Hello everyone, I have a question for what other places do to fullfill the CAP Hem 25870 stating: If commercially assayed controls are used for CBC instruments, control values correspond to the methodology and target values (mean and QC ranges) are verified or established by the laboratory. Note: most commercial controls have expected recovery ranges for each parameter, provided by the manufacturer. The mean of such ranges may not be the exact target value in a given laboratory. Each laboratory must assign its own initial target value, based on initial analysis of the material; this target value should fall within the recovery range supplied by the manufacturer, but need not exactly match the package insert mean. The lab must establish specific recovery ranges that accommodate known changes in product attributes, assuming the calibration has not changes. Do you guys tighten the ranges? Make your SD smaller so the range is smaller? The package insert range is usually quite wide and if it is tighter problems from trends and shifts can be seen sooner. I have tightned ours, but it seems it maybe too much? Thanks for the help!