Effect of high-efficiency particulate air filter on children with asthma: a systematic review protocol of RCTs

Introduction Asthma has been classified as a major non-communicable disease by the WHO. With the worsening air quality index worldwide, the burden of asthma has increased specifically in children. The focus of the management strategy of asthma has shifted from traditional pharmacological treatments towards non-pharmacological preventive and control therapy in recent decades. The use of high-efficiency particulate air (HEPA) filters is one of the methods to achieve that, despite extensive research, the efficacy of HEPA filters in this context of effectiveness and usage guidelines remains unclear. Our study aims to examine the effect of HEPA filters in (1) reducing clinical visits or hospital admissions or the number of exacerbation events, (2) reducing asthma symptoms, (3) increasing asthma symptom-free days, (4) reducing indoor particulate matter 2.5 levels for children with asthma aged 5-17 years and (5) improving quality of life.Methods We will conduct a systematic review using MEDLINE, Google Scholar and Scopus as databases, article selection is planned to be restricted to randomised controlled trials only (2002-2025). We are following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines developed specifically for the protocol(s). Two reviewers will screen the studies independently and assess study quality using the Cochrane Risk of Bias Tool for Randomised Trials, V.2. The results of outcome measure(s) will be summarised in tables. If the studies are sufficient, we will also perform a quantitative analysis by creating forest plots and subgroup analysis will be performed if required. Lastly, publication bias will be assessed using a funnel plot and Egger's test and reported accordingly.Ethics and dissemination We will conduct a systematic review, therefore there is no need for a formal ethical review. After successful completion, our results will be published in a peer-reviewed journal.PROSPERO registration number CR42024494949.