Boo AYY, Koh YLE, Hu PL, et al. - Given that serum potassium represents a component of routine laboratory examinations performed for patients with hypertension or diabetes mellitus in primary care, and haemolysis is known to result in false hyperkalaemia, therefore, researchers investigated the prevalence of unlysed false hyperkalaemia as well as the factors related to false-and-true-hyperkalaemia. This study was conducted in Singapore and involved all patients of any ethnicity aged ≥21 with serum potassium assessment done. Between August 2015 and August 2017, experts analyzed electronic health records of index patients with potassium > 5.5 mmol/L as well as its corresponding laboratory processing time in seven local polyclinics. In specimens with potassium ≥6.0 mmol/L vs those with potassium <5.1 mmol/L, the average processing time was identified to be 50 min longer. Estimated glomerular filtration rate (eGFR) and delayed laboratory processing time were reported as the risk factors significantly related to false hyperkalaemia. Findings demonstrated a prevalence of 86.4% for false hyperkalaemia. Patients with eGFR < 60ml/min/1.73m² may be targeted for recommendation to repeat potassium tests.