Robert has reviewed a number of studies that have manipulated the type of injuries a person receives as a result of a drunk driving accident. he then statistically combines the results from all studies to reach a general conclusion of the effect of type of injuries received. robert has most likely conducted a :

Meta - analysis

Explanation:

Meta analysis is a type of quantitative, epidemiological formal statistical analysis or study which can be used to combine data from previous multiple studies that has been carried out and draw out more precise and accurate conclusion(s) about a particular treatment.

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