Publications
Multiple researchers and PhD students have contributed to the publications produced so far from the BILD study. Here we list some of the most relevant articles that have come out of the research we have carried out over the years. If you are interested in learning more details about the BILD study design, methodology, and strategic aims, a good place to start would be the cohort profile publication, accessed free-of-charge via the following link: https://ije.oxfordjournals.org/content/41/2/366.full.pdf+html
Oliver Fuchs, Philipp Latzin, Claudia E Kuehni, Urs Frey (2012) Cohort profile: the Bern infant lung development cohort. International journal of epidemiology 41: 2. 366-376 Apr.
2023
Antibiotics in pregnancy influence nasal microbiome and respiratory morbidity in infancy. Rüttimann C, Nissen-Kratzert A, Mostacci N, Künstle N, Marten A, Gisler A, Bacher K, Yammine S, Steinberg R, Schulzke S, Röösli M, Latzin P, Hilty M, Frey U, Gorlanova O. ERJ Open Res. 2023 Aug 29;9(4):00225-2023. doi: 10.1183/23120541.00225-2023. PMID: 37650088; PMCID: PMC10463034.
Ambient prenatal air pollution exposure is associated with low cord blood IL-17a in infants. Gorlanova O, Oller H, Marten A, Müller L, Laine-Carmelli J, Decrue F, Salem Y, Vienneau D, Hoogh K, Gisler A, Usemann J, Korten I, Yammine S, Nahum U, Künstle N, Sinues P, Schulzke S, Latzin P, Fuchs O, Röösli M, Schaub B, Frey U; BILD study group. Pediatr Allergy Immunol. 2023 Jan;34(1):e13902. doi: 10.1111/pai.13902. PMID: 36705042
2022
Pollen exposure is associated with risk of respiratory symptoms during the first year of life. Gisler A, Eeftens M, de Hoogh K, Vienneau D, Salem Y, Yammine S, Jakob J, Gorlanova O, Decrue F, Gehrig R, Frey U, Latzin P, Fuchs O, Usemann J; BILD study group.Allergy. 2022 Dec;77(12):3606-3616. doi: 10.1111/all.15284. Epub 2022 Mar 28.PMID: 35302662
2021
Increased Impact of Air Pollution on Lung Function in Preterm vs. Term Infants: The BILD Study. Decrue F, Gorlanova O, Salem Y, Vienneau D, de Hoogh K, Gisler A, Usemann J, Korten I, Nahum U, Sinues P, Schulzke S, Fuchs O, Latzin P, Röösli M, Frey U; BILD7 study group. Am J Respir Crit Care Med. 2021 Sep 29. doi: 10.1164/rccm.202102-0272OC. Online ahead of print. PMID: 34587471
Can biomarkers in umbilical cord blood predict atopic disease at school age? Soti AL, Usemann J, Schaub B, Frey U, Latzin P, Fuchs O; BILD Study group.Pediatr Res. 2021 Jan;89(2):389-392. doi: 10.1038/s41390-019-0686-z. Epub 2019 Dec 6. PMID: 31810077 No abstract available.
Shedding light into the black box of infant multiple-breath washout. Oestreich MA, Wyler F, Latzin P, Ramsey KAPediatr Pulmonol. 2021 Aug;56(8):2642-2653. doi: 10.1002/ppul.25464. Epub 2021 May 25. PMID: 33991038
Are children born by cesarean section at higher risk for respiratory sequelae? Salem Y, Oestreich MA, Fuchs O, Usemann J, Frey U, Surbek D, Amylidi-Mohr S, Latzin P, Ramsey K, Yammine S; BILD study group. Am J Obstet Gynecol. 2021 Aug 5:S0002-9378(21)00866-8. doi: 10.1016/j.ajog.2021.07.027. Online ahead of print. PMID: 34364843
Respiratory symptoms do not reflect functional impairment in early CF lung disease. Korten I, Oestreich MA, Frey U, Moeller A, Jung A, Spinas R, Mueller-Suter D, Trachsel D, Rochat I, Spycher B, Latzin P, Casaulta C, Ramsey K; SCILD, and BILD, study group.J Cyst Fibros. 2021 Jun 1:S1569-1993(21)00116-8. doi: 10.1016/j.jcf.2021.04.006. Online ahead of print. PMID: 34088612
Associations of air pollution and greenness with the nasal microbiota of healthy infants: A longitudinal study. Gisler A, Korten I, de Hoogh K, Vienneau D, Frey U, Decrue F, Gorlanova O, Soti A, Hilty M, Latzin P, Usemann J; BILD study group. Environ Res. 2021 Jul 10;202:111633. doi: 10.1016/j.envres.2021.111633. Online ahead of print. PMID: 34256075
Maternal asthma is associated with reduced lung function in male infants in a combined analysis of the BLT and BILD cohorts. de Gouveia Belinelo P, Collison AM, Murphy VE, Robinson PD, Jesson K, Hardaker K, de Queiroz Andrade E, Oldmeadow C, Martins Costa Gomes G, Sly PD, Usemann J, Appenzeller R, Gorlanova O, Fuchs O, Latzin P, Gibson PG, Frey U, Mattes J. Thorax. 2021 Feb 25:thoraxjnl-2020-215526. doi: 10.1136/thoraxjnl-2020-215526. Online ahead of print. PMID: 33632766
Correction of sensor crosstalk error in Exhalyzer D multiple-breath washout device significantly impacts outcomes in children with cystic fibrosis. Wyler F, Oestreich MA, Frauchiger BS, Ramsey KA, Latzin PT. J Appl Physiol (1985). 2021 Aug 5. doi: 10.1152/japplphysiol.00338.2021. Online ahead of print. PMID: 34351818
2020
Normative data for multiple breath washout outcomes in school-aged Caucasian children. Anagnostopoulou P, Latzin P, Jensen R, Stahl M, Harper A, Yammine S, Usemann J, Foong RE, Spycher B, Hall GL, Singer F, Stanojevic S, Mall MA, Ratjen F, Ramsey KA. Eur Respir J. 2020 Apr 3;55(4):1901302. doi: 10.1183/13993003.01302-2019. Print 2020 Apr. PMID: 31862765
Effect of breastfeeding duration on lung function, respiratory symptoms and allergic diseases in school-age children. Gorlanova O, Appenzeller R, Mahmoud YS, Ramsey KA, Usemann J, Decrue F, Kuehni CE, Röösli M, Latzin P, Fuchs O, Soti A, Frey U; BILD Study Group.Pediatr Pulmonol. 2020 Mar 17. doi: 10.1002/ppul.24733. [Epub ahead of print] PMID: 32181595
2019
Exposure to moderate air pollution and associations with lung function at school-age: A birth cohort study. Usemann J, Decrue F, Korten I, Proietti E, Gorlanova O, Vienneau D, Fuchs O, Latzin P, Röösli M, Frey U; BILD study group. Environ Int. 2019 May;126:682-689. doi: 10.1016/j.envint.2018.12.019. Epub 2019 Mar 11. PMID: 30870661
Can biomarkers in umbilical cord blood predict atopic disease at school age? Soti AL, Usemann J, Schaub B, Frey U, Latzin P, Fuchs O; BILD Study group. Pediatr Res. 2019 Dec 6. doi: 10.1038/s41390-019-0686-z. [Epub ahead of print] No abstract available. PMID: 31810077
Variability of Tidal Breathing Parameters in Preterm Infants and Associations with Respiratory Morbidity during Infancy: A Cohort Study. Usemann J, Suter A, Zannin E, Proietti E, Fouzas S, Schulzke S, Latzin P, Frey U; BILD study group. J Pediatr. 2019 Feb;205:61-69.e1. doi: 10.1016/j.jpeds.2018.10.002. Epub 2018 Nov 8. PMID: 30416016
Respiratory rate in infants with cystic fibrosis throughout the first year of life and association with lung clearance index measured shortly after birth. Korten I, Kieninger E, Yammine S, Cangiano G, Nyilas S, Anagnostopoulou P, Singer F, Kuehni CE, Regamey N, Frey U, Casaulta C, Spycher BD, Latzin P; SCILD; BILD study group. J Cyst Fibros. 2019 Jan;18(1):118-126. doi: 10.1016/j.jcf.2018.07.002. Epub 2018 Jul 27. PMID: 30060960
Nasal Microbiota and Respiratory Tract Infections: The Role of Viral Detection. Korten I, Ramsey K, Mika M, Usemann J, Frey U, Hilty M, Latzin P. Am J Respir Crit Care Med. 2019 Apr 1;199(7):919-922. doi: 10.1164/rccm.201710-2020LE. No abstract available. PMID: 29518345
Addressing the complexity of prenatal and postnatal environmental exposures affecting childhood lung function. Frey U, Usemann J. Volume 3, ISSUE 2, Pe51-e52. Lancet Planetary Health (2019) DOI:https://doi.org/10.1016/S2542-5196(19)30011-7
2018
Dynamics of respiratory symptoms during infancy and associations with wheezing at school age. Usemann J, Xu B, Delgado-Eckert E, Korten I, Anagnostopoulou P, Gorlanova O, Kuehni C, Röösli M, Latzin P, Frey U. ERJ Open Res. 2018 Nov 20;4(4). pii: 00037-2018. doi: 10.1183/23120541.00037-2018. eCollection 2018 Oct. PMID:30474038
Variability of Tidal Breathing Parameters in Preterm Infants and Associations with Respiratory Morbidity during Infancy: A Cohort Study. Usemann J, Suter A, Zannin E, Proietti E, Fouzas S, Schulzke S, Latzin P, Frey U; BILD study group. J Pediatr. 2018 Nov 8. pii: S0022-3476(18)31414-8. doi: 10.1016/j.jpeds.2018.10.002. [Epub ahead of print] PMID:30416016
Neighbourhood child population density as a proxy measure for exposure to respiratory infections in the first year of life: A validation study. Lupatsch JE, Kreis C, Korten I, Latzin P, Frey U, Kuehni CE, Spycher BD. PLoS One. 2018 Sep 12;13(9):e0203743. doi: 10.1371/journal.pone.0203743. eCollection 2018. PMID: 30208077
Protective effects of breastfeeding on respiratory symptoms in infants with 17q21 asthma risk variants. Gorlanova O, Illi S, Toncheva AA, Usemann J, Latzin P, Kabesch M, Dalphin JC, Lauener R, Pekkanen JR, Von Mutius E, Riedler J, Kuehni CE, Röösli M, Frey U; BILD and PASTURE study groups. Allergy. 2018 Dec;73(12):2388-2392. doi: 10.1111/all.13568. Epub 2018 Aug 9. No abstract available. PMID: 30030842
Response of cord blood cells to environmental, hereditary and perinatal factors: A prospective birth cohort study. Lurà MP, Gorlanova O, Müller L, Proietti E, Vienneau D, Reppucci D, Pavlovic R, Dahinden C, Röösli M, Latzin P, Frey U. PLoS One. 2018 Jul 6;13(7):e0200236. doi: 10.1371/journal.pone.0200236. eCollection 2018. PMID: 29979752
Glucocorticoid metabolites in newborns: A marker for traffic noise related stress? Cantuaria ML, Usemann J, Proietti E, Blanes-Vidal V, Dick B, Flück CE, Rüedi S, Héritier H, Wunderli JM, Latzin P, Frey U, Röösli M, Vienneau D; BILD study group. Environ Int. 2018 Aug;117:319-326. doi: 10.1016/j.envint.2018.05.002. Epub 2018 May 17. PMID: 29778832
Nasal Microbiota and Respiratory Tract Infections: The Role of Viral Detection. Korten I, Ramsey K, Mika M, Usemann J, Frey U, Hilty M, Latzin P. Am J Respir Crit Care Med. 2018 Mar 8. doi: 10.1164/rccm.201710-2020LE. [Epub ahead of print] No abstract available. PMID: 29518345
Respiratory viruses in healthy infants and infants with cystic fibrosis: a prospective cohort study. Korten I, Kieninger E, Klenja S, Mack I, Schläpfer N, Barbani MT, Regamey N, Kuehni CE, Hilty M, Frey U, Gorgievski M, Casaulta C, Latzin P; SCILD and BILD study groups. Thorax. 2018 Jan;73(1):13-20. doi: 10.1136/thoraxjnl-2016-209553. Epub 2017 Aug 4. DOI: 10.1136/thoraxjnl-2016-209553. PMID: 28778921
Infant multiple breath washout using a new commercially available device: Ready to replace the previous setup? Kentgens AC, Guidi M, Korten I, Kohler L, Binggeli S, Singer F, Latzin P, Anagnostopoulou P. Pediatr Pulmonol. 2018 May;53(5):628-635. doi: 10.1002/ppul.23959. Epub 2018 Feb 8. PMID: 29418075
Lower exhaled nitric oxide in infants with Cystic Fibrosis compared to healthy controls. Korten I, Liechti M, Singer F, Hafen G, Rochat I, Anagnostopoulou P, Müller-Suter D, Usemann J, Moeller A, Frey U, Latzin P, Casaulta C; SCILD and BILD study group. J Cyst Fibros. 2018 Jan;17(1):105-108. doi: 10.1016/j.jcf.2017.05.005. Epub 2017 Jul 14. PMID: 28716479
2017
Kieninger E, Yammine S, Korten I, Anagnostopoulou P, Singer F, Frey U, Mornand A, Zanolari M, Rochat I, Trachsel D, Mueller-Suter D, Moeller A, Casaulta C, Latzin P; and the SCILD; and BILD study groups. Elevated lung clearance index in infants with cystic fibrosis shortly after birth. Eur Respir J. 2017 Nov 9;50(5). PMID: 29122915
Korten I, Kieninger E, Klenja S, Mack I, Schläpfer N, Barbani MT, Regamey N, Kuehni CE, Hilty M, Frey U, Gorgievski M, Casaulta C, Latzin P; SCILD and BILD study groups. Respiratory viruses in healthy infants and infants with cystic fibrosis: a prospective cohort study. Thorax. 2017 Aug 4. PMID: 28778921 [epub]
Fuchs O, Gorlanova O, Latzin P, Schmidt A, Schieck M, Toncheva AA, Michel S, Gaertner VD, Kabesch M, Frey U. 6q12 and 11p14 variants are associated with postnatal exhaled nitric oxide levels and respiratory symptoms. J Allergy Clin Immunol. 2017 Oct;140(4):1015-1023. PMID: 28109725
Kentgens AC, Anagnostopoulou P, Singer F, Latzin P. Unexpected results in infant multiple breath washout: Is the truth hidden in the washin? Pediatr Pulmonol. 2017 Jun;52(6):717-719. PMID: 28474490
Jost K, Egger B, Kieninger E, Singer F, Frey U, Latzin P. Changes in minute ventilation after exposure to 4% sulfur hexafluoride (SF6 ) in infants. Pediatr Pulmonol. 2017 Feb;52(2):151-153. PMID: 27589241
Korten I, Ramsey K, Latzin P. Air pollution during pregnancy and lung development in the child. Paediatr Respir Rev. 2017 Jan;21:38-46. PMID: 27665510
Usemann J, Demann D, Anagnostopoulou P, Korten I, Gorlanova O, Schulzke S, Frey U, Latzin P. Interrupter technique in infancy: Higher airway resistance and lower short-term variability in preterm versus term infants. Pediatr Pulmonol. 2017 Oct; 52 (10):1355-1362. PMID: 28771980
Korten, I, Liechti M, Singer F, Hafen G, Rochat I, Anagnostopoulou P, Mueller-Suter D, Usemann J, Moeller A, Frey U, Latzin P, Casaulta C; SCILD and BILD study groups. Lower exhaled nitric oxide in infants with Cystic Fibrosis compared to healthy controls. J Cyst Fibros. 2017 Jul. 14. PMID: 28716479
2016
Korten I, Mika M, Klenja S, Kieninger E, Mack I, Barbani MT, Gorgievski M, Frey U, Hilty M, Latzin P. Interactions of Respiratory Viruses and the Nasal Microbiota during the First Year of Life in Healthy Infants. mSphere. 2016 Nov 23;1(6). PMID: 27904883
Yammine S, Summermatter S, Singer F, Lauener R, Latzin P. Feasibility of nitrogen multiple-breath washout in inexperienced children younger than 7 years. Pediatr Pulmonol. 2016 Nov;51(11):1183-1190. PMID: 27132707
Jost K, Egger B, Kieninger E, Singer F, Frey U, Latzin P. Changes in minute ventilation after exposure to 4% sulfur hexafluoride (SF6 ) in infants. Pediatr Pulmonol. 2016 Sep 2. PMID: 27589241
Usemann J, Fuchs O, Anagnostopoulou P, Korten I, Gorlanova O, Röösli M, Latzin P, Frey U. Predictive value of exhaled nitric oxide in healthy infants for asthma at school age. Eur Respir J. 2016 Sep;48(3):925-8. PMID: 27390276
Mack I, Kieninger E, Cangiano G, Tapparel C, Kuehni C, Spycher B, Kaiser L, Frey U, Regamey N, Latzin P. Rhinovirus Infections and Associated Respiratory Morbidity in Infants: A Prospective Cohort Study. Pediatr Infect Dis J. 2016 Oct;35(10):1069-74. PMID: 27254029
Egger B, Jost K, Anagnostopoulou P, Yammine S, Singer F, Casaulta C, Frey U, Latzin P. Lung clearance index and moment ratios at different cut-off values in infant multiple-breath washout measurements. Pediatr Pulmonol. 2016 Dec;51(12):1373-1381. PMID: 27214661
Usemann J, Frey U, Mack I, Schmidt A, Gorlanova O, Röösli M, Hartl D, Latzin P. CHI3L1 polymorphisms, cord blood YKL-40 levels and later asthma development. BMC Pulm Med. 2016 May 18;16(1):81. PMID: 27193312
Mika M, Korten I, Qi W, Regamey N, Frey U, Casaulta C, Latzin P, Hilty M; SCILD study group. The nasal microbiota in infants with cystic fibrosis in the first year of life: a prospective cohort study. Lancet Respir Med. 2016 Aug;4(8):627-35. PMID: 27180018
Gorlanova O, Thalmann S, Proietti E, Stern G, Latzin P, Kühni C, Röösli M, Frey U. Effects of Breastfeeding on Respiratory Symptoms in Infancy. J Pediatr. 2016 Jul;174:111-117.e5. PMID: 27063808
Jost K, Lenherr N, Singer F, Schulzke SM, Frey U, Latzin P, Yammine S. Changes in breathing pattern upon 100% oxygen in children at early school age. Respir Physiol Neurobiol. 2016 Jul;228:9-15. PMID: 26970571
Anagnostopoulou P, Egger B, Lurà M, Usemann J, Schmidt A, Gorlanova O, Korten I, Roos M, Frey U, Latzin P. Multiple breath washout analysis in infants: quality assessment and recommendations for improvement. Physiol Meas. 2016 Mar;37(3):L1-L15. PMID: 26849570
Yammine S, Schmidt A, Sutter O, Fouzas S, Singer F, Frey U, Latzin P. Functional evidence for continued alveolarisation in former preterms at school age? Eur Respir J. 2016 Jan;47(1):147-55. PMID: 26493788
2015
Urs Frey, Philipp Latzin, Jakob Usemann, Janet Maccora, Urs Zumsteg, S Kriemler (2015) Asthma and obesity in children: current evidence and potential systems biology approaches. Allergy 70: 1. 26-40 Jan.
Moana Mika, Ines Mack, Insa Korten, Weihong Qi, Suzanne Aebi, Urs Frey, Philipp Latzin, Markus Hilty (2015) Dynamics of the nasal microbiota in infancy: a prospective cohort study. The Journal of allergy and clinical immunology 135: 4. 905-12.e11 Apr.
Loretta Müller, Ines Mack, Caroline Tapparel, Laurent Kaiser, Marco P Alves, Elisabeth Kieninger, Urs Frey, Nicolas Regamey, Philipp Latzin (2015) Human Rhinovirus Types and Association with Respiratory Symptoms During the First Year of Life. The Pediatric infectious disease journal May.
2014
Anne Schmidt, Sophie Yammine, Elena Proietti, Urs Frey, Philipp Latzin, Thomas Riedel, Florian Singer (2014) Validation of multiple-breath washout equipment for infants and young children. Pediatric pulmonology Feb.
Sotirios Fouzas, Christoph Häcki, Philipp Latzin, Elena Proietti, Sven Schulzke, Urs Frey, Edgar Delgado-Eckert (2014) Volumetric capnography in infants with bronchopulmonary dysplasia. The Journal of pediatrics 164: 2. 283-8.e1-3 Feb.
Elena Proietti, Thomas Riedel, Oliver Fuchs, Isabelle Pramana, Florian Singer, Anne Schmidt, Claudia Kuehni, Philipp Latzin, Urs Frey (2014) Can infant lung function predict respiratory morbidity during the first year of life in preterm infants? The European respiratory journal 43: 6. 1642-1651 Jun.
Florian Singer, Chiara Abbas, Sophie Yammine, Carmen Casaulta, Urs Frey, Philipp Latzin (2014) Abnormal small airways function in children with mild asthma. Chest 145: 3. 492-499 Mar.
Florian Singer, Sophie Yammine, Anne Schmidt, Elena Proietti, Elisabeth Kieninger, Juerg Barben, Carmen Casaulta, Nicolas Regamey, Per Gustafsson, Urs Frey, Philipp Latzin (2014) Ventilatory response to nitrogen multiple-breath washout in infants. Pediatric pulmonology 49: 4. 342-347 Apr.
2013
Elisabeth Kieninger, Oliver Fuchs, Philipp Latzin, Urs Frey, Nicolas Regamey (2013) Rhinovirus infections in infancy and early childhood. The European respiratory journal 41: 2. 443-452 Feb.
Elena Proietti, Martin Röösli, Urs Frey, Philipp Latzin (2013) Air pollution during pregnancy and neonatal outcome: a review. Journal of aerosol medicine and pulmonary drug delivery 26: 1. 9-23 Feb.
Florian Singer, et al. A new double-tracer gas single-breath washout to assess early cystic fibrosis lung disease. Eur Respir J 41, 339-345 (2013).
Florian Singer, Elisabeth Kieninger, Chiara Abbas, Sophie Yammine, Oliver Fuchs, Elena Proietti, Nicolas Regamey, Carmen Casaulta, Urs Frey, Philipp Latzin (2013) Practicability of nitrogen multiple-breath washout measurements in a pediatric cystic fibrosis outpatient setting. Pediatric pulmonology 48: 8. 739-746 Aug
Sven M Schulzke, Urs Frey (2013) Consensus statement on inert gas washout measurement: at the threshold of clinical use. The European respiratory journal 41: 3. 500-502 Mar.
Vienneau, D. et al. Western European land use regression incorporating satellite- and ground-based measurements of NO2 and PM10. Environmental science & technology 47, 13555-13564 (2013).
2002-2012
Oliver Fuchs, Philipp Latzin, Claudia E Kuehni, Urs Frey (2012) Cohort profile: the Bern infant lung development cohort. International journal of epidemiology 41: 2. 366-376 Apr.
Oliver Fuchs, Philipp Latzin, Florian Singer, Nicole Petrus, Elena Proietti, Elisabeth Kieninger, Carmen Casaulta, Urs Frey (2012) Comparison of online single-breath vs. online multiple-breath exhaled nitric oxide in school-age children. Pediatric research 71: 5. 605-611 May.
Latzin, P. et al. Exposure to moderate air pollution during late pregnancy and cord blood cytokine secretion in healthy neonates. PLoS One 6, e23130 (2011).
Fuchs, O. et al. Normative data for lung function and exhaled nitric oxide in unsedated healthy infants. Eur Respir J 37, 1208-1216 (2011).
Frey, U. & von Mutius, E. The challenge of managing wheezing in infants. N Engl J Med 360, 2130-2133 (2009).
Latzin, P., Roosli, M., Huss, A., Kuehni, C. E. & Frey, U. Air pollution during pregnancy and lung function in newborns: a birth cohort study. Eur Respir J 33, 594-603 (2009).
Frey, U. & Suki, B. Complexity of chronic asthma and chronic obstructive pulmonary disease: implications for risk assessment, and disease progression and control. Lancet 372, 1088-1099 (2008).
von Mutius, E. & Le Souef, P. N. Early gene-environment interactions: can they inform primary preventive strategies for asthma? Semin Respir Crit Care Med 28, 255-263 (2007).
Latzin, P. et al. Prospectively assessed incidence, severity, and determinants of respiratory symptoms in the first year of life. Pediatr Pulmonol 42, 41-50 (2007).
Latzin, P. et al. Optimized temperature and deadspace correction improve analysis of multiple breath washout measurements by ultrasonic flowmeter in infants. Pediatr Pulmonol 42, 888-897 (2007).
Latzin, P. et al. Elevated exhaled nitric oxide in newborns of atopic mothers precedes respiratory symptoms. Am J Respir Crit Care Med 174, 1292-1298 (2006).
Kuehni, C. E. & Frey, U. Age-related differences in perceived asthma control in childhood: guidelines and reality. Eur Respir J 20, 880-889 (2002).