A National e-Survey of Adult Reference Intervals of Routine Chemistry Analytes Used by Laboratories Across Pakistan: A Step Towards Harmonization.

Objectives: To identify the variation of reference intervals, reporting units used for key blood chemistry parameters in laboratories across Pakistan and to understand the factors contributing to these discrepancies. Methodology: A comprehensive e-questionnaire developed using google forms covering key blood chemistry parameters (Electrolytes, fasting glucose, glucose random urea, creatinine and lipid profile), reference intervals, reporting units, and laboratory practices was administered via email to the Pathologists. Frequency and percentages were calculated for each response and descriptive results were also evaluated. Result: A total of 38 responses were received five responses were excluded due to incomplete forms. The responses from 33 laboratories revealed substantial variability in reference intervals (RIs) for routine blood chemistry parameters, underscoring a significant lack of standardization. 66.66% laboratories had not developed specific RIs, relying instead on manufacturer-provided RIs, with infrequent reviews or updates. Challenges were prevalent due to non-harmonized RIs, leading to patient and physician counseling issues. Primary obstacles included funding deficiencies and limited access to healthy samples. Conclusion: These findings emphasize the critical need for national regulatory guidelines to standardize RIs, thereby enhancing the reliability and accuracy of laboratory diagnostics in Pakistan.