What parameter generally determines the acceptable range for quality control results?

The acceptable range for quality control results is typically determined by the 95% confidence interval for the mean. This interval represents the range within which we would expect 95% of the data points to fall if the process is stable and the data are normally distributed. Establishing quality control limits using the 95% confidence interval helps to ensure that the majority of results generated by the process remain within expected boundaries, thereby acting as a reliable indicator of the performance of analytical methods.

One way to achieve this is by calculating the mean and standard deviation of a set of quality control measurements. The 95% confidence interval can then be derived from these parameters, generally defined as the mean plus or minus two standard deviations from the mean. This approach reflects a statistically robust method of monitoring whether the tests and procedures are functioning as intended, allowing for timely detection of any deviations or errors.

The other options do not accurately capture the determined statistical basis for quality control ranges utilized in clinical chemistry. For instance, while the range that includes 50% of the results might sound reasonable, it does not provide sufficient information to assess the overall variability and reliability of test results as effectively as the 95% confidence interval would. Similarly, the central 68% of results aligns more