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Copyright © 2021 pubrica. All rights reserved 1
How to structure your Table for Systematic
Review and Meta-analysis
Dr. Nancy Agnes, Head, Technical Operations, Pubrica sales@pubrica.com
Keywords:
systematic review, meta-analysis, writing a
systematic review, meta-analysis writing, Data
extraction, effect sizes for meta-analysis, systematic
review process, write up the systematic study.
In Brief
According to the, a systematic review is "a scholarly
method in which all empirical evidence that meets
pre-specified eligibility requirements is gathered to
address a particular research question." It entails
systematically identifying, selecting, synthesising,
and evaluating primary research studies to produce
a high-quality summary of a subject while
addressing a pre-specified research question. A
meta-analysis is a step forward from a systematic
review in that it employs mathematical and
statistical methods to summarise the results of
studies included in the systematic review(1)
.
I. INTRODUCTION
In some aspects, systematic reviews vary from
conventional narrative reviews. Narrative reviews are
mostly descriptive, do not require a systematic search
of the literature, and concentrate on a subset of
studies in a field selected based on availability or
author preference. As a result, although narrative
reviews are informative, they often include an
element of selection bias. As the name implies,
systematic reviews usually include a thorough and
comprehensive plan and search strategy derived a
priori to minimise bias by finding, evaluating, and
synthesising all related studies on a given subject. A
meta-analysis aspect is often used in systematic
reviews, which entails using statistical techniques to
synthesise data from several studies into a single
quantitative estimation or summary effect size. It is a
well-known and well-respected multinational non-
profit organisation that promotes, funds, and
disseminates systematic reviews and meta-analyses
on the effectiveness of healthcare interventions (2)
.
II. NEED OF SYSTEMIC REVIEW AND META-
ANALYSIS
There are several reasons for performing a systematic
review and meta-analysis:
 It may assist in resolving discrepancies in results
published by individual studies that may include
bias or errors.
 It may help identify areas in a field where there
is a lack of evidence and areas where further
research should be conducted.
 It allows the combination of findings from
different studies, highlighting new findings
relevant to practice or policy.
 It may be able to reduce the need for additional
trials.
 Writing a systematic review and meta-analysis
will help identify a researcher's field of interest
since they are published in high-impact journals
and receive many citations many citations (3)
.
III. PHASES TO PLANNING A SYSTEMATIC
REVIEW AND META-ANALYSIS
The succeeding components to a successful
systematic review and meta-analysis writing are:
 Formulate the Review Question
The first stage involves describing the review topic,
formulating hypotheses, and developing a title for the
review. It's usually best to keep titles as short and
descriptive as possible by following this formula:
Intervention for those with a disease (e.g., Dialectical
behaviour therapy for adolescent females with a
borderline personality disorder). Since reviews
published in other outlets do not need to be listed as
such, they should state in the title that they are a
systematic review and meta-analysis.
 Define inclusion and exclusion criteria
The PICO (or PICOC) acronym stands for
population, intervention, comparison, outcomes (and
context). It can help ensure that all main components
are decided upon before beginning the study. Authors
must, for example, choose their population age range,
circumstances, results, and type(s) of interventions
and control groups a priori. It's also crucial to
determine what types of experiments to include and
exclude (e.g., RCTs only, RCTs and quasi-
experimental designs, qualitative research), the
minimum number of participants in each group,
published and unpublished studies, and language
restrictions.
Copyright © 2021 pubrica. All rights reserved 2
 Develop a search strategy and locate studies
This is where a reference librarian can be
particularly beneficial in assisting with the
creation and execution of electronic searches. To
recognise all applicable trials in a given region, it
is essential to create a detailed list of key terms
(i.e., "MeSH" terms) related to each component
of PICOC. The secret to creating an effective
search strategy is to strike a balance between
sensitivity and precision.
 Selection of studies
After retrieving and reviewing a detailed list of
abstracts, any studies that tend to satisfy inclusion
requirements will be collected and thoroughly
reviewed. To ensure inter-raterreliability, this
procedure is usually carried out by at least two
reviewers. It is suggested that authors maintain a list
of all checked research, including reasons for
inclusion or exclusion. It might be possible to hire
study authors to collect missing data for data pooling
(e.g., means, standard deviations). It's also possible
that translations will be needed.
 Extract data
To organise the information extracted from each
reviewed study (e.g., authors, publication year,
number of participants, age range, study design,
results, included/excluded), building and using a
basic data extraction type or chart can be beneficial.
Data extraction by at least two reviewers is necessary
to ensure inter-rater reliability and prevent data entry
errors
Table: 1 outline for systemic review and meta-analysis
Background
Objectives
Review questions Types of patients, interventions, outcomes and studies
Search strategy Databases, study period, grey literature
Review Methods
Databases and article sources
Screening
Data extraction
Assessment of data quality
Data analysis
References
Copyright © 2021 pubrica. All rights reserved 3
 Assess study quality
In recent years, there has been a push to improve the
consistency of each RCT included in systematic
reviews. Double-blinding, which is acceptable for
clinical trials but not for psychological or non-
pharmacological treatments, significantly impacts this
metric. Other more detailed guidelines and criteria,
such as the Consolidated Standards of Reporting
Trials (CONSORT), as well as articles with
recommendations for improving quality in RCTs and
meta-analyses for psychological intervention, are
available(4)
.
 Analyse and Interpret results
The Review Manager (RevMan) software, endorsed
by the Cochrane Collaboration, is one example of a
statistical programme that can measure effect sizes
for meta-analysis. The effect sizes are given, along
with a 95 percent confidence interval (CI) range, and
are presented in both quantitative and graphical form
(e.g., forest plots). Each trial is visually represented
as a horizontal diamond shape in forest plots. The
middle represents the effect size (e.g., SMD) and the
endpoints representing both ends of the CI.
 Disseminate findings
Since the Cochrane Collaboration's reviews are
published in the online Cochrane Database of
Systematic Reviews, they are often lengthy and
comprehensive. As a result, it is possible and
encouraged to publish abbreviated versions of the
review in other applicable scholarly journals; indeed,
engaging in a review update or joining a well-
established review team may be a beneficial way to
get involved in the systematic review process.
IV. FUTURE SCOPE
The systematic review's findings should be discussed
in terms of the strength of evidence and shortcomings
of the initial research used for the review. It's also
necessary to discuss the review's weaknesses, the
results' applicability (generalizability), and the
findings' implications for patient care, public health,
and future clinical research (5)
.
V. CONCLUSION
The steps of a systematic review/meta-analysis
include developing a research question and validating
it, forming criteria, searching databases, importing all
results to a library and exporting to an excel sheet,
protocol writing and registration, title and abstract
screening, full-text screening, manual searching,
extracting data and assessing its quality, data
checking, and conducting statistics. The PRISMA or
Meta-analysis must be used to write up the systematic
study and meta-analysis. This is a reporting checklist
for systematic literature reviews and meta-analyses
that specifies what information should be included in
each portion of a high-quality systematic review (6)
.
REFERENCES
1. Alonso Debreczeni, Felicia, and Phoebe E.
Bailey. "A systematic review and meta-analysis
of subjective age and the association with
cognition, subjective well-being, and
depression." The Journals of Gerontology: Series
B 76.3 (2021): 471-482.
2. Vasconcellos, Diego, et al. "Self-determination
theory applied to physical education: A
systematic review and meta-analysis." Journal of
Educational Psychology 112.7 (2020): 1444.
3. Geary, William L., et al. "Predator responses to
fire: A global systematic review and meta‐
analysis." Journal of Animal Ecology 89.4
(2020): 955-971.
4. Donald, James N., et al. "Mindfulness and its
association with varied types of motivation: A
systematic review and meta-analysis using self-
determination theory." Personality and Social
Psychology Bulletin 46.7 (2020): 1121-1138.
5. Madigan, Sheri, et al. "Associations between
screen use and child language skills: A
systematic review and meta-analysis." JAMA
paediatrics 174.7 (2020): 665-675.
6. McArthur, Genevieve M., et al. "Self-concept in
poor readers: a systematic review and meta-
analysis." PeerJ 8 (2020): e8772.

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How to structure your table for systematic review and meta analysis – Pubrica

  • 1. Copyright © 2021 pubrica. All rights reserved 1 How to structure your Table for Systematic Review and Meta-analysis Dr. Nancy Agnes, Head, Technical Operations, Pubrica sales@pubrica.com Keywords: systematic review, meta-analysis, writing a systematic review, meta-analysis writing, Data extraction, effect sizes for meta-analysis, systematic review process, write up the systematic study. In Brief According to the, a systematic review is "a scholarly method in which all empirical evidence that meets pre-specified eligibility requirements is gathered to address a particular research question." It entails systematically identifying, selecting, synthesising, and evaluating primary research studies to produce a high-quality summary of a subject while addressing a pre-specified research question. A meta-analysis is a step forward from a systematic review in that it employs mathematical and statistical methods to summarise the results of studies included in the systematic review(1) . I. INTRODUCTION In some aspects, systematic reviews vary from conventional narrative reviews. Narrative reviews are mostly descriptive, do not require a systematic search of the literature, and concentrate on a subset of studies in a field selected based on availability or author preference. As a result, although narrative reviews are informative, they often include an element of selection bias. As the name implies, systematic reviews usually include a thorough and comprehensive plan and search strategy derived a priori to minimise bias by finding, evaluating, and synthesising all related studies on a given subject. A meta-analysis aspect is often used in systematic reviews, which entails using statistical techniques to synthesise data from several studies into a single quantitative estimation or summary effect size. It is a well-known and well-respected multinational non- profit organisation that promotes, funds, and disseminates systematic reviews and meta-analyses on the effectiveness of healthcare interventions (2) . II. NEED OF SYSTEMIC REVIEW AND META- ANALYSIS There are several reasons for performing a systematic review and meta-analysis:  It may assist in resolving discrepancies in results published by individual studies that may include bias or errors.  It may help identify areas in a field where there is a lack of evidence and areas where further research should be conducted.  It allows the combination of findings from different studies, highlighting new findings relevant to practice or policy.  It may be able to reduce the need for additional trials.  Writing a systematic review and meta-analysis will help identify a researcher's field of interest since they are published in high-impact journals and receive many citations many citations (3) . III. PHASES TO PLANNING A SYSTEMATIC REVIEW AND META-ANALYSIS The succeeding components to a successful systematic review and meta-analysis writing are:  Formulate the Review Question The first stage involves describing the review topic, formulating hypotheses, and developing a title for the review. It's usually best to keep titles as short and descriptive as possible by following this formula: Intervention for those with a disease (e.g., Dialectical behaviour therapy for adolescent females with a borderline personality disorder). Since reviews published in other outlets do not need to be listed as such, they should state in the title that they are a systematic review and meta-analysis.  Define inclusion and exclusion criteria The PICO (or PICOC) acronym stands for population, intervention, comparison, outcomes (and context). It can help ensure that all main components are decided upon before beginning the study. Authors must, for example, choose their population age range, circumstances, results, and type(s) of interventions and control groups a priori. It's also crucial to determine what types of experiments to include and exclude (e.g., RCTs only, RCTs and quasi- experimental designs, qualitative research), the minimum number of participants in each group, published and unpublished studies, and language restrictions.
  • 2. Copyright © 2021 pubrica. All rights reserved 2  Develop a search strategy and locate studies This is where a reference librarian can be particularly beneficial in assisting with the creation and execution of electronic searches. To recognise all applicable trials in a given region, it is essential to create a detailed list of key terms (i.e., "MeSH" terms) related to each component of PICOC. The secret to creating an effective search strategy is to strike a balance between sensitivity and precision.  Selection of studies After retrieving and reviewing a detailed list of abstracts, any studies that tend to satisfy inclusion requirements will be collected and thoroughly reviewed. To ensure inter-raterreliability, this procedure is usually carried out by at least two reviewers. It is suggested that authors maintain a list of all checked research, including reasons for inclusion or exclusion. It might be possible to hire study authors to collect missing data for data pooling (e.g., means, standard deviations). It's also possible that translations will be needed.  Extract data To organise the information extracted from each reviewed study (e.g., authors, publication year, number of participants, age range, study design, results, included/excluded), building and using a basic data extraction type or chart can be beneficial. Data extraction by at least two reviewers is necessary to ensure inter-rater reliability and prevent data entry errors Table: 1 outline for systemic review and meta-analysis Background Objectives Review questions Types of patients, interventions, outcomes and studies Search strategy Databases, study period, grey literature Review Methods Databases and article sources Screening Data extraction Assessment of data quality Data analysis References
  • 3. Copyright © 2021 pubrica. All rights reserved 3  Assess study quality In recent years, there has been a push to improve the consistency of each RCT included in systematic reviews. Double-blinding, which is acceptable for clinical trials but not for psychological or non- pharmacological treatments, significantly impacts this metric. Other more detailed guidelines and criteria, such as the Consolidated Standards of Reporting Trials (CONSORT), as well as articles with recommendations for improving quality in RCTs and meta-analyses for psychological intervention, are available(4) .  Analyse and Interpret results The Review Manager (RevMan) software, endorsed by the Cochrane Collaboration, is one example of a statistical programme that can measure effect sizes for meta-analysis. The effect sizes are given, along with a 95 percent confidence interval (CI) range, and are presented in both quantitative and graphical form (e.g., forest plots). Each trial is visually represented as a horizontal diamond shape in forest plots. The middle represents the effect size (e.g., SMD) and the endpoints representing both ends of the CI.  Disseminate findings Since the Cochrane Collaboration's reviews are published in the online Cochrane Database of Systematic Reviews, they are often lengthy and comprehensive. As a result, it is possible and encouraged to publish abbreviated versions of the review in other applicable scholarly journals; indeed, engaging in a review update or joining a well- established review team may be a beneficial way to get involved in the systematic review process. IV. FUTURE SCOPE The systematic review's findings should be discussed in terms of the strength of evidence and shortcomings of the initial research used for the review. It's also necessary to discuss the review's weaknesses, the results' applicability (generalizability), and the findings' implications for patient care, public health, and future clinical research (5) . V. CONCLUSION The steps of a systematic review/meta-analysis include developing a research question and validating it, forming criteria, searching databases, importing all results to a library and exporting to an excel sheet, protocol writing and registration, title and abstract screening, full-text screening, manual searching, extracting data and assessing its quality, data checking, and conducting statistics. The PRISMA or Meta-analysis must be used to write up the systematic study and meta-analysis. This is a reporting checklist for systematic literature reviews and meta-analyses that specifies what information should be included in each portion of a high-quality systematic review (6) . REFERENCES 1. Alonso Debreczeni, Felicia, and Phoebe E. Bailey. "A systematic review and meta-analysis of subjective age and the association with cognition, subjective well-being, and depression." The Journals of Gerontology: Series B 76.3 (2021): 471-482. 2. Vasconcellos, Diego, et al. "Self-determination theory applied to physical education: A systematic review and meta-analysis." Journal of Educational Psychology 112.7 (2020): 1444. 3. Geary, William L., et al. "Predator responses to fire: A global systematic review and meta‐ analysis." Journal of Animal Ecology 89.4 (2020): 955-971. 4. Donald, James N., et al. "Mindfulness and its association with varied types of motivation: A systematic review and meta-analysis using self- determination theory." Personality and Social Psychology Bulletin 46.7 (2020): 1121-1138. 5. Madigan, Sheri, et al. "Associations between screen use and child language skills: A systematic review and meta-analysis." JAMA paediatrics 174.7 (2020): 665-675. 6. McArthur, Genevieve M., et al. "Self-concept in poor readers: a systematic review and meta- analysis." PeerJ 8 (2020): e8772.