Trial Outcomes & Findings for Bronchiolitis Recovery and the Use of High Efficiency Particulate Air (HEPA) Filters (NCT NCT05615870)

NCT ID: NCT05615870

Last Updated: 2025-10-02

Results Overview

An SFD is defined as a 24-hour period without coughing, wheezing, or trouble breathing

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

230 participants

Primary outcome timeframe

24 Weeks

Results posted on

2025-10-02

Participant Flow

Two enrolled participants terminated the study prior to randomization due to withdrawal of consent and ineligibility.

Participant milestones

Participant milestones
Measure
Intervention Group (Active Filter)
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Overall Study
STARTED
113
115
Overall Study
COMPLETED
100
94
Overall Study
NOT COMPLETED
13
21

Reasons for withdrawal

Reasons for withdrawal
Measure
Intervention Group (Active Filter)
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Overall Study
Lost to Follow-up
10
13
Overall Study
Physician Decision
2
0
Overall Study
Withdrawal by Subject
0
2
Overall Study
Protocol Violation
0
3
Overall Study
Unable to complete study activities after moving residences
0
2
Overall Study
Terminated from the experimental or control intervention only and continued with the study
1
0
Overall Study
The participant thought the study was done and shipped the devices back.
0
1

Baseline Characteristics

Bronchiolitis Recovery and the Use of High Efficiency Particulate Air (HEPA) Filters

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Intervention Group (Active Filter)
n=113 Participants
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=115 Participants
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Total
n=228 Participants
Total of all reporting groups
Age, Continuous
4.0 Months
STANDARD_DEVIATION 2.9 • n=5 Participants
4.3 Months
STANDARD_DEVIATION 2.9 • n=7 Participants
4.1 Months
STANDARD_DEVIATION 2.9 • n=5 Participants
Sex: Female, Male
Female
41 Participants
n=5 Participants
49 Participants
n=7 Participants
90 Participants
n=5 Participants
Sex: Female, Male
Male
72 Participants
n=5 Participants
66 Participants
n=7 Participants
138 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
16 Participants
n=5 Participants
12 Participants
n=7 Participants
28 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
94 Participants
n=5 Participants
102 Participants
n=7 Participants
196 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
3 Participants
n=5 Participants
1 Participants
n=7 Participants
4 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
10 Participants
n=5 Participants
6 Participants
n=7 Participants
16 Participants
n=5 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
1 Participants
n=5 Participants
2 Participants
n=7 Participants
3 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
13 Participants
n=5 Participants
16 Participants
n=7 Participants
29 Participants
n=5 Participants
Race (NIH/OMB)
White
70 Participants
n=5 Participants
74 Participants
n=7 Participants
144 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
16 Participants
n=5 Participants
14 Participants
n=7 Participants
30 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
3 Participants
n=5 Participants
3 Participants
n=7 Participants
6 Participants
n=5 Participants
Rurality (RUCA code)
Metropolitan
79 Participants
n=5 Participants
78 Participants
n=7 Participants
157 Participants
n=5 Participants
Rurality (RUCA code)
Micropolitan
9 Participants
n=5 Participants
14 Participants
n=7 Participants
23 Participants
n=5 Participants
Rurality (RUCA code)
Small town
5 Participants
n=5 Participants
12 Participants
n=7 Participants
17 Participants
n=5 Participants
Rurality (RUCA code)
Rural
19 Participants
n=5 Participants
9 Participants
n=7 Participants
28 Participants
n=5 Participants
Rurality (RUCA code)
Unknown
1 Participants
n=5 Participants
2 Participants
n=7 Participants
3 Participants
n=5 Participants

PRIMARY outcome

Timeframe: 24 Weeks

Population: The analysis population included all participants who were randomized to either HEPA filtration (intervention group) or inactive filter unit (control group) with available outcome data

An SFD is defined as a 24-hour period without coughing, wheezing, or trouble breathing

Outcome measures

Outcome measures
Measure
Intervention Group (Active Filter)
n=110 Participants
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=109 Participants
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Number of Caregiver-reported Symptom-free Days (SFDs)
118.01 Days
Standard Deviation 42.66
112.60 Days
Standard Deviation 46.33

SECONDARY outcome

Timeframe: 24 weeks

Population: The analysis population included all participants who are randomized to either HEPA filtration (intervention group) or inactive filter unit (control group) with available data of Unscheduled Healthcare Visits

Caregiver reported number of hospitalizations, emergency department or urgent care visits, other unscheduled medical visits, and the sum of total counts of all metrics for respiratory complaints

Outcome measures

Outcome measures
Measure
Intervention Group (Active Filter)
n=109 Participants
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=109 Participants
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Number of Hospitalizations, Emergency Department or Urgent Care Visits or Other Unscheduled Medical Visits for Respiratory Complaints
Emergency Department (ED) or Urgent Care (UC) visits
0.68 Visits
Standard Deviation 1.25
0.68 Visits
Standard Deviation 1.32
Number of Hospitalizations, Emergency Department or Urgent Care Visits or Other Unscheduled Medical Visits for Respiratory Complaints
Other unscheduled healthcare visits (UHVs) for respiratory complaints
1.11 Visits
Standard Deviation 1.65
1.48 Visits
Standard Deviation 1.99
Number of Hospitalizations, Emergency Department or Urgent Care Visits or Other Unscheduled Medical Visits for Respiratory Complaints
Hospitalizations
0.28 Visits
Standard Deviation 0.91
0.16 Visits
Standard Deviation 0.60
Number of Hospitalizations, Emergency Department or Urgent Care Visits or Other Unscheduled Medical Visits for Respiratory Complaints
A sum of counts (or total counts) of all metrics
2.06 Visits
Standard Deviation 2.83
2.31 Visits
Standard Deviation 2.84

SECONDARY outcome

Timeframe: 24 weeks

Population: Participants who were randomized to either HEPA filtration (intervention group) or inactive filter unit (control group) and answered the quality of life (QOL) survey.

QOL score is measured by the Pediatric Quality of Life Inventory TM (PedsQLTM) Infants Scales questionnaire. The scores are reverse-scored and linearly transformed to a 0-100 scale. Higher scores mean a better outcome.

Outcome measures

Outcome measures
Measure
Intervention Group (Active Filter)
n=100 Participants
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=95 Participants
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Total Quality of Life (QOL) Score
81.34 Scores on a scale
Standard Deviation 9.99
82.13 Scores on a scale
Standard Deviation 10.68

SECONDARY outcome

Timeframe: 24 weeks

Population: Participants who were randomized to either HEPA filtration (intervention group) or inactive filter unit (control group) with available PM2.5 data

PM2.5 levels (Particulate Matter ≤ 2.5 micrometers in diameter) are measured by in-home monitors and scaled to unit of micrograms per cubic meter per week. Higher levels mean a worse outcome.

Outcome measures

Outcome measures
Measure
Intervention Group (Active Filter)
n=102 Participants
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=100 Participants
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Average Particulate Matter (PM2.5) Levels
Common room
10.70 µg/m³/week
Standard Deviation 15.91
15.27 µg/m³/week
Standard Deviation 16.86
Average Particulate Matter (PM2.5) Levels
Sleep space
11.08 µg/m³/week
Standard Deviation 18.77
21.45 µg/m³/week
Standard Deviation 33.14
Average Particulate Matter (PM2.5) Levels
Average of common room and sleep space
10.66 µg/m³/week
Standard Deviation 15.53
17.96 µg/m³/week
Standard Deviation 21.35

Adverse Events

Intervention Group (Active Filter)

Serious events: 17 serious events
Other events: 7 other events
Deaths: 0 deaths

Control Group (No Filter)

Serious events: 12 serious events
Other events: 11 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Intervention Group (Active Filter)
n=113 participants at risk
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=115 participants at risk
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Respiratory, thoracic and mediastinal disorders
Medical or emergency department/urgent care visit for respiratory complaint
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Trouble breathing
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.87%
1/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Wheeze
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Other - bronchiolitis, hospitalization for hypoxia & increased work of breathing, and respiratory di
4.4%
5/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Other - Respiratory Distress, Reactive airway disease with wheezing, Hypoxemia and nasal congestion
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
4.3%
5/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Infections and infestations
Other - Bronchiolitis
5.3%
6/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
4.3%
5/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Nervous system disorders
Other - seizure like activity
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Surgical and medical procedures
VSD repair surgery
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Injury, poisoning and procedural complications
Other - Patient had bilateral ear tubes placed
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Metabolism and nutrition disorders
Other - Hospitalization due to failure to thrive
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.87%
1/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)

Other adverse events

Other adverse events
Measure
Intervention Group (Active Filter)
n=113 participants at risk
The intervention group will use two Winix 5500-2 HEPA filtration units (Appendix A) (https://winixamerica.com/product/5500-2/). One will be placed in the child's sleep space and one will be placed in another common room with both units running continuously on the "high" (i.e., level 3 / second from highest) setting. Each unit is 8.2 x 15.0 x 23.6 inches, and verified for a 360 sq. foot room. If a home is too small to accommodate 2 Winix units (for example, a single room residence'), one Winix unit may be used for the study. Additional features beyond HEPA and carbon filter, include plasmawave technology to reduce volatile organic compounds and odors. The plasmawave feature will be turned off to avoid ozone production. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Control Group (No Filter)
n=115 participants at risk
The control group will use identical-appearing Winix 5500-2 units and identical setup procedures as described above, but with no HEPA or carbon filters. Winix 5500-2 HEPA filtration units: To determine if use of a HEPA filtration unit home intervention reduces the respiratory symptom burden (symptom-free days; SFD) for 24 weeks compared to a use of a control unit.
Respiratory, thoracic and mediastinal disorders
Other - Subglottic stenosis requiring micro laryngoscopy and bronchoscopy / Reactive Airway Disease
3.5%
4/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Medical or emergency department/urgent care visit for respiratory complaint
1.8%
2/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.00%
0/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Respiratory, thoracic and mediastinal disorders
Other - Rhinitis, Coughing, Wheezing
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
4.3%
5/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Infections and infestations
Other - Cough
0.88%
1/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.87%
1/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Immune system disorders
Other- Viral induced asthma
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
1.7%
2/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Gastrointestinal disorders
Other - Constipation issues that required emergency room visit
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
0.87%
1/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
Nervous system disorders
Other - Seizure
0.00%
0/113 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)
1.7%
2/115 • From November 24, 2022, to May 22, 2024 (1 year, 5.9 months)

Additional Information

Jing Jin

University of Arkansas for Medical Sciences

Phone: 501-214-2236

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place