Impact of a Limitation Section on the Meta-analysis Results' Interpretation

Study Overview
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Brief Summary
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Objective: The investigators aim to evaluate the impact of a  limitations  section in systematic review's abstract on results' interpretation by readers. Design: Randomized ratio 1:1 controlled trial with two parallel arms. Participants will be invited to participate in an online survey. Participants: Eligible participants are corresponding authors of randomized controlled trial published between 2010 and 2012 and referenced in pubmed Intervention: The investigators will evaluate the impact of the presence of a  limitations  section in abstract of systematic review with meta-analysis. The investigators selected abstracts of meta-analysis published in the journal Annals of Internal Medicine between 2006 and 2011. Selected abstract will be standardised and the treatment's name hidden. The two groups of abstract will be presented as follow: 1) abstract with  limitations  section and 2) abstract without  limitations  section: the  limitations  section of the original abstract will be deleted. Selected participants are invited by e-mail to answer the survey. After reading one abstract from his group a randomization they are invited two answer 5 questions about their interpretation of the meta-analysis's results.

Detailed Description
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OBJECTIVE The aim of the study is to evaluate the impact of a  limitations  section in systematic review's abstract on results' interpretation by readers. STUDY DESIGN The study is a randomized controlled trial with two parallel arms. The study follows the CONSORT 2010 statements Participant will be invited to participate in an on-line survey with a secured web site. Participants, after a characteristic description will be randomized in one of the two arms: 1) abstract with a  limitations  section 2) abstract without a  limitations  section. ELIGIBILITY Eligible participants are corresponding authors of randomized trials published between 2010 and 2012 and referenced in pubmed core set journal INTERVENTION We will evaluate the impact of the presence of a  limitations  section in abstract of systematic review with meta-analysis. SELECTION OF ABSTRACTS We will retrieve all systematic review with meta-analysis published in the journals Annals of Internal Medicine between the years 2006 and 2012, about health care intervention with a conclusion in favor the experimental treatment or intervention. We exclude updates, diagnostical, genetical, epidemiological or economical evaluation and multiple or indirect comparisons. MODIFICATION OF ABSTRACTS All selected abstracts will be standardised. Treatment name will be replaced with experimental treatment A, control treatment will be replaced by control treatment B if necessary in the title and in the abstract. The two groups of abstract will be presented as follow: Abstract with  limitations  section Abstract without  limitations  section: the  limitations  section of the original abstract will be deleted. OUTCOMES PRIMARY OUTCOME The primary outcome will be, the readers' recommendation of the experimental treatment A SECONDARY OUTCOMES Secondary outcomes will evaluate the interpretation of the results of the meta-analysis. The readers will answers the following questions, with the choice of answers based on a 10-point Likert scale How would you rate the quality of the systematic review? How confident are you in the results of this systematic review? Do you consider that the experimental treatment A is a proven effective treatment? How confident are you in the validity of the conclusion that the authors draw? NUMBER OF PARTICIPANT A power analysis was conducted to estimate the number of subject (participants) needed to achieve a power of 0.9 and an alpha value of 0.05 to discern a different of effect size of 0.4 between the two versions of abstract. This resulted in an estimate to the need of recruit a minimum of 133 participants in each arm, either a total of 266 participants STATISTICAL ANALYSIS We will analyze data with R project software, in intention to treat. Data for quantitative variables are expressed with medians and interquartile (IQR) ranges. Qualitative variables are expressed with frequencies and percentages and missing data Primary analysis will compare means of the primary outcome between the 2 groups with a Student t test.

Official Title
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Impact of a Limitation Section on the Meta-analysis Results' Interpretation: a Randomized Controlled Trial

Conditions
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Systematic Review With Metaanalysis

Intervention / Treatment
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* Behavioral: interpretation of the abstract


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: abstract of meta-analysis published in the journal Annals of Internal Medicine between 2006 and 2012, about health care intervention with a conclusion in favour the experimental treatment Exclusion Criteria: updates of previously published systematic reviews, systematic review if diagnostic test accuracy, prognosis, epidemiologic, economics evaluation indirect comparison meta-analysis.
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: abstract without limitation section<br>the experimental arm is abstract without the limitation section | Behavioral: interpretation of the abstract<br>* the intervention consist to interpret the results of the meta-analysis after reading the abstract.<br>|
| Other: abstract with limitation section<br>the control arm is abstract with the original limitation section | Behavioral: interpretation of the abstract<br>* the intervention consist to interpret the results of the meta-analysis after reading the abstract.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| confidence in the results | we ask participants: how confident are you in the results of this systematic review? | 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| interpretation of the quality of the systematic review | We ask participants:  how would you rate the quality of the systematic review? how confident are you in the validity of the conclusion of the systematic review? how confident are you that intervention A is more beneficial than comparative intervention? how confident are you that the results of this systematic review could be apply in clinical practice? | 1 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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limitation, quality, bias, meta-analysis, interpretation, abstract