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SchmittJ, etal. BMJ Qual Saf 2022;0:1–9. doi:10.1136/bmjqs-2021-013864 1
ORIGINAL RESEARCH
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Correspondence to
Dr Martin Roessler,
Universitätsklinikum Carl
Gustav Carus, Zentrum
für Evidenzbasierte
Gesundheitsversorgung, 01307
Dresden, Germany;
martin. roessler@ uniklinikum-
dresden. de
JS and MR contributed equally.
JS and MR are joint first authors.
Received 21 June 2021
Accepted 23 March 2022
To cite: SchmittJ, RoesslerM,
ScribaP, etal. BMJ Qual Saf
Epub ahead of print: [please
include Day Month Year].
doi:10.1136/
bmjqs-2021-013864
Effect of clinical peer review on
mortality in patients ventilated for
more than 24 hours: a cluster
randomised controlledtrial
Jochen Schmitt,1 Martin Roessler ,1 Peter Scriba,2 Felix Walther,1,3
Xina Grählert,4 Maria Eberlein- Gonska,3 Ralf Kuhlen,2 Olaf Schoffer 1
© Author(s) (or their
employer(s)) 2022. Re- use
permitted under CC BY- NC. No
commercial re- use. See rights
and permissions. Published by
BMJ.
ABSTRACT
Background Although clinical peer review is a well-
established instrument for improving quality of care,
clinical effectiveness is unclear.
Methods In a pragmatic cluster randomised controlled
trial, we randomly assigned 60 German Initiative
Qualitätsmedizin member hospitals with the highest
mortality rates in ventilated patients in 2016 to
intervention and control groups. The primary outcome
was hospital mortality rate in patients ventilated
fore more than 24 hours. Clinical peer review was
conducted in intervention group hospitals only. We
assessed the impact of clinical peer review on mortality
using a difference- in- difference approach by applying
weighted least squares (WLS) regression to changes in
age- adjusted and sex- adjusted standardised mortality
ratios (SMRs) 1 year before and 1 year after treatment.
Recommendations for improvement from clinical peer
review and hospital survey data were used for impact
and process analysis.
Results We analysed 12 058 and 13 016 patients
ventilated fore more than 24 hours in the intervention
and control hospitals within the 1- year observation
period. In- hospital mortality rates and SMRs were 40.6%
and 1.23 in intervention group and 41.9% and 1.28 in
control group hospitals in the preintervention period,
respectively. The groups showed similar hospital (bed
size, ownership) and patient (age, sex, mortality, main
indications) characteristics. WLS regression did not yield
a significant difference between intervention and control
groups regarding changes in SMRs (estimate=0.04, 95%
CI= −0.05 to 0.13, p=0.38). Mortality remained high
in both groups (intervention: 41.8%, control: 42.1%).
Impact and process analysis indicated few perceived
outcome improvements or implemented process
improvements following the introduction of clinical peer
review.
Conclusions This study did not provide evidence
for reductions in mortality in patients ventilated for
more than 24 hours due to clinical peer review. A
stronger focus on identification of structures and care
processes related to mortality is required to improve the
effectiveness of clinical peer review.
INTRODUCTION
The COVID- 19 pandemic has highlighted
the crucial role of long- term ventilation
in the care of critically ill patients.1 Due
to different life- threatening indications
and the risk of severe complications,2 3
treatment of intensive care patients is a
complex task. Therefore, ensuring a high
quality of care with respect to treatment
Key messages
What is already known on this topic
►Clinical peer review is a well- established
method that aims to improve the quality
of inpatient care and patient outcomes.
While observational studies indicated
decreasing mortality rates in multiple
patient groups after the introduction
of clinical peer review in German
hospitals, there is a lack of high quality
confirmatory evidence.
What this study adds
►We assessed the effect of clinical
peer review on mortality in patients
ventilated for more than 24 hours in a
cluster randomised controlled trial. We
did not find evidence for reductions in
mortality due to clinical peer review.
Impact and process analysis indicated
few perceived outcome improvements
or implemented process improvements
following the introduction of clinical
peer review.
How this study might affect research,
practice and/or policy
►A stronger focus on structures and
care processes related to mortality is
required to improve the effectiveness of
clinical peer review.
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Original research
of those patients is a main objective of intensive care
medicine.
In addition to new medical therapies, structured
ventilation protocols and improved infrastructure,
the organisational aspects of care, interprofessional
collaboration and quality improvement methods
have increasingly been gaining clinical and scientific
interest.4 5 One well- established quality improve-
ment method is clinical peer review (clinical PR).6–8
In Germany, Initiative Qualitätsmedizin (IQM) hospi-
tals introduced clinical PR in 2009. Within 10 years
(2009–2019), 1208 clinical PRs were performed. With
more than 400 member hospitals, IQM covers approx-
imately 40% of all German hospital cases per year.9
Clinical PRs may be triggered by quality indicator
results (eg, above- average mortality rates in specific
patient groups) and by the voluntary participation of
member hospitals.
Observational studies indicated decreasing mortality
rates after the introduction of clinical PR.10–12
However, these findings may be driven by phenomena
like regression to the mean bias,13 which implies the
need for high quality confirmatory evidence on the
effectiveness of clinical PR.14
Against that background, we conducted a pragmatic
cluster randomized controlled trial to assess the effec-
tiveness of clinical PR in reducing hospital mortality in
patients ventilated for more than 24 hours.
METHODS
Trial design and oversight
This was a pragmatic multicentre cluster randomised
controlled trial embedded in a prospective cohort
study (figure 1). All 385 IQM member hospitals in
Germany were invited to participate in the study. After
consent, 60 participating hospitals with the highest
mortality rates in patients ventilated for more than 24
hours in 2016 were included in the cluster trial as these
hospitals were expected to show the highest potential
for benefit from clinical PR. All remaining hospitals
formed a parallel observation arm. The 60 hospitals
included in the trial were randomised into interven-
tion and control groups with an allocation ratio of
1:1. Clinical PR was conducted in intervention group
hospitals, and control group hospitals did not receive
this intervention. The effectiveness of clinical PR was
assessed by comparing intervention and control group
hospitals regarding changes in the primary outcome 1
year before and 1 year after clinical PR. The interven-
tion was introduced in the second half of 2017.15
While the exact pretreatment and post- treatment
periods were defined by the clinical PR date for inter-
vention group hospitals, these periods were set from
July 2016 to June 2017, and July 2017 to June 2018
for all control group hospitals.
Patient characteristics were gathered from routine
care data collected by each hospital according
to German law (§21 Krankenhausentgeltgesetz
(KHEntgG)). Hospital characteristics were derived
from the German Hospital Directory provided by
the German Federal Office of Statistics. Data linkage
and anonymisation was conducted by the Koordi-
nierungszentrum für Klinische Studien, Technische
Universität Dresden (TU Dresden). Data were analysed
at the Center for Evidence- Based Healthcare (ZEGV),
TU Dresden. The responsible statistician was blinded
throughout the trial conduct and analysis.
For impact and process analysis, we extracted
information from the lists of recommendations for
improvement made by the clinical PR teams visiting
the intervention group hospitals and conducted a
hospital survey at the end of the study period (January
2019 to June 2019). The study design is described in
detail elsewhere.16
Randomisation
We allocated the 60 intervention study hospitals to
intervention and control groups using block rando-
misation conditional on hospital ownership (public,
private, non- profit) and the number of hospital beds
Figure 1 Design of the ‘Effectiveness of the IQM peer review procedure to improve in- patient care—a pragmatic cluster randomized controlled trial’
(IMPRESS) study. IQM, Initiative Qualitätsmedizin.
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(1–149, 150–299, 300–599, 600+) with a block size
of 10. Randomisation was conducted at ZEGV. IQM
was responsible for the enrolment and assignment of
hospitals to intervention and control groups.
Intervention
The IQM clinical PR intervention includes three
stages: preparation, implementation and follow- up
(a more detailed description of IQM clinical PR is
provided in the online supplemental material). The
preparation stage includes patient case selection and
a self- assessment by the hospital selected for clinical
PR. The key element of the implementation stage
is the external, on- site assessment. This assessment
includes structured dialogue between reviewers and
hospital staff with the objective to agree on meas-
ures for improvement of care. The main element of
the follow- up stage is the reviewer report. This report
considers the following criteria:
►Adequate and prompt diagnostics and treatment.
►Prompt and targeted examination of treatment process.
►Adequate and prompt indication.
►Guideline adherence.
►Control of the course of treatment.
►Conflict- free interdisciplinary and interprofessional
cooperation.
►Coherent and complete documentation.
By focusing on these criteria, the intervention
aims to improve inpatient care through an improve-
ment of key structures and processes. Measures for
improvement are mutually defined by staff of the
visited hospitals and clinical PR reviewers and trans-
ferred into a feasible action plan by the reviewed
hospital. Clear and precise formulation of poten-
tials for improvement to derive this action plan is
the main focus of the clinical PR report. The visited
hospital is responsible for both the action plan and
its implementation.
Our study followed the IQM methodology and
conducted clinical PRs in line with international stan-
dards. The clinical PR included the ex- post review of
12–16 charts of patients who were ventilated for more
than 24 hours and deceased in the reviewed hospital.
Preference was given to deceased patients with charac-
teristics that are associated with a relatively low prob-
ability of death (eg, younger age). The reviews were
conducted by physicians and nurses from other IQM
member hospitals, who had been trained in clinical
PR. The training placed special emphasis on avoiding
sham peer reviews.8 Potentials for improvement
identified by the clinical PR team and recommended
measures were discussed with the clinical management
of the reviewed hospital and documented in a list of
recommendations. Based on these recommendations,
reviewed hospitals decided on implementation of
specific measures (see online supplemental figure S1
for visualisation of the process).
Outcome
The outcome of the intervention study was in- hos-
pital mortality in patients ventilated for more than
24 hours, excluding newborns aged ≤27 days. This
outcome was chosen because of its high prevalence
and large reductions in mortality in ventilation
patients after clinical PR found in previous observa-
tional studies.10–12 Subgroup analyses were conducted
for patients ventilated for more than 24 hours with
myocardial infarction, stroke, pneumonia, chronic
obstructive pulmonary disease (COPD) and colorectal
resection because of their relatively large share in total
ventilation patients and their higher degree of homoge-
neity compared with the overall patient population.16
The definitions of patient population and subgroups
followed the German Inpatient Quality Indicators
version 5.017 (indicator 56.1) (see online supplemental
table S1).
Impact and process analysis
To gain insights into measures, processes and perceived
outcomes during and after clinical PR, we extracted
information from the intervention group hospitals’
lists of recommendations for improvement. These
lists of recommendations were written by the leading
reviewer and sent to intervention hospitals for their
information. Information on documented potentials
for improvement and recommended measures was
included in an individualised hospital survey. All inter-
vention group hospitals were invited to participate in
this survey. In this way, we assessed whether specific
measures recommended during the clinical PR process
had been implemented in the relevant hospital. We also
assessed perceived changes in structure, process and
outcome due to clinical PR. The survey was conducted
online using REDCap (V.8.5.8, Vanderbilt University,
Nashville). Descriptive quantitative analysis of survey
data was performed using SPSS (V.25.0.0.2). Qualita-
tive analysis was conducted by two independent raters
using MAXQDA (V.11.1.2) coding qualitative contents
into iteratively defined subthemes. Both raters inde-
pendently rated a sample of 10 questionnaires to
define a common coding framework. After discussion
and consensus, we applied this coding framework to
all questionnaires.
In addition to implementation of measures recom-
mended during clinical PR, the potential of these
measures to affect mortality is a requisite for outcome
improvements. The mortality relevance of the
measures extracted from the lists of recommendations
for improvement therefore was independently rated by
four clinical experts. Each expert received the full list
of recommended measures documented in the inter-
vention study hospitals’ lists of recommendations for
improvement and was asked to rate the mortality rele-
vance of these measures on a 4- point scale (1: almost
surely relevant; 2: likely relevant; 3: likely irrelevant;
4: almost surely irrelevant). The median rating by the
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Original research
experts was used to assess the potential effectiveness
of the intervention and to explain potentially hetero-
geneous or null results of the treatment effect analysis.
Details on this expert rating and the hospital survey
are provided in the online supplemental material.
Statistical analysis
Power simulation was conducted before the start of the
study. Given a significance level of 5% and assuming
30 hospitals per study group, an expected number of
300 ventilation cases per hospital, an average baseline
mortality rate of 38% and an intraclass correlation of
0.00408,18 a relative reduction in mortality by 8% due
to clinical PR could be detected with a power of 80%
using a t- test for unpaired samples.
Hospital and patient characteristics in the preinter-
vention period were analysed using descriptive statis-
tical techniques. Confirmatory analysis was based on
a difference- in- difference approach considering the
difference between intervention and control group
hospitals with respect to changes in the age- adjusted
and sex- adjusted standardised mortality ratio (SMR) in
the postintervention period compared with the prein-
tervention period. We applied weighted least squares
(WLS) regression with the change in the hospitals’
SMRs as a dependent variable and a dummy for inter-
vention group hospitals as an independent variable. A
t- test of the intervention group dummy was used to
assess the statistical significance of the treatment effect.
The number of cases ventilated for more than 24 hours
during the observation period at each hospital was used
as weight to account for different precisions of SMR
estimates. All observation arm hospitals in 2016 were
used as an external reference group to derive expected
mortality rates required for the calculation of SMRs.
In this regard, we verified that expected mortality
rates could be derived for all patient strata treated
in intervention and control group hospitals within
the study period. Subgroup analyses were conducted
for patients ventilated for more than 24 hours with
myocardial infarction, stroke, pneumonia, COPD and
colorectal resection, respectively. For these analyses,
we considered the point estimate of the coefficient of
the intervention group dummy and its 95% CI. The
confirmatory analyses reported in this paper were
complemented by comprehensive sensitivity analyses,
including adjustment for covariates, individual- level
regressions, time lags and time- varying effects of the
intervention (see online supplemental material). Statis-
tical analyses were conducted using Stata V.15.1.
RESULTS
Treatment allocation and hospitals included in final
analysis
Two hundred and thirty- seven hospitals agreed to
participate (figure 2). Fourteen did not treat patients
ventilated for more than 24 hours in 2016 and
therefore were not eligible. From the remaining 223
hospitals, the 60 hospitals with the highest mortality
rates in 2016 were randomised into intervention and
control groups with an allocation ratio of 1:1. While
all intervention group hospitals were included in
the analysis, one control group hospital was ‘lost to
follow- up’ due to a merger within the study period.
Accordingly, the analyses were based on data from
30 intervention and 29 control group hospitals with
12 085 and 13 016 cases of patients ventilated for
more than 24 hours during the pretreatment and post-
treatment periods, respectively.
Baseline characteristics of hospitals and patients
Block randomisation resulted in similar characteris-
tics in intervention and control group hospitals with
respect to number of beds and hospital ownership in
the preintervention period (table 1). The intervention
group hospitals were characterised by a higher median
number of ventilation cases than the control group
hospitals but showed a similar IQR. The baseline
mortality rates in ventilation patients were 40.6% and
41.9% in the intervention and control groups, respec-
tively. There were no relevant differences in terms of
age, sex and the shares of the considered subgroups
(myocardial infarction, stroke, pneumonia, COPD,
colorectal resection) in ventilation patients.
Main results
SMRs of the control group hospitals (SMR=1.28) and
the intervention group hospitals (SMR=1.23) were
similar in the preintervention period (figure 3). The
Figure 2 Flow chart showing allocation of hospitals to study groups and
inclusion in final analyses. IMPRESS, ‘Effectiveness of the IQM peer review
procedure to improve in- patient care—a pragmatic cluster randomized
controlled trial’.
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SMRs of both groups remained almost unchanged
in the postintervention period (control: SMR=1.29;
intervention: SMR=1.26).
These findings were also reflected in the results of
the difference- in- difference analysis. The WLS regres-
sion yielded a statistically insignificant point estimate
(estimate=0.04, 95% CI= −0.05 to 0.13, p=0.38) of
the intervention effect. Hence, there was no evidence
for a beneficial effect of clinical PR on mortality in
patients ventilated for more than 24 hours. All sensi-
tivity analyses were in line with this result as they did
not provide evidence for a treatment effect (see online
supplemental material).
Subgroup analyses
We also estimated the potential effects of the clinical
PR on mortality in patients ventilated for more than 24
hours with myocardial infarction, stroke, pneumonia,
COPD and colorectal resection, respectively. In line
with the main results outlined above, the point esti-
mates and 95% CIs did not indicate a treatment effect
in these subgroups (figure 4). More detailed informa-
tion is provided in online supplemental table S2.
Survey findings
We conducted the impact and process improvement
survey from 7 January 2019 to 30 April 2019 and sent
a reminder on 18 March 2019. The final response rate
was slightly higher in the intervention group (26/30;
80%) compared to the control group (20/29; 69%).
A minority of intervention hospitals (5/26) and
control hospitals (7/20) indicated that they had
received a clinical PR on ventilation prior to partic-
ipating in the current cluster randomized controlled
Table 1 Baseline (preintervention period) characteristics of hospitals and patients ventilated for more than 24 hours
Study group Intervention group Control group
Variable n/Median %/Q1; Q3 n/Median %/Q1; Q3
Hospital characteristics n=30 hospitals n=29 hospitals
Number of beds, n (%)
1–149 3 10.0 3 10.3
150–299 10 33.3 9 31.0
300–599 12 40.0 10 34.5
600+ 5 16.7 7 24.1
Hospital ownership, n (%)
Non- profit 8 26.7 8 27.6
Private 7 23.3 5 17.2
Public 15 50.0 16 55.2
Ventilation cases per hospital, median (Q1; Q3) 161 82; 267 129 78; 255
Patient characteristics n=6038 cases n=6586 cases
Age, median (Q1; Q3) 71 60; 79 70 58; 78
Sex, n (%)
Female 2368 39.2 2603 39.5
Male 3670 60.8 3983 60.5
In- hospital death, n (%)
No 3584 59.4 3827 58.1
Yes 2454 40.6 2759 41.9
Myocardial infarction, n (%)
No 5708 94.5 6295 95.6
Yes 330 5.5 291 4.4
Stroke, n (%)
No 5625 93.2 6015 91.3
Yes 413 6.8 571 8.7
Pneumonia, n (%)
No 5597 92.7 6087 92.4
Yes 441 7.3 499 7.6
Chronic obstructive pulmonary disease (COPD), n (%)
No 5572 92.3 6186 93.9
Yes 466 7.7 400 6.1
Colorectal resection, n (%)
No 5957 98.7 6523 99.0
Yes 81 1.3 63 1.0
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trial. We extracted 132 recommendations for quality
improvement from the intervention group hospi-
tals’ lists of recommendations for improvement. The
majority (116/132, 88%) of these recommendations
were transferred unchanged (n=82) or modified
(n=34) into an action plan.
Overall, 81 recommendations for quality improve-
ment measures were already implemented or about to
Figure 3 Evolution of standardised mortality ratios (SMRs) in intervention and control group hospitals with 95% CIs.
Figure 4 Results of weighted least squares (WLS) regressions for subgroups of patients ventilated for more than 24 hours with 95% CIs. COPD=chronic
obstructive pulmonary disease.
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be implemented in the intervention group hospitals
at the time of the survey. Most of the implemented
recommendations aimed at improving procedures and
structures of care including documentation (26/81),
care strategies (16/81) and updated/additional stan-
dard operating procedures (11/81). Two- thirds of
these implemented recommendations were rated by
experts as ‘likely irrelevant’ (median rating=3–3.5:
21/81; 26%) or ‘almost surely irrelevant’ (median=4:
32/81; 40%) for in- hospital mortality in patients
ventilated for more than 24 hours. Recommenda-
tions targeting improvements in documentation were
rated as ‘likely irrelevant’ or ‘almost surely irrelevant’.
Implemented recommendations targeting treatment
protocols of ventilation or reanimation were rated as
‘likely relevant’.
The quantitative evaluation of implemented
measures by participating intervention hospitals indi-
cated a fairly high level of perceived structural and
procedural (19/26; 73%) improvements. The qual-
itative evaluation described improvements due to
structural recommendations, particularly in the form
of new standards and infrastructures (11 quotes).
Procedural recommendations leading to improvement
were noted in 31 quotes addressing care processes or
documentation. In line with the results of the main
outcome analysis, perceived reductions in mortality
of ventilated patients were rarely reported (three
quotes).
DISCUSSION
This study improves upon previous observational
research10–12 on the effects of clinical PR as a measure
to improve the quality of care in intensive care medi-
cine. Neither the main results nor the subgroup and
sensitivity analyses provided evidence for a beneficial
effect of clinical PR regarding ventilation on mortality
in patients ventilated for more than 24 hours. In line
with these results, the hospital survey indicated that
many of the recommendations made to improve the
quality of care had been implemented, but that these
measures were not considered to have a direct impact
on the mortality rates in patients ventilated for more
than 24 hours.
The survey results showed that clinical PR was
perceived positively by the participating hospitals and
many measures recommended during clinical PR were
implemented in intervention group hospitals. The
expert rating indicated that most of these measures
were not seen as directly related to mortality in venti-
lated patients. This reflects that many potentials for
improvement were identified which did not directly
affect mortality but may have had other beneficial
effects. If the above- average baseline mortality in the
participating hospitals was driven by deficits in quality
of care, clinical PR may not, therefore, have adequately
identified these deficits.
Strengths and limitations
This study used a randomised design to prevent
regression to the mean, unmeasured confounding
and selection biases, and to ensure a high degree of
generalisability. A limitation of the study is that, due
to the study design, the effectiveness of clinical PR
as a complex intervention could only be assessed
as a whole and its impacts on outcomes other than
mortality were not captured. The high number of
measures recommended during clinical PR may
primarily affect process quality, which was not consid-
ered as an outcome. However, in line with the value-
based healthcare framework,19 patients are mainly
interested in health outcomes rather than the struc-
tural or procedural quality of care.
The reliability of judgements by reviewers and the
adequacy of recommended measures for improve-
ment of inpatient care are crucial if clinical PR is
to be effective. The IQM clinical PR is strictly stan-
dardised regarding both training and implementa-
tion. The IQM clinical PR report addresses specific
topics related to the quality of care, including struc-
tures and especially processes. The clinical PR team
represents different professions (physicians, nurses),
specialties (eg, anaesthesiology, pulmonology) and
hierarchical positions (eg, senior physicians, resident
physicians). We believe that the high degree of stan-
dardisation and the interdisciplinary and interpro-
fessional nature of the IQM clinical PR are likely to
facilitate adequate judgements of potentials and flaws
and facilitate the derivation of suitable measures
for improvement. However, all these advantages
did not translate into mortality benefit for patients.
Due to its focus on clinical structures and processes,
the IQM clinical PR does not consider external drivers
of poor quality and patient outcomes, including char-
acteristics of the healthcare system. Therefore, iden-
tifying those external potentials for improvement
requires different complementary approaches.
Another limitation of our study is the possibility
that intervention effects may have evolved over time
and that longer follow- up may have been valuable.
However, sensitivity analyses did not provide support
for time- varying intervention effects (see online
supplemental material).
Despite the robustness of our findings against
adjustment for multiple patient characteristics in sensi-
tivity analyses (see online supplemental material), the
persistence of above- average mortality in both inter-
vention and control hospitals may be due to patient-
associated risk not captured by our data. While our data
provide information on patient- specific risk factors for
mortality, for example, in terms of Elixhauser comor-
bidities, some clinical indicators of disease severity
(eg, laboratory and imaging findings) could not be
operationalised. However, since our study relies on
a randomised design, we do not expect systematic
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differences between intervention and control groups
regarding those characteristics.
In line with IQM methodology, the selection of
intervention and control hospitals was based on the
assumption that hospitals with the highest mortality
rates in specific patient groups have the largest poten-
tial for improvement in terms of quality of care.
Although previous observational studies on IQM clin-
ical PR seemed to support this assumption, we cannot
exclude that modifiable mortality in the participating
hospitals was actually too low to induce a significant
intervention effect.
This study did not investigate differences between
hospitals with low and high mortality rates in patients
ventilated for more than 24 hours in terms of care
characteristics (eg, use of lung- protective ventilation
or measures aimed at preventing ventilator- associated
pneumonia). Investigating such differences could
shed more light on mortality- relevant potentials for
improvement and could be used to derive suitable
quality standards for future clinical PRs.
Finally, this study examined the effectiveness of IQM
clinical PR. The extent to which our results are gener-
alisable to other variants of clinical PR may depend on
specific methodological aspects, including the degree
to which the considered clinical PR procedure focuses
on measures related to mortality.
Implications
The COVID- 19 pandemic has highlighted the role
of long- term ventilation as a key element in the care
of critically ill patients.1 Ensuring and improving
the quality of care of ventilation patients is the main
objective of this study. The lack of outcome improve-
ments indicated by our analysis has major implica-
tions for the conceptualisation of clinical PR. Potential
modifications of the clinical PR procedure include a
more specific focus on outcome quality and stricter
monitoring of changes in structures and procedures
after clinical PR. Those modifications would require
enhanced identification of mortality- relevant care
processes and targeted measurement of mortality
related to these processes.
Alternatively, the focus of future clinical PR may be
shifted from outcome quality towards process quality.
The latter would require measurement of process-
related outcomes to assess effectiveness and different
triggers for clinical PR. Modification of clinical PR
may also require improved training of clinical PR
teams, better documentation in lists of recommenda-
tions for improvement and more emphasis on imple-
mentation of sustainable measures. These issues have
been recognised by the IQM steering group, which
defined an action plan regarding the IQM clinical PR
method. IQM clinical PR reports and trainings have
been restructured with stronger focus on potentials to
reduce mortality.
A general implication of this study is that the effec-
tiveness of the clinical PR is under scrutiny. As with all
complex interventions, reliable evidence on the effec-
tive components of clinical PR is required to improve
the method and justify its continued use.
Author affiliations
1Zentrum für Evidenzbasierte Gesundheitsversorgung, Universitätsklinikum Carl
Gustav Carus, Dresden, Germany
2Initiative Qualitätsmedizin (IQM), Berlin, Germany
3Quality and Medical Risk Management, University Hospital Carl Gustav Carus
Dresden, Dresden, Germany
4Koordinierungszentrum für Klinische Studien, Medizinische Fakultät Carl
Gustav Carus der Technischen Universität Dresden, Dresden, Germany
Acknowledgements The authors thank Jochen Strauß, Claudia
Winklmair, the IQM executive board and all participating
hospitals.
Contributors JS and OS designed the study. MR and XG
prepared the RCT data. MR analysed the RCT data. JS, FW
and OS validated the analyses. FW and OS designed the
hospital survey. FW analysed the survey data. PS, ME- G and
RK provided clinical and methodological expertise regarding
IQM peer review. All authors discussed and interpreted the
empirical findings. MR drafted the manuscript and all the
remaining authors critically revised the manuscript. JS is
responsible for the overall content as guarantor.
Funding This study was funded by the Joint Federal Committee
(Gemeinsamer Bundesausschuss, G- BA), Germany (grant
number: 01VSF16013).
Competing interests All authors report grant from
Innovationsfonds des GBA for the conduct of the study. JS
reports grants from ALK, Novartis, Pfizer, Sanofi; personal
fees from ALK, Novartis, Lilly, Sanofi outside the submitted
work. OS reports personal fees from Novartis outside the
submitted work. RK reports that as an employee of Helios, a
subsidiary of Fresenius, he is working for a healthcare company
and is holding Fresenius stocks and stock options. XG reports
grants from the German Federal Ministry of Health during the
conduct of the study. XG further reports grants from Dräger
AG & Co KGaA, Aesculap, Gesundheitsforen Leipzig, Novartis
Pharma, University of Rostock and medichema outside the
submitted work.
Patient consent for publication Not required.
Ethics approval Institutional Review Board (IRB) TU Dresden:
Office for Human Research Protections (OHRP); identification
numbers: IRB00001473 and IORG0001076.
Provenance and peer review Not commissioned; externally
peer reviewed.
Data availability statement No data are available. Data are not
publicly available due to confidentiality restrictions.
Supplemental material This content has been supplied by the
author(s). It has not been vetted by BMJ Publishing Group
Limited (BMJ) and may not have been peer- reviewed. Any
opinions or recommendations discussed are solely those of
the author(s) and are not endorsed by BMJ. BMJ disclaims
all liability and responsibility arising from any reliance placed
on the content. Where the content includes any translated
material, BMJ does not warrant the accuracy and reliability of
the translations (including but not limited to local regulations,
clinical guidelines, terminology, drug names and drug dosages),
and is not responsible for any error and/or omissions arising
from translation and adaptation or otherwise.
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, appropriate
credit is given, any changes made indicated, and the use is non-
on November 10, 2022 by guest. Protected by copyright.http://qualitysafety.bmj.com/BMJ Qual Saf: first published as 10.1136/bmjqs-2021-013864 on 5 April 2022. Downloaded from
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Original research
commercial. See: http://creativecommons.org/licenses/by-nc/4.
0/.
ORCID iDs
Martin Roessler http://orcid.org/0000-0002-4662-4156
Olaf Schoffer http://orcid.org/0000-0001-6922-7148
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