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how you will attempt to avoid duplicate publication bias and state how multiple reports and if publications of the same study will be assembled and compared for duplication, completeness and possible contradictions. Please note in this section if you will use RevMan to manage data storage and analysis. If you intend to use alternative software you must discuss this with the CPHG, and note your intention in the protocol. Resources Cochrane Handbook – Chapter 7 Chapter 21 in Cochrane Handbook on Reviews in Health Promotion and Public Health (www.cochrane-handbook.org) Refer to Cochrane Health Equity website for information on assessing issues relevant to equity, along with a checklist for authors that can be used and submitted along with the draft protocol (http://equity.cochrane.org) Assessment of risk of bias in included studies In this section, you should provide an adequate description of the tool(s) you will use to assess the risk of bias of included studies. You should also describe how the tool(s) will be implemented and the criteria used to assign studies, for example, to judgements of low risk, high risk and unclear risk of bias. The risk of bias assessment must be conducted in duplicate with a clear process for resolving disagreements. Supporting information to justify all risk of bias judgements must be included in the risk of bias tables. You can consider including the source of the information, for example, direct quotes from the study paper. If you are only including randomised controlled trials, we recommend that you use the Cochrane Collaboration’s Risk of Bias (RoB) tool. This includes selection bias, performance bias, attrition bias, detection bias and reporting bias. With regard to the assessment of blinding, we recommend that you consider separately the risk of bias due to lack of blinding for (i) participants and study personnel (performance bias) and (ii) outcome assessment (detection bias). It is also often appropriate to consider the risk of bias due to lack of blinding separately for different types of outcomes. When assessing attrition bias, it is recommended to consider the impact of missing data separately for different outcomes. If you are including non-randomised studies we recommend you use the Effective Practice and Organisation of Care (EPOC) RoB Tool for studies with a separate control group instead. This can be used for randomised controlled trials as well as controlled before and after studies and other nonrandomised designs that include a control group (with the exception of interrupted time series studies). This tool includes the standard Cochrane RoB tool items as well as an additional item to consider the likelihood of contamination. Importantly for nonrandomised studies, it also includes additional items to assess the risk of selection bias and subsequent confounding (“were baseline outcome measurements similar?” and “were baseline characteristics similar?”). We recommend supplementing this with another additional item, ”did the study authors appropriately adjust for important confounders in their analysis?”. Last updated: 24 November 2011 - 12 -
If you are including ITS studies we recommend that you assess the risk of bias of these studies using the EPOC RoB tool for ITS study designs which includes four items from the Cochrane 'Risk of bias' tool to assess performance, attrition, detection and reporting bias as well as the following additional items relevant for ITS studies: “was the intervention independent of other changes?”, “was the shape of the intervention effect pre-specified?” and “was the intervention unlikely to affect data collection?”. Both of the EPOC RoB tools mentioned above can be found on the EPOC website: http://epocoslo.cochrane.org/sites/epocoslo.cochrane.org/files/uploads/Suggested%20risk%20o f%20bias%20criteria%20for%20EPOC%20reviews.doc as well as guidance for how to prepare a RoB table: http://epocoslo.cochrane.org/sites/epocoslo.cochrane.org/files/uploads/How%20to%20prepare %20a%20risk%20of%20bias%20table%20for%20reviews%20that%20include%20more%20than%2 0one%20study%20design.doc. Note that for some items in the RoB tool, for example blinding, it may make sense to provide a different assessment for different outcomes (for example outcome assessors may be blinded for some outcome measures and not others, or some measures may be more objective/subjective than others). Where appropriate, add additional items into the RoB table to allow for this. Alternative approaches should be discussed and agreed with your contact editor. See Appendix 3 for general information on Risk of bias tables (referenced from the Cochrane Handbook). This is an area of methodological development and any new tools will be available on the CPHG website. In this section you also need to describe the method by which you will summarise the risk of bias assessments. Rather than at the study level, it is recommended that you do this at the outcome level. This is due to the fact that the risk of bias may be different for different outcomes within the same study. To do this you can provide an overall risk of bias assessment for the main outcomes within each study, then provide an overall risk of bias assessment for relevant outcomes across studies, so that outcomes will be judged overall as ‘Low’, ‘Medium’ or ‘High’ risk of bias given overall considerations of the study designs, and the potential impact of the identified risks noted in the table for each study that contributed results for that outcome. Also, consider how you will address risk of bias in the synthesis of your results, considering how potential study biases might affect your conclusions. Measures of treatment effect In this section you should state how outcomes will be reported (e.g. dichotomous data) and how you will analyse and compare them (e.g. using Risk Ratios). It is likely that a number of quantitative outcome measures may be identified. You need to firstly identity the types of data you will obtain from your included study designs. For controlled studies, with continuous data, we recommend reporting means or changes in mean scores. Weighted mean difference can also be reported for continuous outcomes. Standardised mean differences should be reported when different studies use different scales to report the same outcome (e.g. quality of life scales). Where a number of outcome measures are identified, authors should use the ratio of means method (Friedrich 2008). Dichotomous (or binary) outcomes can expressed as relative risks (RR), odds ratio (OR) or risk difference (RD), however the CPHG recommends using RR (Deeks 2002). We also recommend using RR for categorical data (e.g. outcomes reported on a short Likert Last updated: 24 November 2011 - 13 -
Page 1 and 2: The Cochrane Public Health Group Gu
Page 3 and 4: Getting started Now that your title
Page 5 and 6: interventions for enhancing access
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Page 9 and 10: Chapter 21 in Cochrane Handbook on
Page 11: published elsewhere. These addition
Page 15 and 16: Handbook which outlines the options
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Page 21 and 22: Appendix 1 - Guidance for establish
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Page 27 and 28: Was the study adequately protected
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