Critical result thresholds and notification practices in clinical laboratories.

Laboratory medicine plays an important role in clinical decision-making. The timely notification of results requiring medical attention is therefore essential to ensure patient safety. Since its introduction, the concept of critical result notification has expanded to include both critical decision limits and significant abnormal results. To avoid overlooking such results, most laboratories use alert lists consisting of predefined thresholds programmed into the laboratory information system. Despite widespread adoption, considerable variability persists in alert lists used across laboratories. Differences in patient populations and healthcare settings partly explain variation in alert thresholds, acceptable notification delays, communication modalities, and the designated recipients of notifications. Telephone communication remains the predominant modality for notifying critical results, although electronic medical record-based alerts are increasingly being implemented. Persistent challenges include notification fatigue, communication delays, and inconsistent follow-up actions. Quality indicators should therefore address not only the timeliness of notification but also the timeliness of the clinical response. Looking ahead, the integration of structured clinical and laboratory data, together with emerging artificial intelligence tools, holds promise for developing more personalized and clinically meaningful notification policies.