normotensives and and fidelity of hypertensives). implementation of interventions. Broad criteria used to critically appraise each study: generalizability to the population of interest and methodological appropriateness (ie risk of bias) Bias The risk of bias Risk of bias Risk of bias was Risk of bias was Risk of bias was Risk of bias evaluation assessment assessment conducted assessed for each assessed for each assessed for each considered as part of included considered: on each study and study using the study using the study using the criteria used to -allocation included an Cochrane Risk of Cochrane Handbook Cochrane Handbook critically appraise concealment: assessment of the Bias tool (included for Systematic for Systematic studies. classified as being quality of the recording of Reviews of Reviews of For RCTs, bias allocation allocation, blinding, Interventions. The Interventions. The evaluation ‘adequate’ (participants and concealment, which incomplete outcome assessment assessment considered: blinding, investigators could was ranked as being data and selective considered: considered: method of not foresee adequate, unclear or reporting) - randomisation - randomisation (for randomisation, size allocation), inadequate - allocation RCTs only) and characteristics of ‘unclear’ (randomisation used concealment - For cohort studies, study population, but not sufficiently - blinding information was drop-out rate and described) or - management of collected on potential relevance of sodium incomplete outcome sources of bias in intake level. ‘inadequate’ (participants or data non-randomised For observational investigators could - selective reporting studies, including: studies, bias foresee allocation) bias characteristics of the evaluation - Blinding: blinding - other sources of sample, the considered: of investigator, bias (eg. similarity of intervention and its design, length, participant and groups at baseline) implementation, the method of measuring outcome assessor completeness of sodium intake and noted follow-up, and the adjustment for methods used in the confounders
normotensives and hypertensives). and fidelity of implementation of interventions. Broad criteria used to critically appraise each study: generalizability to the population of interest and methodological appropriateness (ie risk of bias) Bias evaluation included The risk of bias assessment considered: -allocation concealment: classified as being ‘adequate’ (participants and investigators could not foresee allocation), ‘unclear’ (randomisation used but not sufficiently described) or ‘inadequate’ (participants or investigators could foresee allocation) - Blinding: blinding of investigator, participant and outcome assessor noted Risk of bias assessment conducted on each study and included an assessment of the quality of the allocation concealment, which was ranked as being adequate, unclear or inadequate Risk of bias was assessed for each study using the Cochrane Risk of Bias tool (included recording of allocation, blinding, incomplete outcome data and selective reporting) Risk of bias was assessed for each study using the Cochrane Handbook for Systematic Reviews of Interventions. The assessment considered: - randomisation - allocation concealment - blinding - management of incomplete outcome data - selective reporting bias - other sources of bias (eg. similarity of groups at baseline) Risk of bias was assessed for each study using the Cochrane Handbook for Systematic Reviews of Interventions. The assessment considered: - randomisation (for RCTs only) - For cohort studies, information was collected on potential sources of bias in non-randomised studies, including: characteristics of the sample, the intervention and its implementation, the completeness of follow-up, and the methods used in the Risk of bias considered as part of criteria used to critically appraise studies. For RCTs, bias evaluation considered: blinding, method of randomisation, size and characteristics of study population, drop-out rate and relevance of sodium intake level. For observational studies, bias evaluation considered: design, length, method of measuring sodium intake and adjustment for confounders