Table 2.
Results of multivariable logistic regression analysis for seven different models on mask-wearing and Rt values accounting for various factors
| Model 1: association with Rt, OR (95% CI) | Model 2: weighted sample, OR (95% CI) | Model 3: association with Rt, OR (95% CI) | Model 4: alternative mask definition 1, OR (95% CI) | Model 5: alternative mask definition 2, OR (95% CI) | Model 6: accounting for transmission before the start of the study, OR (95% CI) | Model 7: with interaction term, OR (95% CI) | |
|---|---|---|---|---|---|---|---|
| Composite percentage of respondents “very likely” to wear a mask | 1·14* (1·07–1·20) | 1·13* (1·07–1·20) | 1·10* (1·04–1·15) | .. | .. | 1·14* (1·08–1·21) | 1·17† (1·05–1·32) |
| Time trend (measured by week) | 1·36* (1·17–1·58) | 1·35* (1·16–1·57) | 1·27* (1·11–1·45) | 1·37* (1·18–1·59) | 1·40* (1·20–1·63) | 1·38* (1·18–1·60) | 1·35* (1·17–1·56) |
| Physical distancing (measured by proxy) | 1·42* (1·16–1·74) | 1·43* (1·17–1·75) | 1·37† (1·13–1·66) | 1·41* (1·15–1·72) | 1·52* (1·24–1·86) | 1·39† (1·13–1·72) | 1·77 (0·99–3·15) |
| Race other than White | 0·94* (0·91–0·96) | 0·94* (0·91–0·97) | 0·94* (0·92–0·97) | 0·94* (0·91–0·96) | 0·96* (0·93–0·98) | 0·93* (0·90–0·96) | 0·95* (0·92–0·97) |
| Density (measured by 1000 people per square mile) | 0·09† (0·02–0·39) | 0·08* (0·02–0·31) | 0·30‡ (0·10–0·88) | 0·09† (0·02–0·39) | 0·08* (0·02–0·32) | 0·03* (0·01–0·15) | 0·10† (0·03–0·41) |
| Percentage of respondents “very likely” to wear a mask with family or friends | .. | .. | .. | 1·14* (1·08–1·21) | .. | .. | .. |
| Percentage of respondents “very likely” to wear a mask when grocery shopping | .. | .. | .. | .. | 1·07† (1·02–1·12) | .. | .. |
| State peak Rt (March–May) | .. | .. | .. | .. | .. | 2·60* (1·49–4·56) | .. |
| Mask wearing and physical distancing | .. | .. | .. | .. | .. | .. | 0·99 (0·98–1·01) |
| Total number of observations (week × state) | 376 | 379 | 378 | 376 | 382 | 381 | 382 |
| Akaike information criterion | 347·78 | 352·83 | 383·84 | 347·10 | 366·59 | 346·94 | 363·63 |
| Pseudo R2 | 0·39 | 0·38 | 0·31 | 0·40 | 0·35 | 0·41 | 0·37 |
Each N represents one observation of one state on a single week. Model 1 reports the association of the outcome of community transmission control (Rt<1) with the percentage of survey respondents stating that they were “very likely” to wear a face mask to the grocery store and to visit family and friends, aggregated by state and week. Model 1 controls for a weekly time trend, physical distancing (measured by relative Google mobility residential time), percentage non-White, and population density. We evaluated the association using survey weights (model 2), alternative estimators of Rt (model 3), and alternative definitions of mask usage (models 4 and 5). Model 6 accounts for each states' peak Rt before the start of the study, and model 7 includes an interaction of mask wearing with physical distancing. OR=odds ratio. Rt=instantaneous reproductive number.
p<0·001.
p<0·01.
p<0·05.