Title: What is a C2 Review Protocol?
1What is a C2 Review Protocol?
- Presented by
- Harris Cooper
- University of Missouri-Columbia
- Larry V. Hedges
- University of Chicago
2A Review Protocol is a document that
- Sets out the reviewers intentions with regard to
the topic and the methods to be used in carrying
out a proposed review - Is meant for inclusion in the Campbell Database
of Systematic Reviews
3How were the Guidelines for a C2 Review Protocol
Established?
4The C2 Protocol Guidelines were
- Drafted by the Methods Working Group at the
request of the Steering Committee using the
Cochrane Collaboration Protocol Guidelines and
other sources as guides - Reviewed (via e-mail) by attendees of the C2
Inaugural Meeting, sent to approximately 80
people, 7 of whom provided feedback - Reviewed by the Steering Committee
- Approved by the Steering Committee (December 22,
2000)
5Why are C2 Review Protocols Necessary?
- Preparing a review is a complex process that
comprises many judgments and decisions. - The methods to be used should be established
beforehand (to the extent possible) because - The studies to be included are usually identified
after they have been completed - The results of many of these studies may already
be known to the reviewers
6Why are C2 Review Protocols Necessary?
- Therefore, it is important to make the review
process as well-defined, systematic, and unbiased
as possible while maintaining a practical
perspective. - Requiring detailed protocols is one way to
- Allow the editorial referees to provide guidance
and advice - Prevent problems from occurring during the review
process - Ensure that final products will meet the
standards of the Campbell Collaboration
7What Should a C2 Protocol Contain?
8A protocol for a Campbell Review should consist
of the following sections
- Cover Sheet
- Background for the Review
- Objectives for the Review
9A protocol for a Campbell Review should consist
of the following sections
- Methods
- Criteria for inclusion and exclusion of studies
in the review - Search strategy for identification of relevant
studies - Description of methods used in the component
studies - Criteria for determination of independent
findings - Details of study coding categories
- Statistical procedures and conventions
- Treatment of qualitative research
10A protocol for a Campbell Review should consist
of the following sections
- Timeframe
- Plans for Updating the Review
- Acknowledgements
- Statement Concerning Conflict of Interest
- References
- Tables
11What Should a C2 Protocol Cover Sheet Contain?
12The cover sheet of the protocol should include
- The title of the review
- The names of the reviewers
- Contact information for the lead reviewer
- Sources of support
13What should a C2 Protocol Background Section
Contain?
14The background section of the protocol should
present
- An overview of the theoretical, conceptual,
and/or practical issues surrounding the research
problem - A general description of prior reviews, the
controversies these reviews have created or left
unresolved, and which of these will be the focus
of the new review effort
15The background section
- Sets out the context of an already formed body of
knowledge - Provides the rationale for the review
- Explains why the questions being asked are
important - Sets the stage for the empirical results that
follow
16The background section should contain
- A conceptual discussion of the research problem
- A brief overview of the research question
including its theoretical, practical, and
methodological history - The qualitative and historical debates
surrounding the research question - A discussion of previous reviews of the research
topic
17The background section should answer questions
such as
- From where does the problem, approach, and/or
intervention in the research come? - Do debates exist surrounding the meaning of the
problem or utility of the intervention? - Do theories predict how the major variables
involved in the review will be related to one
another? - Do different theories or philosophies of
treatment yield conflicting predictions?
18What Should a C2 Protocol Objectives Section
Contain?
- All Campbell Collaboration Reviews are undertaken
to gather, summarize and integrate empirical
research so as to help people understand the
evidence.
19Within this overarching framework, reviews can,
for example, be meant to
- Produce general statements about relationships
and treatment effects through the synthesis of
individual study results - Find reasons for conflicting evidence
- Explain variations in practice
20Within this overarching framework, reviews can,
for example, be meant to
- Answer questions, using variations in studies,
that could not have been answered in the
individual component studies - Review the evidence on the subjective experience
of an intervention - Build connections between related areas of
research
21In setting out the objectives, reviewers should
keep in mind that Campbell Reviews must
- Help people make practical decisions about social
behavioral interventions and public policy - Address the choices (practical options) people
face when deciding about whether or not to adopt
a policy or practice - Relate to outcomes that are meaningful to people
making decisions about public policy
22What should a C2 Methodology Section Contain?
- The methods section should describe operationally
how the review will be conducted.
23What should a C2 Methodology Section Contain?
- The methods sections of a C2 review will differ
considerably from that of a primary research
study.
24What should a C2 Methodology Section Contain?
- Most methods section will need to address several
separate issues - Criteria for inclusion and exclusion of studies
in the review - Search Strategy for identification of possibly
relevant studies - Description of methods used in primary research
25What should a C2 Methodology Section Contain?
- Criteria for determination of independent
findings - Details of study coding strategies
- Statistical procedures and conventions that may
be used - How qualitative research will be treated in the
review
26How should a C2 Protocol Address Questions of
Study Inclusion/Exclusion?
- The protocol should explain the criteria that
will be applied to determine relevance of studies
uncovered by the search. - It is critical that these criteria be explicated
in advance.
27How should a C2 Protocol Address Questions of
Study Inclusion/Exclusion?
- This section of the protocol should answer
question such as - What characteristics of studies will be used to
determine if a study was relevant to the topic of
interest? - What characteristics of studies will lead to
exclusion?
28How should a C2 Protocol Address Questions of
Study Inclusion/Exclusion?
- Will decisions be based on
- Report tile?
- Abstracts?
- Full Reports?
- Who will make the relevance decisions?
- How will reliability of relevance decisions be
assessed?
29How should a C2 Protocol Address Questions of
Study Inclusion/Exclusion?
- Examples of studies that would be included and
excluded should be given.
30How should a C2 Protocol Address Questions of
Study Inclusion/Exclusion?
- C2 reviews can include evidence from studies of
implementation. This evidence can derive from a
broad range of qualitative and quantitative
evidence.
31How Should a C2 Protocol Address Questions of
Search Strategy?
- Reviewers should present details of their search
strategy, such as - Reference databases used
- Hand searches of specific journals
- Personal contacts
32How Should a C2 Protocol Address Questions of
Search Strategy?
- It should also include a rationale for the search
strategy, bearing in mind that the ultimate goal
is to reduce the differences between the body of
retrieved studies and those that go undiscovered.
33How Should a C2 Protocol Address Questions of
Search Strategy?
- Reviewers need to report the keywords, years
searched, and search strategy used to guide the
search of reference databases and bibliographies.
34How Should a C2 Protocol Address Questions of
Search Strategy?
- Reviewers also need to indicate mechanisms they
will use to retrieve documents, especially
unpublished ones.
35How Should a C2 Protocol Address Questions of
Search Strategy?
- As far as possible, evidence considered should
not be restricted by nationality of investigators
or by language unless there is a good
justification to do so.
36How Should a C2 Protocol Address Descriptions of
Primary Research Methods
- The protocol should describe the methods most
commonly used in the primary research covered in
the review.
37How Should a C2 Protocol Address Descriptions of
Primary Research Methods
- This should focus more on designs actually
realized than on theory, e.g. - Participant sampling procedures
- Research designs
- Measurement methods
38How Should a C2 Protocol Address Descriptions of
Primary Research Methods
- Reviewers should identify a few studies that
illustrate the methods used in primary research
and present the details of these studies.
39How Should a C2 Protocol Address Criteria for
Determining Independence on Findings?
- Reviewers need to describe how they will handle
studies that produce multiple findings of
effectiveness based on the same data.
40How Should a C2 Protocol Address Criteria for
Determining Independence on Findings?
- This can happen when
- Several types of outcome are measured on the same
subjects - The same outcome is measured at several points in
time - Several treatment groups are compared to the same
control group - Several different studies (publications) use data
from the same people
41How Should a C2 Protocol Address Criteria for
Determining Independence on Findings?
- If more than one outcome is used from the same
study (or from different studies using the same
people) reviewers need to explain how they will
assure that the different outcomes will be
statistically independent.
42How should a C2 Protocol Describe Coding
Categories?
- Characteristics of studies that will be coded and
examined for potential use as moderators of study
outcomes should be described.
43How should a C2 Protocol Describe Coding
Categories?
- All retrieved characteristics should be
mentioned, even if they are not eventually used.
44How should a C2 Protocol Describe Coding
Categories?
- If some outcomes or moderators are excluded, a
rationale should be given for that exclusion.
45How should a C2 Protocol Describe Coding
Categories?
- Information about quality assurance of coding
(e.g., coding reliability assessment and
monitoring) should be included in this section.
46How Should a C2 Protocol Describe Statistical
Procedures?
- This section should describe the procedures and
conventions used to carry out the quantitative
analysis of results.
47How Should a C2 Protocol Describe Statistical
Procedures?
- It should explain
- The effect size measure used
- Any adjustments that are made to effect sizes to
reduce bias - The techniques that will be used to combine
evidence - How missing data will be handled
48How Should a C2 Protocol Describe Statistical
Procedures?
- How statistics describing the overall literature
will be presented - What techniques will be used to assess
variability of results - What techniques will be used to explain variation
in results - What sensitivity analyses will be carried out
49How Should a C2 Protocol Describe Statistical
Procedures?
- A rational for each of the choices above should
be given.
50How Should a C2 Protocol Describe Statistical
Procedures?
- If no quantitative synthesis will be carried out,
rationale should be given for the alternative
technique.
51How should a C2 Protocol Address Treatment of
Qualitative Research?
52Qualitative Studies Can Be Part of C2 Reviews
- Qualitative studies can assist in
- Defining interventions more precisely
- The choice of relevant outcome measure
- The development of valid research questions
- Interpretation heterogeneous results
53Qualitative Studies Can Be Part of C2 Reviews
- When a review contains relevant qualitative
research, reviewers should operationally describe
for qualitative studies - Criteria for inclusion and exclusion of
qualitative studies - Methods used in these primary research studies
- Criteria for determining independent findings
- Characteristics of included studies in the same
detail as they do for quantitative research.
54What Should a C2 Protocol Timeframe Contain?
55Examples of some benchmarks to be used in setting
targets are the anticipated dates for completion
of
- Searches for published and unpublished studies
- Pilot testing of inclusion criteria
- Relevance assessments
- Pilot testing of study codes and data collection
- Extraction of data from research reports
- Statistical Analysis
- Preparation of report
56What should a C2 Protocol Timeframe Contain?
- Reviewers together with the editors of their
Collaborative Review Group, must determine and
appropriate timeframe for a specific review. - Targets may vary widely from review to review
depending on its scope and complexity, as well as
the resources available.
57What Should a C2 Protocol Plan for Updating the
Review Contain?
58Updating Plans should include
- Specifications for how the review, once
completed, will be updated - Information on who will be responsible for
updates - The frequency with which updates can be expected
59What Should a C2 Protocol Acknowledgements
Section Contain?
- Acknowledgment should be made of all individuals
contributing to the preparation of the protocol
who were not listed on the cover sheet.
60What Should a C2 Protocol Statement Concerning
Conflict of Interest Contain?
- It is a matter of Campbell Collaboration policy
that direct funding from a single source with a
vested interest in the results of the review is
not acceptable.
61Reviewers should report any conflict of interest
capable of influencing their judgments including
- Personal
- Political
- Academic
- Financial
62Campbell Reviews should be free of any real or
perceived bias introduced by
- The receipt of any benefit in cash or kind
- Any hospitality
- Any subsidy derived from any source that may have
or be perceived to have an interest in the
outcome of the review - Financial conflicts of interest cause the most
concern. They can and should be avoided, but
must be reported if there are any.
63Campbell Reviews should be free of any real or
perceived bias
- It is impossible to abolish conflict of interest,
since the only person who does not have some
vested interest in a subject is somebody who
knows nothing about it.
64Campbell Reviews should be free of any real or
perceived bias
- Disclosing a conflict of interest does not
necessarily reduce the worth of a review and it
does not imply dishonesty.
65Campbell Reviews should be free of any real or
perceived bias
- Reviewers should include statements in their
protocol about potential conflicts even when they
are confident that their judgments will not be
influenced.
66Campbell Reviews should be free of any real or
perceived bias
- Editors may decide that disclosure is not
warranted or they may decide that readers should
know about such a conflict of interest so that
they can make up their own minds about how
important it is. - Decisions about whether or not to publish such
information should be made jointly by reviewers
and editors.
67What Should a C2 Protocol References Section
Contain?
- The protocol should include complete references
of all cited works. - References and other stylistic considerations
should follow the guidelines of the American
Psychological Association - American Psychological Association. (1994).
Publication Manual of the American Psychological
Association (4th Ed.). Washington, DC Author
68What Should a C2 Protocol Tables and Figures
Contain?
- Any tables and figures included in the protocol
should appear after the text.
69How is a C2 Protocol Registered?
- Once a proposed protocol has been completed it
should be sent to the appropriate Collaborative
Review Group editors.
70How is a C2 Protocol Registered?
- When the editors are satisfied that the protocol
meets the standards of the Campbell Collaboration
they will include it in the Review Groups module
for publication in the Campbell Database of
Systematic Reviews. - Publishing protocols may encourage interested
parties to contact the reviewers and may
discourage others from undertaking a review on
the same topic
71Editors and reviewers should not include a
protocol in a module unless there is a firm
commitment
- To complete the review within a reasonable
timeframe - To keep the review up-to-date once it is completed
72What Happens if the Approved C2 Protocol
Undergoes Changes?
- While every effort should be made to adhere to a
predetermined protocol, it is recognized that
this is not always possible or appropriate. - Changes in the protocol should not be made on the
basis of how they affect the results of the
review. - As a rule, when possible analyses should be
performed to show the effect of the change on the
results of the review.
73How should a C2 Protocol be cited?
- When the protocol is converted into a full
review, the fact that this review was preceded by
a published protocol should be noted.
74How should a C2 Protocol be cited?
- It is Campbell Collaboration policy that
protocols that have not been converted into full
reviews within - TWO YEARS
- will be withdrawn from the Campbell Database of
Systematic Reviews.
75What Other Sources of Assistance Can Help Develop
a C2 Protocol?
- In addition to the guidelines presented above,
prospective reviewers will find sound advice for
proposing and conducting Campbell Reviews in the
following works - Clark M. Oxman A. D. (Eds.).(2000). Cochrane
reviewers handbook Version 4.1. In Review
Manager (RevMan) Computer program. Version 4.1
Oxford, England The Cochrane Center. (Available
on-line at http//www.cochrane.org/cochrane/hbook
.htm ).
76What Other Sources of Assistance Can Help Develop
a C2 Protocol?
- In addition to the guidelines presented above,
prospective reviewers will find sound advice for
proposing and conducting Campbell Reviews in the
following works - Cooper, H. Hedges, L. V. (Eds.). (1994). The
handbook of research synthesis. New York Russell
Sage Foundation.
77What Other Sources of Assistance Can Help Develop
a C2 Protocol?
- In addition to the guidelines presented above,
prospective reviewers will find sound advice for
proposing and conducting Campbell Reviews in the
following works - National Health Service Centre for Reviews and
Dissemination. (2000). Undertaking systematic
reviews of research on effectiveness. York,
England University of York. (Available at
http//www.york.ac.uk/inst/crd/report4.htm ).
78What Other Sources of Assistance Can Help Develop
a C2 Protocol?
- Reviewers may contact the Campbell Secretariat
for further guidance in preparing Campbell Review
protocols.