'Template for protocol to be converted to review'

Review information

Authors

Finola M Delamere1, Diane Horsley1, Tina Leonard2, Jo Leonardi-Bee3

1Centre of Evidence-Based Dermatology, Cochrane Skin Group, The University of Nottingham, Nottingham, UK
2Centre of Evidence-Based Dermatology, Cochrane Skin Group, Nottingham University, Nottingham, UK
3Division of Epidemiology and Public Health, The University of Nottingham, Nottingham, UK

Citation example: Delamere FM, Horsley D, Leonard T, Leonardi-Bee J. 'Template for protocol to be converted to review'. Cochrane Database of Systematic Reviews [Year], Issue [Issue].

Contact person

Finola M Delamere

Centre of Evidence-Based Dermatology
Cochrane Skin Group, The University of Nottingham
Room A103, King's Meadow Campus
Lenton Lane
Nottingham
NG7 2NR
UK

E-mail: finola.delamere@nottingham.ac.uk

Dates

Assessed as Up-to-date:27 March 2008
Date of Search:08 February 2008
Next Stage Expected:01 January 2009
Protocol First Published:Not specified
Review First Published:Not specified
Last Citation Issue:Not specified

What's new

Date / EventDescription
19 March 2008
Amended

Converted to new review format.

History

Date / EventDescription
08 September 2004
New citation: conclusions changed

Substantive amendment

Abstract

Background

This should be one or two sentences to explain the context or elaborate on the purpose and rationale of the review. If this version of the review is an update of an earlier one, it is helpful to include a sentence such as “This is an update of a Cochrane review first published in YEAR, and previously updated in YEAR”.

Objectives

This should be a precise statement of the primary objective of the review, ideally in a single sentence, matching the Objectives in the main text of the review. Where possible the style should be of the form “To assess the effects of  [intervention or comparison] for [health problem] for/in [types of people, disease or problem and setting if specified]”.

Search methods

This should list the sources and the dates of the last search, for each source, using the active form ‘We searched.’ or, if there is only one author, the passive form can be used, for example, ‘Database X, Y, Z were searched’. Search terms should not be listed here. If the CRG’s Specialized Register was used, this should be listed first in the form ‘Cochrane X Group Specialized Register’. The order for listing other databases should be the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, other databases. The date range of the search for each database should be given. For the Cochrane Central Register of Controlled Trials this should be in the form ‘Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 1)’. For most other databases such as MEDLINE, it should be in the form ‘MEDLINE (January 1966 to December 2006)’. Searching of bibliographies for relevant citations can be covered in a generic phrase ‘reference lists of articles’. If there were any constraints based on language or publication status, these should be listed. If individuals or organizations were contacted to locate studies this should be noted and it is preferable to use ‘We contacted pharmaceutical companies’ rather than a listing of all the pharmaceutical companies contacted. If journals were specifically handsearched for the review, this should be noted but handsearching to help build the Specialized Register of the CRG should not be listed.

Selection criteria

These should be given as ‘[type of study] of [type of intervention or comparison] in [disease, problem or type of people]‘. Outcomes should only be listed here if the review was restricted to specific outcomes.

Data collection and analysis

This should be restricted to how data were extracted and assessed, and not include details of what data were extracted. This section should cover whether data extraction and assessments of risk of bias were done by more than one person. If the authors contacted investigators to obtain missing information, this should be noted here. What steps, if any, were taken to identify adverse effects should be noted.

Results

This section should begin with the total number of studies and participants included in the review, and brief details pertinent to the interpretation of the results (for example, the risk of bias in the studies overall or a comment on the comparability of the studies, if appropriate). It should address the primary objective and be restricted to the main qualitative and quantitative results (generally including not more than six key results). The outcomes included should be selected on the basis of which are most likely to help someone making a decision about whether or not to use a particular intervention. Adverse effects should be included if these are covered in the review. If necessary, the number of studies and participants contributing to the separate outcomes should be noted, along with concerns over quality of evidence specific to these outcomes. The results should be expressed narratively as well as quantitatively if the numerical results are not clear or intuitive (such as those from a standardized mean differences analysis). The summary statistics in the abstract should be the same as those selected as the defaults for the review, and should be presented in a standard way, such as ‘odds ratio 2.31 (95% confidence interval 1.13 to 3.45)’. Ideally, risks of events (percentage) or averages (for continuous data) should be reported for both comparison groups. If overall results are not calculated in the review, a qualitative assessment or a description of the range and pattern of the results can be given. However, ‘vote counts’ in which the numbers of ‘positive’ and ‘negative’ studies are reported should be avoided.

Authors' conclusions

The primary purpose of the review should be to present information, rather than to offer advice or recommendations. The Authors’ conclusions should be succinct and drawn directly from the findings of the review so that they directly and obviously reflect the main results. Assumptions should generally not be made about practice circumstances, values, preferences, tradeoffs; and the giving of advice or recommendations should generally be avoided. Any important limitations of data and analyses should be noted. Important conclusions about the implications for research should be included if these are not obvious.

Plain language summary

Template for protocol to be converted to review

 


Plain language title

The first part of a plain language summary is a restatement of the review’s title using plain language terms. It should include participants and intervention (and outcome, when included in the title of the review). As an example, a review title of ‘Anticholinergic drugs versus other medications for overactive bladder syndrome in adults’ might have a plain language title ‘Drugs for overactive bladder syndrome’. Where the review title is easily understood, this should simply be restated as the plain language title, e.g. ‘Interventions to reduce harm from continued tobacco use’.

The plain language title should not be declarative (it should not reflect the conclusions of the review). It should be written in sentence case (i.e. with a capital at the beginning of the title and for names, but the remainder in lower case; see examples above), should not be more than 256 characters in length, and should not end with a full stop.

Summary text
The second part, or body, of the plain language summary should be no more than 400 words in length and should include:

A statement about why the review is important: for example definition of and background to the healthcare problem, signs and symptoms, prevalence, description of the intervention and the rationale for its use.

The main findings of the review: this could include numerical summaries when the review has reported results in numerical form, but these should be given in a general and easily understood format. Results in the plain language summary should not be presented any differently from in the review (i.e. no new results should appear in the summary). Where possible an indication of the number of trials and participants on which the findings are based should be provided.

A comment on any adverse effects.

A brief comment on any limitations of the review (for example trials in very specific populations or poor methods of included trials).

At the end of the plain language summary authors may give web links (for example to other information or decision aids on CRG web sites, providing that these comply with The Cochrane Collaboration policy on web links. Graphs or pictures should not be included in the plain language summary. As with other components of a Cochrane review, plain language summaries should follow the format of the Cochrane Style Guide (available from www.cochrane.org/style).

 

Background

The text of the Background section of the review will be as it was written for the protocol, preferably using the following headinds

Description of the condition

As in the protocol

Description of the intervention

As in the protocol

How the intervention might work

As in the protocol

Why it is important to do this review

As in the protocol

Objectives

The text of the Objectives section of the review will be as it was written for the protocol

Methods

Criteria for considering studies for this review

Types of studies

Eligible study designs should be stated here, along with any thresholds for inclusion based on the conduct of the studies or their risk of bias. For example, ‘All randomized controlled comparisons’ or ‘All randomized controlled trials with blind assessment of outcome’. Exclusion of particular types of randomized studies (for example, cross-over trials) should be justified.

See also

  •  Eligibility criteria for types of study designs are discussed in Chapter 5 (Section 5.5).

Types of participants

The diseases or conditions of interest should be described here, including any restrictions such as diagnoses, age groups and settings. Subgroup analyses should not be listed here (see ‘Subgroup analysis and investigation of heterogeneity’ under ‘Methods’).

See also

  • Eligibility criteria for types of participants are discussed in Chapter 5 (Section 5.2).

Types of interventions

Experimental and comparator interventions should be defined here, under separate subheadings if appropriate. It should be made clear which comparisons are of interest. Restrictions on dose, frequency, intensity or duration should be stated. Subgroup analyses should not be listed here (see ‘Subgroup analysis and investigation of heterogeneity’ under ‘Methods’).

See also

  • Eligibility criteria for types of interventions are discussed in Chapter 5 (Section 5.3).

Types of outcome measures

Note that outcome measures do not always form part of the criteria for including studies in a review. If they do not, then this should be made clear. Outcome measures of interest should be listed in this section whether or not they form part of the eligibility criteria.

See also

  • Types of outcomes are discussed in Chapter 5 (Section 5.4).

Primary outcomes

Primary outcomes for the review should be identified from among the main outcomes. Primary outcomes are the outcomes that would be expected to be analysed should the review identify relevant studies, and conclusions about the effects of the interventions under review will be based largely on these outcomes. There should in general be no more than three primary outcomes and they should include at least one desirable and at least one undesirable outcome (to assess beneficial and adverse effects respectively).

Secondary outcomes

Main outcomes not selected as primary outcomes would be expected to be listed as secondary outcomes. In addition, secondary outcomes may include a limited number of additional outcomes the review intends to address. These may be specific to only some comparisons in the review. For example, laboratory tests and other surrogate measures may not be considered as main outcomes as they are less important than clinical endpoints in informing decisions, but they may be helpful in explaining effect or determining intervention integrity (see Chapter 7, Section 7.3.4).

The following optional (level 4) headings may be helpful, as supplements or replacements for the headings above:

Main outcomes for ‘Summary of findings’ table
Timing of outcome assessment

The timings for the outcomes should be stated, preferably using the following categories; short term, medium term and longer term. The primary timing should be highlighted.

Adverse outcomes
Economic data

Search methods for identification of studies

The methods used to identify studies should be summarized. The following headings are recommended. Before starting to develop this section, authors should contact their Cochrane Review Group (CRG) for guidance.

See also

  •  Search methods are discussed in detail in Chapter 6 (Sections 6.3)

Electronic searches

The bibliographic databases searched, the dates and periods searched and any constraints, such as language should be stated. The full search strategies for each database should be listed in an appendix to the review. If a CRG has developed a specialized register of studies and this is searched for the review, a standard description of this register can be referred to but information should be included on when and how the specialized register was most recently searched for the current version of the review and the search terms used should be listed.

See also

  • Search strategies are discussed in detail in Chapter 6 (Section 6.4).

Searching other resources

List grey literature sources, such as internal reports and conference proceedings. If journals are specifically handsearched for the review, this should be noted but handsearching done by the authors to help build the specialized register of the CRG should not be listed because this is covered in the standardized description of the register. List people (e.g. trialists or topic specialists) and organizations who were contacted. List any other sources used, which may include, for example, reference lists, the World Wide Web or personal collections of articles.

The following optional headings may be used, either in place of ‘Searching other resources’ (in which case they would be level 3 headings) or as subheadings (level 4).

Grey literature
List any theses that you have searched for reports of trials

Handsearching
Record any handsearching you have done in addition to that done on your behalf by the Cochrane Skin Group -which will be given to you as part of the search of the Cochrane Skin Group Specialised Register.

Note: To check which journals/years/conference proceedings have been handsearched by the CSG see http://www.mrw.interscience.wiley.com/cochrane/clabout/articles/SKIN/frame.html and scroll down to 'Specialised Register'

Reference lists
State whether you have searched the bibliographies of the included/excluded studies for reports of trials

Correspondence
State whether you have contacted authors/ pharmaceutical companies

See also 

  •  Other search resources are discussed in Chapter 6 (Section 6.2).

Data collection and analysis

The Methods section in a review should be written in the past tense, and should describe what was done to obtain the results and conclusions of the current version of the review. Often a review is unable to implement all of the methods outlined in the protocol, usually because there is insufficient evidence. In such circumstances, it is recommended that the methods that were not implemented still be outlined in the review, so that it serves as a protocol for future updates of the review.

Selection of studies

The method used to apply the selection criteria. Whether they are applied independently by more than one author should be stated, along with how any disagreements are resolved.

See also

  • Study selection is discussed in Chapter 7 (Section 7.2).

Data extraction and management

The method used to extract or obtain data from published reports or from the original researchers (for example, using a data collection form). Whether data are extracted independently by more than one author should be stated, along with how any disagreements are resolved. If relevant, methods for processing data in preparation for analysis should be described.

See also

  • Data collection is discussed in Chapter 7, including which data to collect (Section 7.3), sources of data (Section 7.4), data collection forms (Section 7.5) and extracting data from reports (Section 7.6)

Assessment of risk of bias in included studies

The method used to assess risk of bias (or methodological quality). Whether methods are applied independently by more than one author should be stated, along with how any disagreements are resolved. The tool(s) used should be described or referenced, with an indication of how the results are incorporated into the interpretation of the results.

See also

  • The recommended tool for doing so is described in Chapter 8 (Section 8.5).

Measures of treatment effect

The effect measures of choice should be stated. For example, odds ratio (OR), risk ratio (RR) or risk difference (RD) for dichotomous data; difference in means (MD) or standardized difference in means (SMD) for continuous data.

For dichotomous outcomes, it is preferable to use the risk ratio as a measure of treatment effect if the primary outcomes in either treatment group is likely to commonly occur (>20%), this is because the odds ratio tends to give a biased result is this circumstance. The risk difference should not be used as the sole measure of treatment effect for the primary outcome measures since it only gives an absolute measure of effect (the difference in the risk of the event between the treatment groups) which depends on the underlying risk of events.

The following optional headings may be used, either in place of ‘Measures of treatment effect’ (in which case they would be level 3 headings) or as subheadings (level 4):

Dichotomous data

Continuous data

Time-to-event data

See also

  • Types of data and effect measures are discussed in Chapter 9 (Section 9.2).

Unit of analysis issues

Special issues in the analysis of studies with non-standard designs, such as cross-over trials and cluster-randomized trials, should be described. Alternatively, optional (level 3) headings specific to the types of studies may be used, such as:

Cluster-randomised trials

Cross-over trials

Studies with multiple treatment groups

See also

  • Unit of analysis issues are discussed in Chapter 9 (Section 9.3).

Dealing with missing data

Strategies for dealing with missing data should be described. This will principally include missing participants due to drop-out (and whether an intention-to-treat analysis will be conducted), and missing statistics (such as standard deviations or correlation coefficients).

See also

  • Issues relevant to missing data are discussed in Chapter 16 (Sections 16.1) and intention-to-treat issues in Chapter 16 (Section 16.2).

Assessment of heterogeneity

Approaches to addressing clinical heterogeneity should be described, along with how the authors will determine whether a meta-analysis is considered appropriate. Methods for identifying statistical heterogeneity should be stated (e.g. visually or using the I2 test).

See also

  • Assessment of heterogeneity is discussed in Chapter 9 (Section 9.5)

Assessment of reporting biases

This section should describe how publication bias and other reporting biases are addressed (for example, funnel plots, statistical tests, imputation). Authors should remember that asymmetric funnel plots are not necessarily caused by publication bias (and that publication bias does not necessarily cause asymmetry in a funnel plot).

See also

  •  Reporting biases are discussed in Chapter 10.

Data synthesis

The choice of meta-analysis method should be stated, including whether a fixed-effect or a random-effects model is used. Authors are advised to use a random effect model to account for moderate levels of statistical heterogeneity. If a fixed effect model is chosen then a statement of justification is needed. If meta-analyses are not undertaken, systematic approaches to synthesizing the findings of multiple studies should be described.

See also

  • Meta-analysis and data synthesis are discussed in Chapter 9 (Section 9.4).

Subgroup analysis and investigation of heterogeneity

All planned subgroup analyses should be listed (or independent variables for meta-regression). Any other methods for investigating heterogeneity of effects should be described.

See also

  • Investigating heterogeneity is discussed in Chapter 9 (Section 9.6).

Sensitivity analysis

This should describe analyses aimed at determining whether conclusions are robust to decisions made during the review process, such as inclusion/exclusion of particular studies from a meta-analysis, imputing missing data or choice of a method for analysis.

See also

  • Sensitivity analysis is discussed in Chapter 9 (Section 9.7).

Results

Description of studies

Results of the search

The results sections should start with a summary of the results of the search (for example, how many references were retrieved by the electronic searches, and how many were considered as potentially eligible after screening).

See also

  • Presentation of search findings is discussed in Chapter 6 (Section 6.6).

Included studies

It is essential that the number of included studies is clearly stated. This section should comprise a succinct summary of the information contained in the ‘Characteristics of included studies’ table. An explicit reference to this table should be included. Key characteristics of the included studies should be described, including the study participants, location (e.g. country), setting (if important), interventions, comparisons and outcome measures in the included studies and any important differences among the studies. The sex and age range of participants should be stated here except where their nature is obvious (for example, if all the participants are pregnant). Important details of specific interventions used should be provided (for radiotherapy, for example, this might summarize the total dose, the number of fractions and type of radiation used; for drugs, this might summarize preparation, route of administration, dose and frequency). Authors should note any other characteristics of the studies that they regard as important for readers of the review to know. The following optional (level 4) subheadings may be helpful:

Design

Sample sizes

Setting

Participants

Interventions

Outcomes

See also

  • The ‘Characteristics of included studies’ table (Section 4.6.1).

Excluded studies

This should refer to the information contained in the ‘Characteristics of excluded studies’ table. An explicit reference to this table should be included. A succinct summary of why studies were excluded from the review should be provided.

See also

  • The ‘Characteristics of excluded studies’ table (Section 4.6.3).

The following optional (level 3) headings may be used in the ‘Description of studies’ section:

Ongoing studies

Studies awaiting classification

New studies found at this update

Risk of bias in included studies

This should summarize the general risk of bias in results of the included studies, its variability across studies and any important flaws in individual studies. The criteria that were used to assess the risk of bias should be described or referenced under ‘Methods’ and not here. How each study was rated on each criterion should be reported in a ‘risk of bias’ table and not described in detail in the text, which should be a concise summary.

See also

  • Presentation of ‘risk of bias’ assessments is addressed in Chapter 8 (Section 8.6).

Allocation

A summary of how allocation sequences were generated, and attempts to conceal allocation of intervention assignment and should be summarized briefly here, along with any judgements concerning the risk of bias that may arise from the methods used.

Blinding

A brief summary of who was blinded or masked during the conduct and analysis of the studies should be reported here. Implications of blinding of outcome assessment may be different for different outcomes, so these may need to be addressed separately. Judgements concerning the risk of bias associated with blinding should be summarized.

Incomplete outcome data

The completeness of data should be summarized briefly here for each of the main outcomes. Concerns of the review authors over exclusion of participants and excessive (or differential) drop-out should be reported.

Selective reporting

Concerns over the selective availability of data may be summarized briefly here, including evidence of selective reporting of outcomes, time-points, subgroups or analyses.

Other potential sources of bias

Any other potential concerns should be summarized here.

Effects of interventions

This should be a summary of the main findings on the effects of the interventions studied in the review. The section should directly address the objectives of the review rather than list the findings of the included studies in turn. The results of individual studies, and any statistical summary of these, should be included in ‘Data and analysis’ tables. Outcomes should normally be addressed in the order in which they are listed under ‘Types of outcome measures’. Subheadings are encouraged if they make understanding easier (for example, for each different participant group, comparison or outcome measure if a review addresses more than one). Any sensitivity analyses that were undertaken should be reported. Authors should include the relevant Comparison figure number (forest plot) in the subheading of the corresponding result section (for example Comparison 01/01).

 Authors should avoid making inferences in this section. A common mistake to avoid (both in describing the results and in drawing conclusions) is the confusion of ‘no evidence of an effect’ with ‘evidence of no effect’. When there is inconclusive evidence, it is wrong to claim that it shows that an intervention has ‘no effect’ or is ‘no different’ from the control intervention. In this situation, it is safer to report the data, with a confidence interval, as being compatible with either a reduction or an increase in the outcome.

See also

  • Presentation of results is addressed in Chapter 11 (Section 11.7).

Discussion

A structured discussion can aid the consideration of the implications of the review.

See also

  •  Interpretation of results is discussed in Chapter 12.

Summary of main results

Summarize the main findings (without repeating the ‘Effects of interventions’ section) and outstanding uncertainties, balancing important benefits against important harms. Refer explicitly to any ‘Summary of findings’ tables.

Overall completeness and applicability of evidence

Describe the relevance of the evidence to the review question. This should lead to an overall judgement of the external validity of the review. Are the studies identified sufficient to address all of the objectives of the review? Have all relevant types of participants, interventions and outcomes been investigated? Comments on how the results of the review fit into the context of current practice might be included here, although authors should bear in mind that current practice might vary internationally.

Quality of the evidence

Does the body of evidence identified allow a robust conclusion regarding the objective(s) of the review? Summarize the amount of evidence that has been included (numbers of studies, numbers of participants), state key methodological limitations of the studies, and reiterate the consistency or inconsistency of their results. This should lead to an overall judgement of the internal validity of the results of the review.

Potential biases in the review process

State the strengths and limitations of the review with regard to preventing bias. These may be factors within, or outside, the control of the review authors. The discussion might include the likelihood that all relevant studies were identified, whether all relevant data could be obtained, or whether the methods used (for example, searching, study selection, data collection, analysis) could have introduced bias.

Agreements and disagreements with other studies or reviews

Comments on how the included studies fit into the context of other evidence might be included here, stating clearly whether the other evidence was systematically reviewed.

Authors' conclusions

Implications for practice

The implications for practice should be as practical and unambiguous as possible. They should not go beyond the evidence that was reviewed and be justifiable by the data presented in the review. ‘No evidence of effect’ should not be confused with ‘evidence of no effect’.

Implications for research

This section of Cochrane reviews is used increasingly often by people making decisions about future research, and authors should try to write something that will be useful for this purpose. As with the ‘Implications for practice’, the content should be based on the available evidence and should avoid the use of information that was not included or discussed within the review.

 

In preparing this section, authors should consider the different aspects of research, perhaps using types of study, participant, intervention and outcome as a framework. Implications for how research might be done and reported should be distinguished from what future research should be done. For example, the need for randomized trials rather than other types of study, for better descriptions of studies in the particular topic of the review, or for the routine collection of specific outcomes, should be distinguished from the lack of a continuing need for a comparison with placebo if there is an effective and appropriate active treatment, or for the need for comparisons of specific named interventions, or for research in specific types of people.

 

It is important that this section is as clear and explicit as possible. General statements that contain little or no specific information, such as “Future research should be better conducted” or “More research is needed” are of little use to people making decisions, and should be avoided.

See also

  • Guidance on formulating conclusions is provided in Chapter 12 (Section 12.7).

Acknowledgements

This section should be used to acknowledge any individuals or organisations that the authors wish to acknowledge including individuals who are not listed among the authors. This would include any previous authors of the Cochrane review and might include the contributions of the editorial team of the CRG. Permission should be obtained from persons acknowledged.

Contributions of authors

The contributions of the current co-authors to the protocol or review should be described in this section. One author should be identified as the guarantor of the review. All authors should discuss and agree on their respective descriptions of contribution before the review is submitted for publication on the CDSR. When the review is updated, this section should be checked and revised as necessary to ensure that it is accurate and up to date.

  • See Chapter 4.5.1 in the handbook (www.cochrane-handbook.org)

Declarations of interest

Authors should report any present or past affiliations or other involvement in any organization or entity with an interest in the review that might lead to a real or perceived conflict of interest. Situations that might be perceived by others as being capable of influencing a review author’s judgements include personal, political, academic and other possible conflicts, as well as financial conflicts. Authors must state if they have been involved in a study included in the review.

See also

  • A summary of the Collaboration’s policy on conflicts of interest appears in Chapter 2 (Section 2.6).

Differences between protocol and review

It is sometimes necessary to use different methods from those described in the original protocol. This could be because:

  •  Methods for dealing with a particular issue had not been specified in the protocol;

Published notes

Published notes will appear in the review in the CDSR. They may include editorial notes and comments from the CRG, for example where issues highlighted by editors or referees are believed worthy of publication alongside the review. The author or source of these comments should be specified (e.g. from an editor or a referee).

Published notes must be completed for all withdrawn protocols and reviews, giving the reason for withdrawal. Only basic citation information, sources of support and published notes are published for withdrawn protocols and reviews.

Characteristics of studies

Characteristics of included studies

Footnotes

METHODS
D: design
AC: method of allocation concealment
RS: method of generating randomisation sequence
B: blinding (participant, clinician, outcome assessment)

Add definitions of any other abbreviations used.

Characteristics of excluded studies

Footnotes

Characteristics of studies awaiting classification

Footnotes

Characteristics of ongoing studies

Footnotes

Summary of findings tables

Additional tables

References to studies

Included studies

Excluded studies

Studies awaiting classification

Ongoing studies

Other references

Additional references

Other published versions of this review

Classification pending references

Data and analyses

Figures

Sources of support

Internal sources

External sources

Feedback

Appendices