A secure assay device is disclosed herein that provides: an assay or a test device that provides at least one result, wherein the assay or test device comprises at least one surface which exhibits optical change in response to at least one target particle, at least one marker or a combination thereof; and at least one multi-layer coating that at least partially covers the assay membrane, the assay device or a combination thereof, wherein the multi-layer coating blocks or impairs the user visualization of the optical change, the at least one result or a combination thereof. A secure reader and method of utilizing the secure assay device and secure reader are disclosed herein.