A Procedure Used to Hide the Group Assignment from the Participants

question 33

Multiple Choice

A procedure used to hide the group assignment from the participants in a study to prevent their beliefs about the effectiveness of a treatment from affecting the results is ______.

• A) double-blind design
• B) tri-blind design
• C) multi-blind design
• D) single-blind design

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Definitions:

Aerodynamic Tractor-Trailer Rigs

Trucks designed with features that reduce air resistance, improving fuel efficiency and reducing operational costs.

Vehicle Braking

Refers to the various systems used to slow down or stop a vehicle.

Tractor-Trailer Semi-Combination Rig

A combination of a tractor unit and one or more trailers attached to it, commonly used for freight transport.

Supply Tanks

Containers used to store fluids or gases needed for the operation of machinery or vehicles, such as fuel or hydraulic fluid tanks.