To evaluate and compare the analytical performance of Revvity's PlGF and sFlt-1 assays against Roche methods in diagnosing preeclampsia.
Approach:
Assay Evaluation: The Revvity assays for PlGF and sFlt-1 were compared to Roche methods through imprecision studies and paired analytical comparisons.
Statistical Analysis: Data were evaluated for numeric agreement and concordance relative to manufacturer recommended thresholds for preeclampsia.
Key Findings:
Imprecision estimates for Revvity methods ranged from 3.2 to 9.0 CV%.
Median CV% for PlGF was 1.8% and for sFlt-1 was 1.1% based on clinical specimens.
Overall Passing-Bablok regression for PlGF was y = −23.4 + 0.73x (r = 0.983) and for sFlt-1 was y = −87.7 + 0.40x (r = 0.971).
Concordance of the sFlt-1:PlGF ratio relative to manufacturer thresholds was 95.2%.
Interpretation:
The Revvity methods for PlGF and sFlt-1 are precise and correlate with Roche methods.
Limitations:
Statistically significant concentration-dependent relative bias was observed for both methods, which may affect clinical interpretation.
Further research is needed to understand how method differences impact clinical outcomes.
Conclusion:
Manufacturer specific thresholds should be applied in clinical practice, and further research is needed to understand the implications of method differences.
