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© 2018 JTECH Medical MN065_N
INTAKE
EVALUATE
ANALYZE
REPORT
Conventions Used Throughout This Manual
The following conventions are used in the manual to describe the devices, and operation:
• Calibration - The process of using a known force or angle to adjust the device parameters so that any
arbitrary force or angle input can be accurately determined.
• CV - The coefficient of variation (CV) is defined as the ratio of the standard deviation (σ) to the mean (μ), or
in mathematical terms, CV = σ / μ. In probability theory and statistics, CV serves as a normalized measure
of variability to help describe the relative scatter or spread of a data sample. A smaller CV suggests a higher
level of consistency. A calculated CV less than 15% (0.15) is often used as an indicator of consistent effort by
subjects during biometric strength tests.
The Northstar software calculates CV using population standard deviation. Note that this differs from CV
calculated using the sample standard deviation, which can give a very different result.
• Device - This refers to a JTECH Medical testing device, used in conjunction with the Northstar software to
record test data.
• Exam - This term is used to refer to a group of tests performed with the same device.
• Repetition, or Rep - A single instance of measuring performance for a designated device.
• RF - Radio Frequency.
• ROM - Range of Motion.
• Side - Either left or right, noted as L and R, respectively.
• Test - Used to refer to a group of repetitions performed for one or more sides with a given device.
• Threshold - The minimum force or angle that must be exceeded to start or end a repetition. This is also the
minimum force or angle that can be reached before the repetition ends.
• Zero or Zero Calibration or Set Zero - The process of determining the device parameters when no force or
angle is applied to the device.
