Table 1.
Description [n (%)] of the characteristics of the study population and early life indoor factors according to the study design.
| Study population | Random sample | Enrichment cases | |
|---|---|---|---|
| (hyperactivity/inattention age 15) | |||
| N = 226 | N = 189 | N = 37 | |
| Socio-demographic factors | |||
| Sex (girl) | 109 (48.2) | 94 (49.7) | 15 (40.5) |
| Parental education (>10 years) | 162 (72.0) | 135 (71.8) | 27 (73.0) |
| Study city (Munich) | 146 (64.6) | 118 (62.4) | 28 (75.7) |
| Hyperactivity/inattention | |||
| 10 years old* | 23 (11.7) | 18 (10.9) | 5 (16.1) |
| 15 years old | 50 (22.1) | 13 (6.9) | 37 (100.0) |
| Early life bedroom floor dust samples | |||
|
Microbial diversity measures (median and p25–p75)** | |||
| Bacteria | |||
| Number of observed OTUs | 302 (254–366) | 301 (253–369) | 305 (267–341) |
| Chao1 | 767 (633–899) | 761 (633–917) | 789 (622–859) |
| Shannon | 6.32 (5.81–7.01) | 6.35 (5.78–7.10) | 6.31 (5.94–6.65) |
| Simpson | 0.95 (0.92–0.97) | 0.95 (0.92–0.97) | 0.94 (0.92–0.96) |
| Fungi | |||
| Number of observed OTUs | 164 (125–197) | 167 (128–198) | 149 (108–190) |
| Chao1 | 283 (235–353) | 285 (235–360) | 273 (236–313) |
| Shannon | 5.22 (4.16–5.97) | 5.31 (4.32–5.97) | 4.74 (3.48–5.92) |
| Simpson | 0.92 (0.83–0.96) | 0.93 (0.84–0.96) | 0.89 (0.73–0.95) |
| Season of dust sampling | |||
| Winter | 61 (27.0) | 55 (29.3%) | 6 (16.7%) |
| Spring | 60 (26.6) | 50 (26.6%) | 10 (27.8%) |
| Summer | 44 (19.5) | 39 (20.7%) | 4 (11.1%) |
| Autumn | 61 (27.0) | 44 (23.4%) | 16 (44.4%) |
| Early life indoor factors | |||
| Pet ownership | 59 (26.2) | 49 (26.2%) | 9 (25.0%) |
| Siblings at birth | 96 (42.5) | 75 (39.9%) | 20 (55.6%) |
| Indoor smoking | 37 (16.4) | 28 (14.9%) | 9 (25.0%) |
| Mold at home | 10 (4.4) | 8 (4.3%) | 2 (5.6%) |
p25: 25th percentile; p75:75th percentile. Bold indicates p-value < 0.05 (Chi2 tests for categorical variables, and Wilcoxon tests for continuous variables). N total number of observations, n number of cases in each category, % percentage of characteristic in each category. *N = 196 (random sample N = 165; enrichment sample N = 31). **Bacteria: N = 224 (random N = 188; enrichment N = 36); fungi N = 218 (random N = 182; enrichment N = 36).