Have a look at the following terms and see if you know what they mean. Then check your answers below.
Accuracy - An accurate measurement method is one that gives the measurer the correct value or very close to it. An unreliable method cannot possibly be accurate. Consistency also does not guarantee accuracy. Accuracy allows groups to be compared and results to be statistically tested.
Example: When a thermometre is incorrectly calibrated. It might yield highly consistent readings on an interval scale, but they are all inaccurate because the initial calibration method was incorrect.
Reliability - The same measurement leads to the same results and thereby demonstrates the consistency of the results.
Example: If you were carrying out diet trials, the results would clearly show if one diet was always outperforming the other diet or if there were times when the results were inconsistent.
Validity - Determines whether the observation recorded measures what is required.
Example: If you were carrying out diet trials to determine the performance of each, the measurements that would reveal this information would be the length, weight and FCR.
