| Standard criteria are used to assess the methodological quality of studies included in EPOC reviews (protection against bias). Each criterion is scored as DONE, NOT CLEAR, or NOT DONE. Details regarding the application of these criteria are available from the editorial base.
Seven standard criteria are used to assess the methodological quality of randomised controlled trials (RCTs) and controlled clinical trials (CCTs):
1. Concealment of allocation (protection against selection bias). This is scored as DONE if the unit of allocation was by institution, team or professional and any random process was described explicitly; or if the unit of allocation was by patient or episode of care and there was some form of centralised randomisation scheme, an on‐site computer system or sealed opaque envelopes were used.
2. Follow‐up of professionals (protection against exclusion bias). This is scored as DONE if outcome measures were obtained for 80% to 100% of subjects randomised.
3. Follow‐up of patients. This is scored as DONE if outcome measures were obtained for 80% to 100% of patients randomised, or for patients who entered the trial.
4. Blinded assessment of primary outcome(s) (protection against detection bias). This is scored as DONE if the authors state explicitly that the primary outcome variables were assessed blindly, or the outcome variables are objective, eg. length of hospital stay, drug levels as assessed by a standardised test. Primary outcome(s) are those variables that correspond to the primary hypothesis or question as defined by the authors. In the event that some of the primary outcome variables were assessed in a blind fashion and others were not, each is scored separately.
5. Baseline measurement. This is scored as DONE if performance or patient outcomes were measured prior to the intervention, and no substantial differences were present across trial groups.
6. Reliable primary outcome measure(s). This is scored as DONE if there were two or more raters with at least 90% agreement or kappa greater than or equal to 0.8 OR the outcome data were obtained from some automated system, eg. length of hospital stay, drug levels as assessed by a standardised test.
7. Protection against contamination. This is scored as DONE if allocation was by community, institution or practice and it is unlikely that the control group received the intervention. |
