The Buddhasothorn Asthma Severity Score (BASS): A practical screening tool for predicting severe asthma exacerbations for pediatric patients

Main Article Content

Suttipong Ittiporn
Kanlaya Prajongdee


acute asthma management, asthma exacerbation, emergency department, inhaled bronchodilator, severity score, Wood–Downes–Ferrés Scale


Background and aim: A precise scaling system of acute asthma leads to an accurate assessment of disease severity. This study aimed to compare the accuracy of the Buddhasothorn Asthma Severity Score (BASS) with the Wood–Downes–Ferrés Scale (WDFS) to recognize the severity level of acute asthma.

Materials and methods: A cross-sectional study was conducted comprising Thai children aged 2–15 years with acute asthma. The BASS and WFDS were rated once in the emergency department. The degree of severity was determined by frequency and type of nebulized bronchodilator administrations at the time of initial treatment. The optimum cutoff points for the area under the curve (AUC) were established to predict severe asthma exacerbations.

Results: All 73 episodes of asthma exacerbations (EAEs) in 35 participants were analyzed. Fifty-nine (80.8%) EAEs were classified as severe. Both scales had good significance to recognize the selection of nebulized bronchodilator treatments by AUC of 0.815 (95% Confidence Interval [CI]: 0.680–0.950) in case of BASS, and AUC of 0.822 (95% CI: 0.70–0.944) in case of WDFS. Cutoff points of BASS ≥ 8 had sensitivity 72.9%, specificity 64.3%, positive predictive value (PPV) 89.6%, negative predictive value (NPV) 36.0% at an AUC of 0.718 (95% CI: 0.563–0.873) for severe exacerbations. These results were consistent for cutoff points of WDFS ≥ 5 with sensitivity 78.0%, specificity 50.0%, PPV 86.8%, NPV 35.0% at an AUC of 0.768 (95% CI: 0.650–0.886) for predicting severe exacerbations. There was no significant difference between the AUCs of both scales.

Conclusions: Both the BASS and WDFS were good and accurate scales and effective screening tools for predicting severe asthma exacerbations in pediatric patients by optimal cutoff points.

Abstract 208 | PDF Downloads 170 HTML Downloads 20 XML Downloads 6


1. Bekhof J, Reimink R, Brand PL. Systematic review: Insufficient validation of clinical scores for the assessment of acute dyspnoea in wheezing children. Paediatr Respir Rev. 2014;15(1):98–112. 10.1016/j.prrv.2013.08.004

2. Wood DW, Downes JJ, Lecks HI. A clinical scoring system for the diagnosis of respiratory failure. Preliminary report on childhood status asthmaticus. Am J Dis Child. 1972;123(3): 227–8. 10.1001/archpedi.1972.02110090097011

3. Gorelick MH, Stevens MW, Schultz TR, Scribano PV. Performance of a novel clinical score, the Pediatric Asthma Severity Score (PASS), in the evaluation of acute asthma. Acad Emerg Med. 2004;11(1):10–8. 10.1197/j.aem.2003.07.01510.1111/j.1553-2712.2004.tb01365.x

4. Ducharme FM, Chalut D, Plotnick L, Savdie C, Kudirka D, Zhang X, et al. The Pediatric Respiratory Assessment Measure: A valid clinical score for assessing acute asthma severity from toddlers to teenagers. J Pediatr. 2008;152(4):476–80, 80.e1. 10.1016/j.jpeds.2007.08.034

5. Hsu P, Lam LT, Browne G. The Pulmonary Index Score as a clinical assessment tool for acute childhood asthma. Ann Allergy Asthma Immunol. 2010;105(6):425–9. 10.1016/j.anai.2010.10.009

6. Arnold DH, Gebretsadik T, Abramo TJ, Moons KG, Sheller JR, Hartert TV. The RAD score: A simple acute asthma severity score compares favorably to more complex scores. Ann Allergy Asthma Immunol. 2011;107(1):22–8. 10.1016/j.anai.2011.03.01

7. The Global Initiative for Asthma (GINA). Global strategy for asthma management and prevention [Internet]. [cited 2020 Jan 28]. Bethesda, MD: GINA; 2018. Available from: and-prevention/

8. Direkwattanachai C, Aksilp C, Chatchatee P, Jirapongsananuruk O, Kamalaporn H, Kamchaisatian W, et al. Practical considerations of nebulized corticosteroid in children with acute asthmatic exacerbation: A consensus. Asian Pac J Allergy Immunol. 2021;39(3):168–76.

9. Sarkar M, Madabhavi I, Niranjan N, Dogra M. Auscultation of the respiratory system. Ann Thorac Med. 2015;10(3):158–68. 10.4103/1817-1737.160831

10. Chacko J, King C, Harkness D, Messahel S, Grice J, Roe J, et al. Pediatric acute asthma scoring systems: A systematic review and survey of UK practice. J Am Coll Emerg Physicians Open. 2020;1(5):1000–8. 10.1002/emp2.12083

11. Grief SN. Upper respiratory infections. Prim Care. 2013;40(3): 757–70. 10.1016/j.pop.2013.06.004

12. Cao AM, Choy JP, Mohanakrishnan LN, Bain RF, van Driel ML. Chest radiographs for acute lower respiratory tract infections. Cochrane Database Syst Rev. 2013;2013(12):Cd009119. 10.1002/14651858.CD009119.pub2

13. Williams DM. Clinical pharmacology of corticosteroids. Respir Care. 2018;63(6):655–70. 10.4187/respcare.06314

14. Fábregas ML, de Diego Damiá A, Martínez Francés M, Cordero Rodríguez P, Perpiñá Tordera M. Relationship between peak expiratory flow and clinical exploration and arterial gas analysis in assessing the severity of an asthma attack. Arch Bronconeumol. 1996;32(1):4–9. 10.1016/S0300-2896(15)30830-9

15. Rivas-Juesas C, Rius Peris JM, García AL, Madramany AA, Peris MG, Álvarez LV, et al. A comparison of two clinical scores for bronchiolitis. A multicentre and prospective study conducted in hospitalised infants. Allergol Immunopathol (Madr). 2018;46(1):15–23. 10.1016/j.aller.2017.01.012

16. Vichyanond P, Veskitkul J, Rienmanee N, Pacharn P, Jirapong-sananuruk O, Visitsunthorn N. Development of the siriraj clinical asthma score. Asian Pac J Allergy Immunol. 2013;31(3):210–6.

17. Thaweerujirot C, Daengsuwan T. Comparison between pediatric respiratory assessment measure (PRAM) score and Wood’s asthma score to assess acute asthma exacerbation. Asian Pac J Allergy Immunol. 2019;37(3):123–9. 10.12932/AP-060118-0232

18. Dean P, Florin TA. Factors associated with pneumonia severity in children: A systematic review. J Pediatr Infect Dis Soc. 2018;7(4):323–34. 10.1093/jpids/piy046

19. Florin TA, Brokamp C, Mantyla R, DePaoli B, Ruddy R, Shah SS, et al. Validation of the Pediatric Infectious Diseases Society–Infectious Diseases Society of America severity criteria in children with community-acquired pneumonia. Clin Infect Dis. 2018;67(1):112–9. 10.1093/cid/ciy031

20. Harris M, Clark J, Coote N, Fletcher P, Harnden A, McKean M, et al. British Thoracic Society guidelines for the management of community acquired pneumonia in children: Update 2011. Thorax. 2011;66(Suppl 2):ii1–23. 10.1136/thoraxjnl-2011-200598

21. Principi N, Esposito S. Biomarkers in pediatric community--acquired pneumonia. Int J Mol Sci. 2017;18(2):447. 10.3390/ijms18020447

22. Chang AB, Clark R, Acworth JP, Petsky HL, Sloots TP. The impact of viral respiratory infection on the severity and recovery from an asthma exacerbation. Pediatr Infect Dis J. 2009;28(4): 290–4. 10.1097/INF.0b013e31819067b

23. Bishop J, Carlin J, Nolan T. Evaluation of the properties and reliability of a clinical severity scale for acute asthma in children. J Clin Epidemiol. 1992;45(1):71–6. 10.1016/0895-4356(92)90190-X

24. Smith SR, Baty JD, Hodge D3rd,. Validation of the pulmonary score: An asthma severity score for children. Acad Emerg Med. 2002;9(2):99–104. 10.1197/aemj.9.2.99

25. Abecassis L, Gaffin JM, Forbes PW, Schenkel SR, McBride S, DeGrazia M. Validation of the Hospital Asthma Severity Score (HASS) in children ages 2–18 years old. J Asthma. 2020:1–12. 10.1080/02770903.2020.1852414

26. Rodrigo GJ, Castro-Rodriguez JA. Anticholinergics in the treatment of children and adults with acute asthma: A systematic review with meta-analysis. Thorax. 2005;60(9):740–6. 10.1136/thx.2005.047803

27. Hasegawa K, Chiba T, Hagiwara Y, Watase H, Tsugawa Y, Brown DF, et al. Quality of care for acute asthma in emergency departments in Japan: A multicenter observational study. J Allergy Clin Immunol Pract. 2013;1(5):509–15.e1–3. 10.1016/j.jaip.2013.05.001

28. Adeyinka A, Bailey K, Pierre L, Kondamudi N. COVID 19 infection: Pediatric perspectives. J Am Coll Emerg Physicians Open. 2021;2(1):e12375. 10.1002/emp2.12375

29. Ash SY, Diaz AA. The role of imaging in the assessment of severe asthma. Curr Opin Pulm Med. 2017;23(1):97–102. 10.1097/MCP.0000000000000341

30. Narayanan S, Magruder T, Walley SC, Powers T, Wall TC. Relevance of chest radiography in pediatric inpatients with asthma. J Asthma. 2014;51(7):751–5. 10.3109/02770903.2014.909459

31. Majerus CR, Tredway TL, Yun NK, Gerard JM. Utility of chest radiographs in children presenting to a pediatric emergency department with acute asthma exacerbation and chest pain. Pediatr Emerg Care. 2021;37(7):e372–5. 10.1097/PEC.0000000000001615

32. Choi YJ, Park JY, Lee HS, Suh J, Song JY, Byun MK, et al. Effect of asthma and asthma medication on the prognosis of patients with COVID-19. Eur Respir J. 2021;57(3):2002226. 10.1183/13993003.02226-2020