Routine Capillary Hemoglobin Testing in United Kingdom Commercial Pilot Applicants.

Abstract

Introduction: United Kingdom regulations mandate hemoglobin (Hb) testing at each commercial (Class 1) pilot medical examination. The utility of point-of-care finger-prick capillary Hb in determining aeromedical certification outcomes remains unquantified.

Methods: A retrospective review was conducted of all initial Class 1 medical examinations recorded in the UK Civil Aviation Authority medical records system from April 2021 to March 2025. Applicants with capillary Hb outside thresholds (male <115 g · L-1, female <105 g · L-1, all >180 g · L-1) were identified. Clinical pathways, confirmatory testing, and fitness outcomes were analyzed.

Results: Of 3353 applicants, 48 (1.43%; 95% confidence interval 1.08-1.89) had abnormal capillary Hb (33 high, 15 low). Of those, 35 (73%) were certified fit, 1 (2%) was assessed as unfit due to predeclared sickle cell disease, and 12 (25%) were lost to follow-up prior to fitness determination. Only 3 of 36 applicants receiving a fitness outcome were assessed as unfit or required treatment before certification (positive predictive value 8.3%; 95% confidence interval 2.9-21.8%). Among 13 applicants undergoing confirmatory venous testing, 12 returned normal results. No cases of polycythemia were identified.

Discussion: Capillary Hb screening did not identify conditions leading to unfit assessment beyond predeclared disease. The sole unfit determination resulted from a disqualifying history before testing. Two applicants (0.06%) required treatment before certification; whether these would have been detected through clinical evaluation alone is uncertain. These findings suggest limited utility for this screening practice in asymptomatic initial pilot applicants, though value in serial assessments of established pilots warrants further investigation. MacMillan PP. Routine capillary hemoglobin testing in United Kingdom commercial pilot applicants. Aerosp Med Hum Perform. 2026; 97(8):601-606.