Patient self-assessment in discriminating the more obstructed side in nasal breathing D CHIN 1,2 , J MALEK 3 , E PRATT 3 , G MARCELLS 4,5 , R SACKS 3,6-8 , R J HARVEY 3,6,9 1 Department of Otolaryngology, Head, Neck and Skull Base Surgery, St Vincent’s Hospital, Sydney, 2 Department of Otolaryngology, Head & Neck Surgery, Changi General Hospital, Singapore, 3 Faculty of Medicine, University of Sydney, 4 Bondi Junction Private Hospital, Sydney, 5 Department of Otolaryngology, Sydney Hospital, 6 Australian School of Advanced Medicine, Macquarie University, Sydney, 7 Department of Otolaryngology, Head and Neck Surgery, Concord General Hospital, Sydney, 8 Department of Otolaryngology, Macquarie University Hospital, Sydney, and 9 Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia Abstract Background: Correlating patient perception of nasal obstruction sidedness to causative anatomy is important in surgical planning. The accuracy of patient-perceived asymmetry of nasal obstruction, as regards objective measures, is described. Methods: Cross-sectional study of patients undergoing nasal airflow assessment. Unilateral obstruction was assessed using visual analogue scale scores and anterior rhinomanometry, without decongestion. Subjective obstruction asymmetry was defined using either the absolute score difference (right vs left) or the minimal clinically important difference, derived statistically. Correlation between subjective and objective obstruction measures was assessed. Results: In 145 patients (mean age ± standard deviation, 42.8 ± 16.6 years; 54.5 per cent female), objective obstruction was right-sided in 32.4 per cent, left-sided in 36.6 per cent and symmetrical in 31.0 per cent. Subjective perception of obstruction sidedness had a sensitivity and specificity of 86.9 and 41.1 per cent, respectively, using the minimal clinically important difference. Positive predictive value was 59.4 per cent using absolute score difference and 53.7 per cent using minimal clinically important difference. Receiver operator characteristic curve analysis indicated correlation between subjective and objective measures ( p < 0.001). Conclusion: Subjective perception of nasal obstruction asymmetry has limited accuracy. Corroboration with objective airway assessment may be helpful in patients whose symptoms are incongruous with clinical findings. Key words: Nasal Obstruction; Nasal Septum; Rhinomanometry; Nasal Surgical Procedures; Turbinates Background Correlating patients’ perceptions of asymmetrical nasal obstruction with their objective contributory anatomical factors is important before surgical intervention. Managing a patient whose assessment of asymmetry does not match their clinical findings can be challenging. Rhinomanometry can provide reliable and objective information about nasal airflow. Hirschberg and Rezek demonstrated a correlation between subjective assess- ment of nasal obstruction and objectively measured unilateral nasal airway resistance, and found that sub- jective reporting of the more obstructed side had a specificity of 84 per cent. 1 Additionally, a patient’s ability to identify the more obstructed side was better in those with pathological as compared with normal nasal resistance. 2 It was also better when the airflow difference between the two sides was larger relative to total airflow: when the difference in airflow was greater than 100 cm 3 /second, the sensitivity of subjec- tive assessment was 95 per cent. 3 While rhinomanometry is a good objective measure, it is affected by changes in the nasal cycle. Repeated measures in the same nostril need to account for such intrinsic variability. True asymmetry in unilateral nasal airway resistance may be better defined by only including cases in which the difference between sides is greater than the intrinsic variability. The latter can be estimated from the co-efficient of variation of unilat- eral nasal airway resistance, which has been reported to be up to 15 –17 per cent. 4,5 Presented as a poster at the 2012 Annual Scientific Meeting, Australian Society of Otolaryngology Head and Neck Surgery, 30 March to 3 April 2012, Adelaide, South Australia, Australia, and the 15th Asian Research Symposium in Rhinology (2012), 25–26 May 2012, Singapore. Accepted for publication 30 April 2013 The Journal of Laryngology & Otology, 1 of 6. MAIN ARTICLE © JLO (1984) Limited, 2013 doi:10.1017/S0022215113001631