution
of the physicians, and the statistics of employees in health
] for sex- and age-distribution of PA as data on
the source populations.
We performed logistic regressions for each of the
four outcomes, i.e., reporting not having recommended
any vaccination/TV/IV/PV despite official
STIKOrecommendation and in the absence of
contraindication in the elderly. Each regression was modelled three
times: including all participants, only GP, and only PA,
excluding PA that did report to be not responsible for
vaccination counseling in their practice (n = 107). We
included all variables with p < 0.25 in bivariate analyses
(using chi2 -test for nominal variables, t-test for
normally distributed metric, and Mann-Whitney-U for not
normally distributed metric and ordinal variables, with
the distribution tested graphically and by
ShapiroWilk-test) and applied backward selection with p < 0.2
as model inclusion criteria. If more than 5 % of missing
values in predictor variables occurred, we used
chainmultiple imputations with five datasets for
multivariable analyses. Otherwise and in bivariate analyses, we
conducted complete case analyses. For multivariable
analysis, we used the GP answer for the PA when GP
and PA from the same practice stated to work in
different parts of Germany (n = 272). We report associations
with p < 0.05 as statistically significant. All analyses
were carried out using Stata 12.
Of the netto-sample of 4995 practices, 16.3 % returned
questionnaires (813/4995) corresponding to 13.4 %
eligible participants (1337/9990) (Fig. 1).
Median age of GP was 54 years (interquartile range
(IQR): 48–61), median time working as GP was 17 years
(IQR: 10–24), 47 % of the respondents were female and
77 % worked in the Western part of Germany. Median
age of PA was 43 years (IQR: 30–51), median time
Response on individual level
46,159 GP in database
Response on practice-level
10,000 questionnaires sent out (2 for each surgery)
13.4% (1,337/9,990 questionnaires)
not target group
not target group
GP: 15.5% (774/4,995)
working with a GP was 20 years (IQR: 10–30), and 97 %
of the respondents were female.
Regarding age-distribution, we found no significant
difference between our study population and the
source population for both professions (all p > 0.05);
regarding location of practice, we found no difference
for GP (p > 0.05), while more female GP (47 % vs
43 %, p = 0.02) and more male PA (3 % vs. 2 %, p =
Description of knowledge, attitude, and practices
Of all participants, 265 (22 %) stated to have not advised
at least one vaccination to an elderly patient despite
STIKO-recommendation and absence of a
contraindication. PV was the vaccination most frequently not being
suggested (n = 183), i.e. 15 % of all participants involved
in counseling on vaccinations, or 19 % (148/774) of GP
respectively. Most participants reported to know (92 %,
1235/1337) and to trust (90 %, 1200/1337) the
STIKOrecommendations. Whereas 85 % (1140/1337) of the
respondents felt in general sufficiently informed about
vaccinations in the elderly, 66 % (880/1337) required better
information on changes of STIKO-recommendations.
Respondents supported (95 %, 1265/1337) discussions
about vaccinations being initiated by patients and
utilized this as an opportunity to counsel (92 %, 1232/
1337) (Table 1).
The most common explanations given by
respondents for not advising was for all three investigated
vaccinations forgetting to advise (53–72 %), followed by
the perceived low risk of the patient to catch the
respective disease (23–28 %). Uniquely for IV, 19
participants (14 %) stated to not have advised it due to safety
concerns and 21 (15 %) due to doubts on its
effectiveness (Table 2).
GP and PA:
5,000 practices contacted
16.3% (813/4,995 practices)
Predictors for not advising vaccinations
In multivariable analyses, odds ratios (OR) >1 imply that
the influencing factor increases the chance of not having
advised a vaccination to elderly, while OR <1 signify an
increasing chance that a vaccination is always advised
when medically indicated and recommended by STIKO.
Most prominent predictor for any (4.4, 1.0–19.4) and
tetanus vaccination (4.9, 1.5–16.5) is not trusting the
STIKO-recommendations; although this concerns only
2 % of respondents (25/1337). For influenza (7.8, 3.6–
16.9) and pneumococcal vaccination (3.5, 1.5–8.2), the
negative perceived benefit-harm-ratio of the respective
vaccine showed the most substantial association for not
advising it to the elderly. While working in
WestGermany more than doubles the odds for not advising
any vaccination (2.9, 1.7–4.9), IV (2.4, 1.3–4.5) and PV
(2.8, 1.6–5.1), this association is not significant in the
model for TV. Not counseling on vaccinations at regular
intervals, e.g. at the first visit of a patient within an
accounting period, is associated with not advising any
vaccination (2.8, 1.5–5.3), IV (2.3, 1.1–5.1), and PV (3.1,
1.5–6.7). GP exhibit about two times the odds for not
having advised specific vaccinations compared to PA
(TV: 2.8, 1.5–5.4; IV: 2.6, 1.5–4.6; PV: 1.8, 1.1-3.0) (Fig. 2,
Additional file 2).
Comparison of general practitioners and physician
PA supported GP regarding counseling on vaccinations
in 79 % (612/813) of responding practices. Despite the
higher chance of GP to not have advised all
investigated vaccinations in the elderly compared to PA,
more GP than PA felt sufficiently informed regarding
vaccinations in adults (90 % of GP (696/774) vs. 79 %
of PA (444/563), p < 0.001), stated to know
STIKOrecommendations (97 % of GP (752/774) vs. 86 % of
Not advised at least one recommended vaccination in the
elderly without presence of a contraindicationa
PA (483/563), p < 0.001), and to use them as a source
of information (85 % of GP (662/774) vs. 69 % of PA
(388/563), p < 0.001). For all investigated vaccinations,
less PA than GP believed the benefit to exceed
potential harms (all p < 0.001) (Table 1).
Modelling GP and PA separately indicates that e.g.
location of the practice in the Western part of Germany,
and not counseling routinely at regular intervals
increases the chance for not advising on any vaccination
only in GP, whereas e.g. age-structure of practices’
patients is only a significant predictor in PA (Table 3,
Additional file 3).
Over 20 % of the participants stated that they had not
advised at least one officially recommended vaccination,
even in absence of any specific contraindication; with
26 % of the GP and 14 % of the PA, significantly more
physicians than assistants reported a vaccination-advise
practice deviating from recommendations. By far the
most frequent explanation in both professions was
“having forgotten to advise”. More than 20 % of PA did
not feel sufficiently informed regarding vaccinations in
adults (vs. 10 % of the GP); 90 % of the respondents
stated that they trusted the official
STIKOrecommendations, and very few were general
opponents of vaccination. Only 17 % of the participants
counsel routinely at regular intervals and just 23 % use
a recall-system. In general, the chance of not advising is
higher in practices in West-Germany and with younger
patients. Also, those who do not counsel routinely at
regular intervals, those with a neutral attitude towards
counseling, and who do not trust the
STIKOrecommendations have a higher chance of not advising.
Overall, associations with KAP-variables were rather
similar across different vaccines, while we observed
some significant distinctions between GP and PA. The
high proportion of GP and PA working in the Western
part of Germany can be explained by the general high
proportion of the German population living there (~16
million in the Eastern part versus ~65 million people in
the Western part [
There are only few vaccination-related KAP-surveys
among GP that address vaccinations in the elderly. A
German study, published 16 years ago, found the same
geographic difference in following the official
recommendations as we did, with GP in the Western part of
Germany vaccinating/advising less often than in the east
]. This matches the observation of general higher
vaccination coverage in the Eastern part of Germany [
the 18 % of their respondents never vaccinating against
pneumococci, the 19 % of GP in our study, who reported
that they had not advised PV (mostly due to having
forgotten to do so), seem to be comparable, although the
outcomes are not exactly the same, as we did not ask
about the actual vaccination, but about advising
vaccinations. Opportunities for vaccination were similar to our
study, e.g. a majority of 84 % stated to counsel during
preventive check-ups and 71 % at first contact with a
patient, although, with only 4 %, even less participants
stated to counsel routinely at regular intervals [
association of the perceived benefit-harm-ratio of the
corresponding vaccine with not advising IV and PV
which we saw in our results was matched by the result
of a survey in the USA [
], where mainly belief-related
predictors as perceived vaccine-effectiveness for
advising IV and PV were found. In Australia, most common
explanations for not giving vaccinations to the elderly
by GPs were refusal of patients (88 %) and competing
priorities (35 %) [
]. In a Canadian study, addressing
mainly childhood vaccinations, nurses were also
included, showing a more positive attitude towards
administering different vaccinations during a single visit
than physicians [
], which is in line with the result in
our study that less PA than physicians reported
advicefailures. As the PA in our study did not show a
substantially more positive attitude towards vaccinations, the
lower proportion of reported non-advising than in GP
could demonstrate a more rule-governed behavior of
the PA, a higher vulnerability to a social desirability
bias or less knowledge of norms and therefore less
conscious deviation of these norms.
So far, PA have been neglected in public health
vaccinology in Germany; however, as they also counsel and
administer vaccinations [
], it would be beneficial
to include them in future activities or interventions
regarding vaccine-uptake. Our study has generated new
knowledge concerning the needs for information of PA
and points out attitudes that can be useful to optimize
future interventions. Since our study included
physicians and their assistants, using mostly the same
questions, we were able to compare both professions
systematically with respect to knowledge, attitudes and
practices. Thus, we found statistically significant
differences not only in advice-giving behavior, but also in
subjective knowledge of official recommendations and
the trust they are met with. This also applies to other
aspects like the perceived benefit-harm-ratio of certain
vaccines, and practices like the sources of information
OR and 95%CI
Odds for not advising lower
Odds for not advising increased
Regarding vaccinations, patients should be informed by
self-help/support groups for vaccine-preventable diseases
Not counseling routinely at regular intervals (Ref: Yes)
Not counseling due to travel plans (Ref: Yes)
Not counseling at preventive checkups (Ref: Yes)
Not counseling when indicated by recall-system (Ref: Yes)
Using further training as source of information (Ref: No)
Using professional journals as source of information (Ref: No)
Using a professional association as source of information (Ref: No)
Not advised any vaccination
Not advised tetanus vaccination
Not advised influenza vaccination
Not advised pneumococcal vaccination
Statistically significant (defined as p < 0.05) associations with not advising at least one vaccination in the elderly despite STIKO-recommendations and no contraindication
modelled separately for General Practitioner (GP) and Physician Assistant (PA); non-significant results (p ≥ 0.05) are added if any level of a variable yielded a significant result
and are shown in italics
Ref Reference, SD Socio-demographic and practice-characteristics, P Practice, n.s. not significant
Strengths and limitations
The evaluation of the representativeness regarding age,
sex and location of practice by chi-square tests did not
indicate any bias in recruitment or response within the
German population of GP and PA, despite the low
response with 11.3 % in PA and 15.5 % in GP. Still, the
variables available for investigating representativeness do
not necessarily represent characteristics relevant for the
research question at hand. Furthermore, using other
statistical test methods might result in different findings.
The generalizability of our results is therefore limited.
Due to known difficulties in recruiting GPs for such
studies in Germany [
], we chose not to test the
knowledge regarding vaccinations, in order not to embarrass
and thus repel possible participants. However, we
assume our design, i.e. asking how well subjects feel
informed, to describe this factor sufficiently well. As we
merely assessed self-reported advice-giving behavior, not
actually observing the routine, unintentional
misperceptions by the participants regarding recommendations,
contraindications, or their own behavior, biased
responses might be possible. To avoid bias due to lack of
awareness of the recommendations for TV, IV and PV,
we specifically asked if a vaccination had ever not been
recommended to a person of at least 60 years, despite
the absence of a contraindication. We also provided the
option to state that the participant did not know about
above-mentioned recommendations. Still, due to social
desirability or recall problems an underestimation of not
advising vaccinations by GP and PA is possible.
By far the most frequent explanation given for not
advising a vaccination was forgetting about it, matching the
substantial association of not advising any, influenza and
pneumococcal vaccination with not counseling routinely
at regular intervals. Still, despite improvements in this
field (compared to 2000 [
]), only a minority of
participants stated that they counselled regularly or used a
recall-system. As it is known that many opportunities
for counseling on vaccinations are not used [
easy-to-implement automated recall-feature complying
with legal requirements and integrated in the practice
management system seems to be an absolute necessity
of modern health care administration. Furthermore, it
has to be promoted that these functions exist and how
and under which circumstances they can be used for
reminding patients and alerting GP and PA [
if there are new developments as automated
management of appointments including possibilities for recalls
. In most practices, PA also counsel on vaccination,
but seem to feel insufficiently informed about
vaccinations in adults or changes in STIKO recommendations.
Therefore the provision of better edited information
(e.g. on efficacy and safety), tailored specifically to the
needs of PA might improve the situation significantly.
Another option to improve the vaccination rates in the
elderly could be to allow for other health care specialists
to apply specific vaccinations, as public health services.
In Ireland, pharmacists are involved [
] with good
results for influenza vaccination [
]. However, in
some areas physicians seem to be the most important
source of vaccinations and vaccination counselling .
Empowering PA, installing and promoting mechanisms
to reduce the risk of forgetting to give vaccination advice
and include special vaccination hours in public health
services in the vaccinations procedure may open up new
avenues to improved vaccination coverage in the elderly.
Additional file 1: Variables: definitions and origins. Description: List of
all variables, their definitions and origins. (PDF 239 kb)
Additional file 2: Multivariable analyses of associations with not
advising vaccinations despite STIKO-recommendation. Description: Full
models including non-significant associations with not advising specific
vaccinations. N = 1337. (PDF 466 kb)
Additional file 3: Multivariable analyses of associations with not
advising vaccinations despite STIKO-recommendation in GPs and PAs
separately. Description: Full models including non-significant associations
with not advising specific vaccinations. (PDF 446 kb)
GP, general practitioner; IV, influenza vaccination; P, practice; PA, physician
assistant; PV, pneumococcal vaccination; SD, socio-demographic and
practice-characteristics; STIKO, German standing committee on vaccination;
TV, tetanus vaccination.
Denise Muschik, André Karch, and Nicole Rübsamen provided statistical
support. Helga Brink provided proof-reading.
The authors thank the General Practitioners and Physician Assistants that
participated in the pilot study and in the survey and the experts that gave
advice on the questionnaire.
The study was partly funded by the Ministry of Science and Culture of Lower
Saxony as part of the doctoral program GESA: Health related care for a
selfdetermined life in old age – Theoretical concepts, users’ needs and responsiveness
of the health care system.
Availability of data and materials
The dataset supporting the conclusions of this article is available upon request
at the corresponding author.
SC, GK and CJKT conceived the study; CJKT developed the questionnaire,
conducted the survey, and performed the statistical analyses. SC coordinated
the survey and the analyses and provided comments and consultation on all
aspects of the work. GK provided technical expertise and advice on
conducting the survey and on the interpretation of the data. TvL gave
advice on all stages of the project. CJKT composed the initial manuscript
with contributions from SC; GK and TvL commented. All authors are equally
responsible for the content of the manuscript and have read and approved
the final manuscript.
All authors declare no competing interests.
Consent to publish
Ethics approval and consent to participate
All procedures performed in this study involving human participants were in
accordance with the institutional and national research committee and with
the 1964 Helsinki declaration and its later amendments or comparable
ethical standards. The dataset did not include individual personal data. The
study was approved by the Ethics committee of Hannover Medical School
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