From: Trial Forge Guidance 2: how to decide if a further Study Within A Trial (SWAT) is needed
The five proposed criteria for deciding whether the intervention needs another evaluation in a SWAT. The more criteria that are met, the more likely we are to conclude that further evaluation in a SWAT is appropriate. | |
1. GRADE: the GRADE [22] certainty in the evidence for all key outcomes is lower than ‘high’.a | |
2. Cumulated evidence: the cumulative meta-analysis shows that the effect estimate for each outcome essential to make an informed decision has not converged.b,c | |
3. Context: the range of host trial contexts evaluated to date does not translate easily to the context of the proposed SWAT.d For the proposed SWAT consider PICOT [23]: | |
• P – is the population in the host trial so different from those already included that the current evidence does not provide sufficient certainty? | |
• I – are the health interventions in the host trial so different from those already included that the current evidence does not provide sufficient certainty? | |
• C – is the comparator in the host trial so different from those already included that the current evidence does not provide sufficient certainty? | |
• O – is the SWAT outcome(s) so different to those used in the existing evaluations that that the current evidence does not provide sufficient certainty? | |
• T – in the time since the existing evaluations were done, have regulatory, technological or societal changes made those evaluations less relevant? | |
4. Balance – participants: the balance of benefit and disadvantage to participants in the host trial and/or the SWAT is not clear.e | |
5. Balance – host trial: the balance of benefit and disadvantage to the new host trial is not clear.f |