Typical Steps Taken When a Control
Is Outside Acceptable Range*
Laboratory Operations Review 54
STEP RATIONALE
Hold patient results until problem is resolved.Rerun control (1 time only).If control is still out, run a new vial of control or another lot #.If control is still out, look for & correct any problems, then
run control.If control is still out, recalibrate, then run control.If control is still out, get assistance.Once resolved, document corrective action.Evaluate all patient results in rejected run & since last run
with acceptable QC. Repeat tests & issue corrected reports,
as needed.*Follow laboratory’s written protocol.
If a control value is inaccurate, patient values might be inaccurate.Value might have been due to expected random error. (1 in 20 results
will be outside ±2 SD.)Control might have been outdated, improperly stored, contaminated.Consider reagents (low, outdated, improperly stored, contaminated,
change in lot #), preventive maintenance (overdue), mechanical problems,
clots, etc.Calibration may have shifted.Supervisor or service rep may be able to determine problem.Provides a record for future reference, points out repetitive problems.Ensure accuracy of reported results.