Table 2.
Summary of PNC measurements during HEPA and sham filtration
| HEPA | Sham | I/O Ratioa | Reduction in PNC during HEPA compared to shamb | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Participant ID | Order | Exposure | Median PNC | Mean PNC | Median PNC | Mean PNC | Sham | HEPA | % | Abs. |
| P01 | Hepa-1st | Indoor | 4500 | 14000 | 7900 | 20000 | 0.88 | 0.38 | 43% | 3400 |
| Outdoor | 12000 | 13000 | 9000 | 11000 | ||||||
| P02 | Sham-1st | Indoor | 1300 | 17000 | 9100 | 34000 | 0.83 | 0.16 | 86% | 7800 |
| Outdoor | 7900 | 9400 | 11000 | 13000 | ||||||
| P03 | Hepa-1st | Indoor | 3700 | 11000 | 8400 | 31000 | 0.88 | 0.47 | 56% | 4700 |
| Outdoor | 7800 | 9100 | 9600 | 12000 | ||||||
| P04 | Sham-1st | Indoor | 2000 | 7200 | 5600 | 12000 | 0.62 | 0.27 | 64% | 3600 |
| Outdoor | 7400 | 8600 | 9000 | 11000 | ||||||
| P05 | Hepa-1st | Indoor | 1800 | 13000 | 7200 | 32000 | 0.60 | 0.18 | 75% | 5400 |
| Outdoor | 10000 | 14000 | 12000 | 17000 | ||||||
| P06 | Sham-1st | Indoor | 3700 | 38000 | 12000 | 68000 | 0.86 | 0.21 | 69% | 8300 |
| Outdoor | 18000 | 20000 | 14000 | 17000 | ||||||
| P07 | Sham-1st | Indoor | 7600 | 16000 | 15000 | 25000 | 1.00 | 0.94 | 49% | 7400 |
| Outdoor | 8100 | 13000 | 15000 | 19000 | ||||||
| P08 | Sham-1st | Indoor | 3600 | 9800 | 7900 | 17000 | 0.42 | 0.23 | 54% | 4300 |
| Outdoor | 16000 | 19000 | 19000 | 22000 | ||||||
| P10 | Hepa-1st | Indoor | 3400 | 11000 | 5800 | 16000 | 0.62 | 0.28 | 41% | 2400 |
| Outdoor | 12000 | 15000 | 9400 | 13000 | ||||||
| P11 | Hepa-1st | Indoor | 4500 | 17000 | 4300 | 10000 | 0.61 | 0.60 | −5% | −200 |
| Outdoor | 7500 | 9200 | 7100 | 9300 | ||||||
| P12 | Sham-1st | Indoor | 1400 | 5900 | 3200 | 10000 | 0.41 | 0.15 | 56% | 1800 |
| Outdoor | 9400 | 13000 | 7900 | 11000 | ||||||
| P13 | Hepa-1st | Indoor | 1500 | 24000 | 6500 | 40000 | 0.66 | 0.14 | 77% | 5000 |
| Outdoor | 11000 | 12000 | 9900 | 12000 | ||||||
| P14 | Sham-1st | Indoor | 2600 | 11000 | 5400 | 19000 | 0.36 | 0.17 | 52% | 2800 |
| Outdoor | 15000 | 17000 | 15000 | 18000 | ||||||
| P16 | Hepa-1st | Indoor | 1700 | 2600 | 5500 | 7300 | 0.42 | 0.11 | 69% | 3800 |
| Outdoor | 15000 | 16000 | 13000 | 15000 | ||||||
| P17 | Sham-1st | Indoor | 2200 | 12000 | 12000 | 19000 | 0.75 | 0.13 | 82% | 9800 |
| Outdoor | 17000 | 20000 | 16000 | 22000 | ||||||
| P19 | Sham-1st | Indoor | 1000 | 3200 | 3900 | 7100 | 0.35 | 0.11 | 74% | 2900 |
| Outdoor | 9400 | 13000 | 11000 | 15000 | ||||||
| P20 | Hepa-1st | Indoor | 1000 | 11000 | 3500 | 13000 | 0.35 | 0.08 | 71% | 2500 |
| Outdoor | 13000 | 18000 | 10000 | 12000 | ||||||
| P21 | Sham-1st | Indoor | 2000 | 15000 | 4900 | 14000 | 0.45 | 0.22 | 59% | 2900 |
| Outdoor | 9000 | 12000 | 11000 | 14000 | ||||||
| P22 | Sham-1st | Indoor | 500 | 4000 | 3300 | 16000 | 0.30 | 0.08 | 85% | 2800 |
| Outdoor | 6000 | 7600 | 11000 | 14000 | ||||||
| P23 | Hepa-1st | Indoor | 1000 | 8900 | 4300 | 17000 | 0.54 | 0.12 | 77% | 3300 |
| Outdoor | 8500 | 12000 | 8000 | 11000 | ||||||
| P24 | Hepa-1st | Indoor | 3600 | 9000 | 5400 | 8700 | 0.49 | 0.26 | 33% | 1800 |
| Outdoor | 14000 | 19000 | 11000 | 15000 | ||||||
| P25 | Sham-1st | Indoor | 1900 | 7800 | 4700 | 16000 | 0.49 | 0.17 | 60% | 2800 |
| Outdoor | 11000 | 14000 | 9600 | 14000 | ||||||
| P26 | Hepa-1st | Indoor | 3500 | 9500 | 5600 | 16000 | 0.43 | 0.25 | 38% | 2100 |
| Outdoor | 14000 | 18000 | 13000 | 16000 | ||||||
a
Ratio of median indoor measurement to median outdoor measurement.
b
(median indoor measurement during sham - median indoor measurement during HEPA)/median indoor measurement during sham.