RADHIKa: Ratio-based analysis deriving basis for comparison of historical, parallel or interdependent reported ken of studies - a novel method for comparing interconnected and disconnected data sets

Ashish Indani, Srinivas Reddy Boreddy, Tushar Deshpande


Background: Control arm selection is difficult for devices clinical trial due to the complexity and uniqueness of every device.  Therefore, we propose RADHIKa - ratio-based analysis deriving basis for comparison of historical or parallel interdependent reported ken of studies that can be used to compare the relative performance or safety of independent studies.

Methods: A ken (set of studies) has four basic prerequisites to qualify for RADHIKa. Comparison and calculations are based upon assessment of two major factors, effect and influence. RADHIKa is a three step methodology that includes construction of ken, ratio calculations, and plotting box plots.

Results: Inferences of RADHIKa has ratio and box plot interpretation. When the RADHIKa ratio is 1 or close to 1, both the control arm and the evaluation arm are equal. The box plot indicates the tendency of the parameter along with the difference in two arms. When the dark box is above line of unity, it indicates that the evaluation arm has performed better or if it’s vice versa the predicate has performed better. The tails of the box indicate significance of the outcome in each direction.

Conclusions: RADHIKa method is a useful tool to compare the relative performance or safety of independent studies, especially single arm device studies.


Meta-analysis, Medical device clinical trials, Medical devices comparison, Statistics, Research methodology, Clinical evaluation medical devices, Substantial equivalence

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