An inventory system configured for reducing variability in detecting and counting surgical items, the inventory system comprising: an RFID tag affixed to a surgical item, the RFID tag configured to transmit a return signal when energized; a signal generator configured to generate an energizing signal for the RFID tag; an antenna operably coupled to the signal generator, the antenna configured to receive the return signal transmitted by the RFID tag; a sensor configured to generate a signal indicative of a spatial parameter of the antenna when scanning for the RFID tag; a processor; and a memory, including instructions stored thereon, which when executed by the processor cause the system to: scan, using the antenna, for the RFID tag; sense, by the sensor, the signal indicative of a spatial parameter of the antenna over a period of time; and provide an indication that the spatial parameter of the antenna over time meets a predetermined rule wherein the sensor includes at least one of a proximity sensor, a gyro, an accelerometer, a laser sensor, or a sensor configured to detect an electronic marker wherein the sensor is further configured to interpret motion wherein the instructions, when executed by the processor, further cause the system to: determine if the antenna was moved in a predetermined scanning pattern based on the sensed spatial parameter over the period of time; and provide an indication that the antenna was moved in the predetermined scanning pattern based on the determination. an RFID tag affixed to a surgical item, the RFID tag configured to transmit a return signal when energized; a signal generator configured to generate an energizing signal for the RFID tag; an antenna operably coupled to the signal generator, the antenna configured to receive the return signal transmitted by the RFID tag; a sensor configured to generate a signal indicative of a spatial parameter of the antenna when scanning for the RFID tag; a processor; and a memory, including instructions stored thereon, which when executed by the processor cause the system to: scan, using the antenna, for the RFID tag; sense, by the sensor, the signal indicative of a spatial parameter of the antenna over a period of time; and provide an indication that the spatial parameter of the antenna over time meets a predetermined rule wherein the sensor includes at least one of a proximity sensor, a gyro, an accelerometer, a laser sensor, or a sensor configured to detect an electronic marker wherein the sensor is further configured to interpret motion wherein the instructions, when executed by the processor, further cause the system to: scan, using the antenna, for the RFID tag; sense, by the sensor, the signal indicative of a spatial parameter of the antenna over a period of time; and provide an indication that the spatial parameter of the antenna over time meets a predetermined rule wherein the sensor includes at least one of a proximity sensor, a gyro, an accelerometer, a laser sensor, or a sensor configured to detect an electronic marker wherein the sensor is further configured to interpret motion wherein the instructions, when executed by the processor, further cause the system to: determine if the antenna was moved in a predetermined scanning pattern based on the sensed spatial parameter over the period of time; and provide an indication that the antenna was moved in the predetermined scanning pattern based on the determination.