Original Title: Exactitud diagnóstica de la oscilometría de impulso (IOS) comparada con la prueba de espirometría

Authors' objectives: To evaluate the diagnostic accuracy of IOS and the clinical utility in patients with chronic respiratory disease, small airway disease and/or cystic fibrosis who are unable to undergo spirometry or have uncertain spirometry results.

Authors' results and conclusions: The search yielded a total of 1958 references. From the title and abstract reading, 308 studies were selected for full text reading. Of these, only four studies that provided information on the diagnostic accuracy of IOS compared to spirometry met inclusion criteria. These studies were published between 2018 and 2023 and conducted in China, Egypt, India, and Iran. All were conducted in population older than 18 years of age, of both sexes. The studies assessed the validity of IOS for the detection and diagnosis of different clinical pictures related to COPD, asthma and bronchial asthma (small airway involvement, hyperactivity, etc.). No studies assessing cystic fibrosis were identified. The number and type of parameters used for diagnostic purposes was highly variable across studies. Regarding IOS, the most commonly used parameters to measure impedance were R5, R20 and their difference (R5-R20). The estimated sensitivity in the two studies that assessed the detection of small airway disease in patients with COPD was 56.9% and 83.3%, with a specificity of 76.2% and 100%, respectively. In the study that assessed the ability to detect small airway disease in asthma, the sensitivity was 100% and specificity 83.3%; in bronchial asthma, another study reported a sensitivity of 100% and specificity of 90.9%. Finally, the study that assessed the validity of IOS for the detection of airway hyperresponsiveness in patients with bronchial asthma found a sensitivity of 87.3% and a specificity of 64.6%. Overall, the positive predictive value (PPV) ranged from a minimum value of 64.6% to 100%. The quality of evidence was very low in all studies. No studies were identified that met the inclusion criteria and assessed the clinical usefulness of IOS versus spirometry in the pediatric population or in patients who were unable to undergo spirometry or had uncertain spirometry test results. A study was located that compared acceptability and satisfaction, and this study showed greater satisfaction with the IOS test than with spirometry in a population group >50 years of age. It is estimated that the IOS technique is a simple test that can be performed by nursing and/ or medical staff after explaining the performance instructions to the patient. It does not require additional training for the professionals interpreting the test. Nor would it imply modifications in the organization and delivery of the service. It has not been possible to locate any information on the costs of the technique.

Authors' methods: A bibliographic search of the scientific literature was carried out in the main biomedical databases in October 2023 and updated monthly until February 2024. The following databases were consulted: IHTA database, Cochrane Library, epistemonikos, tripdatabase, RedETS, Guia salud, G-I-N, TripDatabase, Medline, Embase, ISI Web of Science, clinicaltrials.gov, ICTRP (WHO). No time limit by date or language was applied. The following inclusion criteria were used: studies of diagnostic tests and randomized clinical trials, systematic reviews with or without meta-analysis, and observational studies that evaluated the usefulness of IOS compared to spirometry in children under 6 years of age and adults diagnosed with COPD, asthma, small airway disease, and cystic fibrosis who are unable to correctly perform spirometry testing due to inability to perform forced expiration. Only studies conducted in the last 10 years (2013 inclusive) published in English or Spanish were included. Letters to the editor, opinion articles, editorials and communications to congresses were excluded. The process of screening and selection of the studies was carried out with the Covidence tool. Screening by title and abstract was performed by two researchers and then full-text reading was performed by three researchers, both independently and blinded. Discrepancies were resolved by a fourth researcher. For data extraction, an ad hoc table was prepared in Excel. Data were extracted by two independent researchers. The quality of the evidence was assessed using the specific scales for each type of study, based on the recommendations of the “Guide for the preparation and adaptation of rapid health technology assessment reports” developed within the RedETS methodological line of work.

Project Status: Completed

Year Published: 2024

URL for published report: https://redets.sanidad.gob.es/productos/buscarProductos.do?metodo=detalle&id=1249

Requestor: Ministry of Health

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: Spain

Organisation Name: Scientific Advice Unit, avalia-t; The Galician Health Knowledge Agency (ACIS)

Contact Address: Conselleria de Sanidade, Xunta de Galicia, San Lazaro s/n 15781 Santiago de Compostela, Spain. Tel: 34 981 541831; Fax: 34 981 542854;

Contact Name: avalia-t@sergas.es

Contact Email: avalia-t@sergas.es

Copyright: <p>Galician Agency for Health Technology Assessment (AVALIA-T)</p>