Critical Analysis of Research Methodologies: DAPT and CABG

This report provides a critical review of the research methodologies employed in the article "Dual Antiplatelet Therapy before Coronary Artery Bypass Grafting; a Systematic Review and Meta-Analysis." The report begins with an introduction to research methodology, emphasizing the importance of understanding the methods used in a study to assess its strengths and weaknesses. The main body of the report focuses on the specific methodologies used in the article, including the PICO framework for developing the research question, the use of systematic review and meta-analysis, and the search strategies used to identify relevant studies. The report also discusses the advantages and limitations of systematic reviews and meta-analyses. The study design, inclusion and exclusion criteria, data extraction, and risk of bias assessment are also discussed. The report concludes by summarizing the findings and limitations of the original article, highlighting that dual antiplatelet therapy before CABG does not maximize the rate of mortality, renal failure, and other cardiac events, but it does maximize the length of ICU stay, re-exploration, and hospital stay. The report notes the moderate level of evidence and the need for further clinical trials to reach definitive conclusions.

Analyse and critically review one of the
below topics use in the appropriate
critical appraisals skills program tools
1

CONTENTS
TITLE – “Dual Antiplatelet Therapy before Coronary Artery Bypass Grafting; a Systematic
Review and Meta-Analysis”............................................................................................................3
INTRODUCTION...........................................................................................................................3
MAIN BODY..................................................................................................................................3
Critical review of the research methodologies uses in article “Dual Antiplatelet Therapy before
Coronary Artery Bypass Grafting; a Systematic Review and Meta-Analysis”...........................3
CONCLUSION................................................................................................................................6
REFERENCES................................................................................................................................7
2

TITLE – “Dual Antiplatelet Therapy before Coronary Artery Bypass Grafting; a
Systematic Review and Meta-Analysis”
INTRODUCTION
Research methodology can be stated as a path by which the researchers required to perform
the research. It depicts the path by which problem and objective is formulated and findings from
the data are presented. Research methodology demonstrates the way research outcome will be
acquired in line with mitigating the objectives of the study. Research methodology outlines
research approach, research philosophy, research design, research strategy, data collection
methods, sampling etc. Critical review of research methodology includes demonstrating a proper
understanding about the methods utilise in the research. It assists in determining the strengths
and weaknesses of research methods utilized in the study. This study is based on the critical
review and analysis of the research methodologies included in the article named as “Dual
Antiplatelet Therapy before Coronary Artery Bypass Grafting; a Systematic Review and Meta-
Analysis.” This report covers in-depth analysis, discussion and justification of methodologies
utilised in the article. Apart from this, a summary of the overall review is providing at the end in
order to demonstrate an understanding of reliability and validity of research study.
MAIN BODY
Critical review of the research methodologies uses in article “Dual Antiplatelet Therapy before
Coronary Artery Bypass Grafting; a Systematic Review and Meta-Analysis”
The article “Dual Antiplatelet Therapy before Coronary Artery Bypass Grafting; a
Systematic Review and Meta-Analysis” aims to answer that should Dual Antiplatelet Therapy
(DAPT) with clopidogrel and Aspirin be continued up until coronary artery bypass grafting
(CABG) in patients with acute coronary syndrome (ACS)? It was a systematic review and the
author of the article are Roxana Sadeghi, Arash Sarveazad, Asrin Babahajian, Naser Kachoueian,
and Mansour Bahardoust. The article was published in year 2020 and the search of relevant
studies is based on three approaches in this meta-analysis. These three approaches include
manual searches in Google scholar in Google, systematic searches in electronic database and
screening of bibliography of associated review and original articles.
For developing the research question in this study, researchers were used PICO framework
which is used in evidence based practice in order to develop and answer health or clinical care
3

related question. As the study is based on dual antiplatelet therapy (DAPT) before coronary
artery bypass grafting, PICO framework is an appropriate process to develop research question.
In this particular study, it is also utilized to formulate literature search strategies, for example -
systematic reviews. A systematic review can be referred as a review of evidence on clearly
developed question that utilizes explicit and systematic methods in order to determine, choose
and critically appraise relevant primary investigation as well as to extract and assess data from
the studies which are involved in the review. The detailing of an engaged clinical inquiry
containing all around expressed PICO components is generally accepted to be the way to
productively discovering excellent proof and furthermore the way to prove based decisions.
PICO outlines initially created for treatment questions were later reached out to a wide range of
clinical inquiries. Empirical examinations have indicated that the utilization of PICO outlines
improves the explicitness and calculated clearness of clinical problems, inspires more data
during pre-search reference interviews, prompts more perplexing pursuit systems, and yields
more exact list items
The selected paper is a systematic review study in which the scope of review is determined
in advance and comprehensive search was done to find out relevant studies. In order to critically
appraise the study quality, execution of established standards was done by the researches and the
study includes meta-analysis. According to the analysis it has been evaluated that systematic
review offer various advantages. First of all, they convey an unmistakable and extensive diagram
of accessible proof on a given theme. In addition to this, it has been evaluated that, systematic
review additionally helps distinguish research holes in our flow comprehension of a field. They
can feature methodological worries in examination considers that can be utilized to improve
future work in the subject area. In conclusion, they can be utilized to recognize inquiries for
which the accessible proof gives clear answers. The main purpose of using systematic review in
the study was to determine, evaluate as well as summarize the outcomes of all the relevant
studies over the issue associated with health, thereby making available evidence accessible to
decision makers. However, there are some limitations of using systematic review in the study.
The alternative questions which have not been answered, usually require to be reconstructed
through the reader. Apart from this, systematic review with the narrowly defined review question
administers specific answers to particular question. This PICO question in relation to this
particular study is provided below:
4

Population (P) Coronary Artery Bypass Grafting (CABG) candidates
Intervention (I) Dual Antiplatelet Therapy (DAPT) with clopidogrel and aspirin
Comparison (C) Comparison with the control group (non-antiplatelet therapy or aspirin
alone)
Outcomes (O) Mortality rate, reoperation, myocardial infarction (MI), renal failure,
cerebrovascular accident (CVA), other cardiac events, re-exploration,
length of hospital stay and ICU, chest tube drainage, and requirement
for blood product transfusion after Coronary Artery Bypass Grafting
(CABG)
In this particular study, the study design was based on PICO process in which is a tool
utilized by researchers to determine constituents of medical evidence for systematic reviews in
the medicine, which is evidence based and is endorsed through the Cochrane Collaboration. The
PICO parameters in this study were clearly defined and these are the central to this evidence
based study.
The systematic review strategy utilised in this study gathers all possible studies associated
with the research topic as well as the design, and review and assess the outcomes. During the
process of systematic review, the authors evaluate the quality of study and a statistical meta-
analysis of study outcomes is performed on the basis of quality. On the other hand, meta-analysis
is a scientific, objective and valid method analysing as well as combining distinct outcomes. The
meta-analysis and systematic review presents outcomes through combining and assessing data or
information from distinct studies performed on similar topics of research. These methods of
research are powerful tools which can overcome difficulties in conducting large scale
randomised control trials.
However, different guidelines have been provided for performing meta-analysis and
systematic reviews to assist standardized them as well as enhance their quality. For securing
proper basis of evidence based study, the researches performed broad search which involves
various studies to mitigate the exclusion and inclusion criteria. In this particular study, the
researchers were studied 41 articles in detail and in this meta-analysis, the data from 15 studies
were finally included (Sadeghi, Babahajian, Sarveazad, Kachoueian, and Bahardoust, 2020). The
main aim of utilising meta-analysis and systematic literature review is to assist extract good
5

quality and accurate data from ample of data being produced in better manner. However, if the
evidence quality in study is low, then the quality of meta-analysis is decline and inaccurate
outcomes can be acquired.
The search strategy utilised in this study include some keywords which were selected
through consulting with an expert, utilising Emtree and MeSH and screening of associated
journals and articles. Then, searches were conducted in Scopus, Embase, Web of Science and
Medline databases separately. The keywords used for searching the data includes reoperation,
mortality rate, cerebrovascular accident, renal failure, myocardial infection, chest tube drainage
etc. This strategy assisted researches in searching ample amount of information on the topic in an
appropriate way. In this present meta-analysis study, quasi experimental, controlled and clinical
trials studies which evaluated dual antiplatelet therapy with clopidogrel and aspirin before
coronary artery bypass grafting surgery without applying any limitations regarding age,
ethnicity, language, sex, time were involved. The exclusion criteria for the study was that this
study did not include the studies which utilised clopidogrel or aspirin alone as treatment group,
retracted articles and studies without control group.
For the extraction of data in this study, the search records were imported by the authors into
EndNote software as well as the duplicated studies were eliminated. The abstract and title of
search results were screened by two independent reviewers and after careful analysis of studies,
information or data were extracted as well as summarised in data extraction form. If there was
disagreement between the two reviewers, third reviewer determined outcomes of discussions
with two other reviewers as well as the relevant data was imported. The data extracted in the
study involved name of the first author, study type, sample size, publication year, interval
between discontinuation and surgery, country, age and outcomes. In case the data or information
could not be extracted, the investigator asked corresponding author to administer data. With the
guidelines proposed by Cochrane, the risk of bias analysis of cohort studies was analysed in this
study. By utilising National Institute of Health quality assessment tool for cross sectional and
observational cohort studies, the risk of bias assessment was performed.
Aside from this, all the significant and significant investigations were remembered for this
paper which guarantees more dependable after-effects of the examination. In this specific
investigation performed by the creators, the quality control of studies portrayed that blinding had
not been executed. To survey the nature of included examinations, three methodologies were
6

used by the writer which includes deliberate quests in electronic information bases, screening of
reference index of related audit articles and manual pursuit in Google researcher, Google and
more. The utilization of website pages and google researcher helped with social event sufficient
measure of data on the point that contributed the creators in drawing fitting results of study. This
helped creators in guaranteeing that the information gathered for the investigation is of high
caliber and solid which guarantees legitimate results of study. The results of the survey have
been consolidated successfully in this specific examination and the outcomes were unmistakably
shown in the paper in even structure. Furthermore, the general results of the audit were
introduced fittingly in the investigation nonetheless, because of absence of blinding in a large
portion of the examinations, it portraying the presence of likely eyewitness inclination in the
examination. Aside from this, the vast majority of the include the investigations were
imminent/review companions and to reach to authoritative resolution, further clinical
preliminaries are required.
In relation to this specific study, all the crucial outcomes that were considered include the
findings of the study along with the limitations provided in the paper as this assist the authors in
performing the further study in more effective way on the topic and the limitations can be
eliminated. Apart from this, is the level of evidence shown in cohort studies is low in comparison
to clinical trials, the evidence level presented in this particular study was moderate. In addition to
this, major bleeding had been reported in two studies only, therefore it was not possible for the
authors to present outcomes in this regard.
By reviewing the overall study, it has been found that the review addresses the really
focused question. 41 studies were studied descriptively in the initial screening and 15 were
selected from those studies. It has been found from the study that dual antiplatelet therapy before
coronary artery bypass grafting in patients with acute coronary syndrome does not maximize the
rate of mortality, renal failure, myocardial interaction, cerebrovascular accident and other cardiac
events but, maximize the length of Intensive Care unit, re-exploration, re-operation and hospital
stay. Blood product transfusion rate and chest tube drainage in dual antiplatelet therapy
compared to control group increased significantly. This increment in blood product transfusion
rate and chest tube drainage depicts rise in bleeding, thus, increase in re-exploration and re-
operation in order to control bleeding and subsequently maximize in hospital stay and length of
Intensive Care unit stay is expected.
7

The authors in the study look for the right type of papers for reviewing in the study and an
appropriate study design was selected for evaluating the papers. Apart from this, all the relevant
and important studies were included in this paper which ensures more reliable results of the
study. In this particular study performed by the authors, the quality control of studies depicted
that blinding had not been executed. In order to assess the quality of involved studies, three
approaches were utilised by the authors which involves systematic searches in electronic data
bases, screening of bibliography of associated review articles and manual search in Google
scholar, web pages and Google. The use of web pages and google scholar assisted in gathering
ample amount of information on the topic that contributed the authors in drawing appropriate
outcomes of study. This assisted authors in ensuring that the data collected for the study is of
high quality and reliable which ensures valid outcomes of study. The outcomes of the review
have been combined effectively in this particular study and the results were clearly displayed in
the paper in tabular form. In addition to this, the overall outcomes of the review were presented
appropriately in the study however, due to lack of blinding in most of the studies, it depicting the
existence of probable observer bias in the study. Apart from this, most of the involve the studies
were prospective/ retrospective cohorts and in order to reach to definitive conclusion, further
clinical trials are required.
CONCLUSION
As per the above mentioned report, it has been concluded that research philosophy is the
way through which investigator need to lead their examination. It shows the way through which
these analysts plan their objectives and problem and significantly present their outcome from the
information acquired during the examination time frame. With the help of different types of
methodology present research has been accomplished in a well defined and effective manner. It
has been evaluated that research methodology play significant role that allows investigator to
fulfil research aim and objectives in a well define and effective manner. This significantly
enhances effectiveness of research.
8

REFERENCES
Books and Journals
Sadeghi, R., Babahajian, A., Sarveazad, A., Kachoueian, N. and Bahardoust, M., 2020. Dual
Antiplatelet Therapy before Coronary Artery Bypass Grafting; a Systematic Review and
Meta-Analysis. Archives of Academic Emergency Medicine, 8(1).
Tomšič, A., Schotborgh, M.A., Manshanden, J.S., Li, W.W. and de Mol, B.A., 2016. Coronary
artery bypass grafting-related bleeding complications in patients treated with dual
antiplatelet treatment. European Journal of Cardio-Thoracic Surgery, 50(5), pp.849-856.
Vuilliomenet, T., Gebhard, C., Bizzozero, C., Glauser, S., Blum, S., Buser, A., Bolliger, D.,
Grapow, M.T. and Siegemund, M., 2019. Discontinuation of dual antiplatelet therapy and
bleeding in intensive care in patients undergoing urgent coronary artery bypass grafting: a
retrospective analysis. Interactive cardiovascular and thoracic surgery, 28(5), pp.665-
673.
Mahla, E., Prueller, F., Farzi, S., Pregartner, G., Raggam, R.B., Beran, E., Toller, W., Berghold,
A., Tantry, U.S. and Gurbel, P.A., 2016. Does platelet reactivity predict bleeding in
patients needing urgent coronary artery bypass grafting during dual antiplatelet
therapy?. The Annals of thoracic surgery, 102(6), pp.2010-2017.
Valgimigli, M., Bueno, H., Byrne, R.A., Collet, J.P., Costa, F., Jeppsson, A., Jüni, P., Kastrati,
A., Kolh, P., Mauri, L. and Montalescot, G., 2018. 2017 ESC focused update on dual
antiplatelet therapy in coronary artery disease developed in collaboration with
EACTS. European journal of cardio-thoracic surgery, 53(1), pp.34-78.
Holm, M., Biancari, F., Khodabandeh, S., Gherli, R., Airaksinen, J., Mariscalco, G., Gatti, G.,
Reichart, D., Onorati, F., De Feo, M. and Santarpino, G., 2019. Bleeding in patients
treated with ticagrelor or clopidogrel before coronary artery bypass grafting. The Annals
of thoracic surgery, 107(6), pp.1690-1698.
Ebrahimi, R., Bakaeen, F.G., Uberoi, A., Ardehali, A., Baltz, J.H., Hattler, B., Almassi, G.H.,
Wagner, T.H., Collins, J.F., Grover, F.L. and Shroyer, A.L., 2014. Effect of clopidogrel
use post coronary artery bypass surgery on graft patency. The Annals of Thoracic
Surgery, 97(1), pp.15-21.
Hansson, E.C., Jidéus, L., Åberg, B., Bjursten, H., Dreifaldt, M., Holmgren, A., Ivert, T.,
Nozohoor, S., Barbu, M., Svedjeholm, R. and Jeppsson, A., 2016. Coronary artery bypass
grafting-related bleeding complications in patients treated with ticagrelor or clopidogrel:
a nationwide study. European heart journal, 37(2), pp.189-197.
Alfredsson, J., Neely, B., Neely, M.L., Bhatt, D.L., Goodman, S.G., Tricoci, P., Mahaffey, K.W.,
Cornel, J.H., White, H.D., Fox, K.A. and Prabhakaran, D., 2017. Predicting the risk of
bleeding during dual antiplatelet therapy after acute coronary syndromes. Heart, 103(15),
pp.1168-1176.
Rafiq, S., Johansson, P.I., Kofoed, K.F., Lund, J.T., Olsen, P.S., Bentsen, S. and Steinbrüchel,
D.A., 2017. Thrombelastographic hypercoagulability and antiplatelet therapy after
coronary artery bypass surgery (TEG-CABG trial): a randomized controlled
trial. Platelets, 28(8), pp.786-793.
9