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Results

[fixed, level 1 heading]

Description of studies

[fixed, level 2 heading]

Results of the search

[recommended, level 3 heading]

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).  Review authors are strongly encouraged to include a study flow diagram as recommended by the PRISMA statement (Liberati 2009). Such flow diagrams can be created within RevMan 5.1.

See also

 

Included studies

[recommended, level 3 heading]

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

 

Excluded studies

[recommended, level 3 heading]

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 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

[fixed, level 2 heading]

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

For large reviews, aspects of the assessment of risk of bias may be summarized for the primary outcomes under the following headings.

 

Allocation

[recommended, level 3 heading]

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

 

Blinding

[recommended, level 3 heading]

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

[recommended, level 3 heading]

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

[recommended, level 3 heading]

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

[recommended, level 3 heading]

Any other potential concerns should be summarized here.

 

Effects of interventions

[fixed, level 2 heading]

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 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