LOE 1 | Quality assessment for Randomized Controlled Trials |
The seven factors included as the relevant quality items for RCTs are: | |
· Was the assignment of patients to treatment randomized? | |
· Was the randomization list concealed? | |
· Were all patients who entered the trial accounted for at its conclusion? | |
· Were the patients analyzed in the groups to which they were randomized? | |
· Were patients and clinicians "blinded" to which treatment was being received? | |
· Aside from the experimental treatment, were the groups treated equally? | |
· Were the groups similar at the start of the trial? | |
Quality assessment for meta-analyses of RCTs | |
The six factors included as the relevant quality items for meta-analyses are: | |
· Were specific objectives of the review stated (based on a specific clinical question in which patient, intervention, comparator, outcome (PICO) were specified) | |
· Was study design defined? | |
· Were selection criteria stated for studies to be included (based on trial design and methodological quality)? | |
· Were inclusive searches undertaken (using appropriately crafted search strategies)? | |
· Were characteristics and methodological quality of each trial identified? | |
· Were selection criteria applied and a log of excluded studies with reasons for exclusion reported? | |
LOE 2 | Quality assessment for studies using concurrent controls without true randomization |
The four factors included as the relevant quality items for these studies are: | |
· Were comparison groups clearly defined? | |
· Were outcomes measured in the same (preferably blinded), objective way in both groups? | |
· Were known confounders identified and appropriately controlled for? | |
· Was follow-up of patients sufficiently long and complete? | |
Quality assessment for meta-analyses of studies using concurrent controls without true randomization | |
The six factors included as the relevant quality items for meta-analyses are: | |
· Were specific objectives of the review stated (based on a specific clinical question in which patient, intervention, comparator, outcome (PICO) were specified) | |
· Was study design defined? | |
· Were selection criteria stated for studies to be included (based on trial design and methodological quality)? | |
· Were inclusive searches undertaken (using appropriately crafted search strategies)? | |
· Were characteristics and methodological quality of each trial identified? | |
· Were selection criteria applied and a log of excluded studies with reasons for exclusion reported? | |
LOE 3 | Quality assessment for studies using retrospective controls: |
The four factors included as the relevant quality items for these studies are: | |
· Were comparison groups clearly defined? | |
· Were outcomes measured in the same (preferably blinded), objective way in both groups? | |
· Were known confounders identified and appropriately controlled for? | |
· Was follow-up of patients sufficiently long and complete? | |
LOE 4 | Quality assessment for case series |
The three factors included as the relevant quality items for these studies are: | |
· Were outcomes measured in an objective way? | |
· Were known confounders identified and appropriately controlled for? | |
· Was follow-up of patients sufficiently long and complete? | |
LOE 5 | Quality assessment for studies that are not directly related to the specific patient/population |
LOE 5 studies are those not directly related to the specific patient/population (e.g. different patient/population, animal models, mechanical models etc.), and should have their methodological quality allocated to the methodology of the study. The relevant quality criteria here are: | |
· Good = randomized controlled trials (equivalent of LOE 1) | |
· Fair = studies without randomized controls (equivalent of LOE 2–3) | |
· Poor = studies without controls (equivalent of LOE 4). |