Paediatric Barcelona Olfactory Test-6 (pBOT-6): Validation of a Combined Odour Identification and Threshold Screening Test in Healthy Spanish Children and Adolescents

BACKGROUND AND OBJECTIVES: Few odour tests have been created for children. Objectives: The aim of the present study was to develop and validate a simple and quick olfactory test, suitable for the evaluation of odour identification and threshold in a Spanish paediatric population, the paediatric Barcelona Olfactory Test-6 (pBOT-6). METHODS: The pBOT-6 consisted in a set of 6 odorants for a forced-choice identification test (IT), and a 6 dilutions phenyl ethyl alcohol geometric series for the threshold test (TT). The pBOT-6 was compared with the U-sniff test (a validated international paediatric smell test) in 131 Spanish healthy volunteers aged 6-17 years. A Bland-Altman plot was used to determine the agreement between two tests. Reliability was analyzed in fifteenvolunteers using the intraclass correlation coefficient (ICC). Normative data was obtained and 8 children diagnosed with subjective smell loss were tested for validation. RESULTS: Bland-Altman analysis demonstrated a minimal bias of -1.71% with upper and lower limit of agreement of -31.1% and 27.6%, respectively. The ICC was 0.83 (95% CI 0.6-0.96) for the IT and 0.73 (95% CI 0.36-0.9) for the TT, showing excellent and good consistency between measurements over time. Mean pBOT-6 scores were significantly higher in healthy volunteers compared with patients with smell loss. Discrimination between normosmia and smell loss was achieved with a sensitivity of 96.9% and a specificity of 100%. CONCLUSIONS: The pBOT-6 offers an effectiveand fast method useful in clinical routine to distinguish, with high sensitivity and specificity, between paediatric patients with normosmia and those with smell dysfunction.