{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T05:57:57Z","timestamp":1791266277815,"version":"4.1.0"},"reference-count":18,"publisher":"National Institute for Health and Care Research","license":[{"start":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T00:00:00Z","timestamp":1785456000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001921","name":"Public Health Research Programme","doi-asserted-by":"publisher","award":["NIHR129783"],"award-info":[{"award-number":["NIHR129783"]}],"id":[{"id":"10.13039\/501100001921","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["openresearch.nihr.ac.uk"],"crossmark-restriction":false},"short-container-title":["NIHR Open Res"],"abstract":"<ns5:p>Background Respiratory infections are a leading cause of mortality and morbidity among older adults in residential care homes. We conducted a qualitative study within the \u2018Air Filtration to prevent symptomatic winter Respiratory Infections (including COVID-19) in care homes (AFRI-c)\u2019 pragmatic cluster randomised controlled trial. This paper reports the lessons learned from using high-efficiency particulate air (HEPA) filtration units in a care home setting. Methods Interviews with care home staff (n=25), residents (n=20), and relatives (n=12) who participated in the AFRI-c trial were analysed using reflexive thematic analysis. Results Preventing respiratory infections was a high priority for staff. Although using HEPA filters became normalised during the intervention period, they were not considered suitable for all residents. The ability to lock settings or fix them to walls was identified as a potential way to improve them in this setting. Participants felt that the care home sector would be unable to afford the cost of HEPA filters for all residents and that their use would be prioritised for those with the greatest need. However, without financial support, HEPA filters may only be used by residents who can afford them. Staff felt that HEPA filters might be attractive to potential residents and their families, but consultees and residents were both more focused on overall quality of care and life. Maintenance of the HEPA filters had a minor impact on staff workload. Conclusions Although the AFRI-c trial found that HEPA filters did not reduce respiratory infections in residents, these insights could be valuable for care homes wishing to use HEPA filters for other reasons, such as reducing airborne pollutants and allergens. With some adaptions, portable HEPA filters could be made more suitable for use in care home settings. There were concerns that without financial support, inequalities could deepen.<\/ns5:p>","DOI":"10.3310\/nihropenres.13993.1","type":"journal-article","created":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T14:25:15Z","timestamp":1790864715000},"page":"111","update-policy":"https:\/\/doi.org\/10.3310\/nihropenres.crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Lessons learned from using high efficiency particulate air (HEPA) filtration units in care homes: interviews with care home staff, residents and relatives from the AFRI-c trial"],"prefix":"10.3310","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4399-2049","authenticated-orcid":false,"given":"Sophie","family":"Rees","sequence":"first","affiliation":[{"name":"Bristol Trials Centre Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel","family":"Brierley","sequence":"additional","affiliation":[{"name":"Bristol Trials Centre Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clare","family":"Clement","sequence":"additional","affiliation":[{"name":"Centre for Appearance Research Bristol England University of the West of England"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alastair","family":"Hay","sequence":"additional","affiliation":[{"name":"Centre for Academic Primary Care Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Sargent","sequence":"additional","affiliation":[{"name":"Bristol Trials Centre Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jane","family":"Sprackman","sequence":"additional","affiliation":[{"name":"Bristol Trials Centre Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruth","family":"Kipping","sequence":"additional","affiliation":[{"name":"Centre for Public Health Bristol England University of Bristol Medical School"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"6221","published-online":{"date-parts":[[2026,7,31]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1186\/s12877-015-0073-5","article-title":"Antibiotic use in the care home setting: a retrospective cohort study analysing routine data.","volume":"15","author":"P Sundvall","year":"2015","journal-title":"BMC Geriatr."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"685-696","DOI":"10.1093\/oxfordjournals.aje.a116348","article-title":"Intensive surveillance for infections in a three-year study of nursing home patients.","volume":"135","author":"M Jackson","year":"1992","journal-title":"Am J Epidemiol."},{"key":"ref3","article-title":"Indoor airborne risk assessment in the context of SARS-CoV-2: description of airborne transmission mechanism and method to develop a new standardized model for risk assessment","year":"2024"},{"key":"ref4","article-title":"Philips AC4600 H1N1 air purification certificate","author":"B Mitchell","year":"2014"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0251049","article-title":"Should homes and workplaces purchase portable air filters to reduce the transmission of SARS-CoV-2 and other respiratory infections? A systematic review.","volume":"16","author":"A Hammond","year":"2021","journal-title":"PLoS One."},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.1016\/j.ypmed.2023.107774","article-title":"Effectiveness of filtering or decontaminating air to reduce or prevent respiratory infections: a systematic review.","volume":"177","author":"J Brainard","year":"2023","journal-title":"Prev Med."},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1001\/jamainternmed.2026.2199","article-title":"High-Efficiency Particulate Air Filters to Prevent Winter Respiratory Infections in Care Homes: The AFRI-c Cluster Randomized Clinical Trial.","author":"A Hay","year":"2026","journal-title":"JAMA Intern Med."},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0347989","article-title":"Implementation and acceptability of high efficiency particulate air filters to reduce respiratory infections in care homes: Process evaluation of the AFRI-c cluster randomised controlled 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double-blind, placebo-controlled trial.","volume":"130","author":"W Fong","year":"2023","journal-title":"Ann Allergy Asthma Immunol."},{"key":"ref12","article-title":"Thematic analysis: a practical guide","author":"V Braun","year":"2021"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"77-101","DOI":"10.1191\/1478088706qp063oa","article-title":"Using thematic analysis in psychology.","volume":"3","author":"V Braun","year":"2006","journal-title":"Qual Res Psychol."},{"key":"ref14","article-title":"WMA declaration of Helsinki \u2013 ethical principles for medical research involving human subjects","year":"2024"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"e29","DOI":"10.2196\/mhealth.5127","article-title":"Designing, implementing, and evaluating mobile health technologies for managing chronic conditions in older adults: a scoping review.","volume":"4","author":"N Matthew-Maich","year":"2016","journal-title":"JMIR Mhealth Uhealth."},{"key":"ref16","article-title":"High efficiency particulate air filtration to prevent symptomatic winter respiratory infections (including COVID-19) in care homes: the AFRI-c cluster randomised controlled trial","author":"A Hay"},{"key":"ref17","doi-asserted-by":"publisher","DOI":"10.5523\/bris.250w5vo8i6he32dc6y3plrq8d9","article-title":"High efficiency particulate air filters to prevent symptomatic winter respiratory infections including COVID-19 in care homes: the AFRI-c pragmatic cluster randomised trial","author":"A Hay","year":"2025"},{"key":"ref18","doi-asserted-by":"publisher","DOI":"10.5523\/bris.106jsm1tvvsg62gf2d1tofsh57","article-title":"AFRI-c qualitative study materials","author":"S Rees","year":"2025"}],"updated-by":[{"DOI":"10.3310\/nihropenres.13993.2","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:00:00Z","timestamp":1791244800000}}],"container-title":["NIHR Open Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1\/iparadigms","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T05:29:10Z","timestamp":1791264550000},"score":1,"resource":{"primary":{"URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,31]]},"references-count":18,"URL":"https:\/\/doi.org\/10.3310\/nihropenres.13993.1","relation":{"has-review":[{"id-type":"doi","id":"10.3310\/nihropenres.15213.r41711","asserted-by":"subject"},{"id-type":"doi","id":"10.3310\/nihropenres.15213.r41961","asserted-by":"subject"},{"id-type":"doi","id":"10.3310\/nihropenres.15213.r41964","asserted-by":"subject"}],"is-version-of":[{"id-type":"doi","id":"10.3310\/nihropenres.13993.2","asserted-by":"object"}]},"ISSN":["2633-4402"],"issn-type":[{"value":"2633-4402","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,31]]},"assertion":[{"value":"Indexed","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#article-reports","order":0,"name":"referee-status","label":"Referee status","group":{"name":"current-referee-status","label":"Current Referee Status"}},{"value":"10.3310\/nihropenres.15213.r41711, Julii Brainard, University of East Anglia, Norwich, England, 28 Aug 2026, version 1, indexed","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#referee-response-41711","order":0,"name":"referee-response-41711","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Sophie Rees<\/b>; \n<i>Posted: 25 Sep 2026<\/i>; \n<b>Reviewer 1<\/b> This is useful and clearly written. I was impressed by the pragmatism of the respondents in figuring out what they thought about the filters. My comments amount to quite minor revisions. Some additional references are suggested (hence \u201cpartly\u201d on the grading for citation of up to date literature). With regard to data availability I graded this as partly because the data are supplied upon request (which is entirely reasonable and appropriate) rather than immediately available. I graded the submission as \u201cpartly\u201d for replicability because I was unable to access the supplemental data repository (\u201csite not found\u201d) https:\/\/doi.org\/10.5523\/bris.250w5vo8i6he32dc6y3plrq8d9&nbsp; (that link didn\u2019t work; perhaps because this item is still unpublished).  \n<b><i>Response: We have checked and confirmed that this link is now working.<\/i><\/b>  All of those things should be acceptable (data availability) or easily fixed before indexing (additional refs and access to documents like the topic guides). On the manuscript itself, I was struck by the lack of description about cost-effectiveness results.&nbsp; Cost-effectiveness was part of the original protocol.&nbsp; Presumably because of the lack of difference between groups in infection rates, no formal CE comparison was undertaken.&nbsp; But then the article does talk about capital and running cost of the HEPA units, and needing \u201cstrong\u201d evidence in favour of their use for them to be widely adopted on cost grounds, and thus unnecessary\/unprotective expenditure becomes very relevant.&nbsp;&nbsp; It seemed odd to not have at least a sentence saying something that the units as deployed in this experiment were inherently not cost-effective for infection prevention and quite possibly not even cost-effective to prevent asthma attacks or COPD exacerbation, see results in this syst. Review for instance:&nbsp; https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC13064970\/  \n<b><i>Response: While we appreciate the reviewer\u2019s point, our cost-effectiveness results are due to be published elsewhere, and our clinical results are already published. We have intentionally avoided replicating discussion of clinical- and cost-effectiveness results to keep this article focused on useful lessons learned for future research or other circumstances where air filters may be used in the residential care setting.<\/i><\/b>  There is a good-looking protocol for syst review about asthma prevention using air filters; I can\u2019t find a published version of the results but I would (email those review protocol authors to ask if they have published because I would) want to cite that review\u2019s results in this \u201dlessons learned\u201d Afri-c article.&nbsp; https:\/\/bmjopen.bmj.com\/content\/14\/12\/e087493.abstract  \n<b><i>Response: As above \u2013 an interesting article but discussion of clinical\/cost effectiveness is beyond the scope of this article.<\/i><\/b>  Methods: please explain what is \u201cMode one\u201d ?&nbsp; Low rate of air flow, maybe? \u2026 what are \u201cstudy champions\u201d?&nbsp; What role did they have in general?  \n<b><i>Response: We have added further description of these points.<\/i><\/b>  References (even just one Ref for each of next 2 points) could be added to further describe \u2026 \u2026what is maximum variation purposive sampling \u2026what is IMD, which is presumably 2019 version  \n<b><i>Response: References added.<\/i><\/b>  The sentence that ends \u201csomeone had gone through the information with residents before the visit, and that they understood we were visiting.\u201d Should that say \u201csomeone had gone through the information with residents before the visit, and that they understood why we were visiting.\u201d  \n<b><i>Response: Thank you, amended.<\/i><\/b>  RESULTS, I wondered if 57 participants were \u201cfrom\u201d care homes or \u201cassociated with\u201d the care homes  \n<b><i>Response: Amended as per this suggestion.<\/i><\/b>  OTHER COMMENTS The PPI was well explained and sounded well-incorporated; exemplary really.  \n<b><i>Response: We thank the reviewer for their kind comments on our article.<\/i><\/b>","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#referee-comment-3633","order":1,"name":"referee-comment-3633","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.3310\/nihropenres.15213.r41961, Alice Turner, University of Birmingham, Birmingham, England, 02 Sep 2026, version 1, indexed","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#referee-response-41961","order":2,"name":"referee-response-41961","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Sophie Rees<\/b>; \n<i>Posted: 25 Sep 2026<\/i>; Thank you to this reviewer for their report and kind words. We refer this reviewer to our clinical results paper and Supplement 2 which report multiple pre-planned subgroup and secondary outcome analyses:&nbsp; Hay AD, Brierley RCM, Turner N, et al. High-Efficiency Particulate Air Filters to Prevent Winter Respiratory Infections in Care Homes: The AFRI-c Cluster Randomized Clinical Trial. \n<i>JAMA Intern Med.<\/i> 2026;186(9):1124\u20131134. doi:10.1001\/jamainternmed.2026.2199","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#referee-comment-3634","order":3,"name":"referee-comment-3634","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.3310\/nihropenres.15213.r41964, Douglas Booker, University of Leeds, Leeds, 01 Oct 2026, version 1, indexed","URL":"https:\/\/openresearch.nihr.ac.uk\/articles\/6-111\/v1#referee-response-41964","order":4,"name":"referee-response-41964","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"This project is funded by the National Institute for Health Research (NIHR) under its Public Health Research (PHR) Programme NIHR129783. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.","order":5,"name":"grant-information","label":"Grant Information"},{"value":"This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.","order":0,"name":"copyright-info","label":"Copyright"}]}}