Spinal fusion is an aerosol generating procedure

Table 1 Logistic regression analysis of surgical steps of interest for 0.3-0.5 μm/m³ particle counts

Variable	OR	Lower 95%	Upper 95%	Z score	P value
Bovie	10.20	7.80	13.30	16.80	< 0.001
Burring	10.90	6.60	18.00	9.40	< 0.001
Drilling	0.50	0.20	1.10	-1.70	0.099
Bone scalpel	5.90	3.20	10.90	5.70	< 0.001
Max in room	1.40	0.90	2.00	1.60	0.116
Sensor distance	0.03	0.01	0.10	-4.70	< 0.001

OR: Odds ratios.

Table 2 Logistic regression analysis of surgical steps of interest for 1-5 μm/m³ particle counts

Variable	OR	Lower 95%	Upper 95%	Z score	P value
Bovie	2.60	2.00	3.5	6.5	< 0.001
Burring	5.80	3.40	10.2	6.2	< 0.001
Bone scalpel	4.30	2.00	9.3	3.7	0.005
Max in room	1.40	0.90	2.4	1.3	0.179
Sensor distance	0.05	0.01	0.4	-2.9	0.004

OR: Odds ratios.

Table 3 Logistic regression analysis of surgical steps of interest for 10 μm/m³ particle counts

Variable	OR	Lower 95%	Upper 95%	Z score	P value
Bovie	0.3	0.2	0.4	-6.0	< 0.001
Burring	1.0	0.4	2.2	0.0	0.962
Drilling	0.2	0.1	0.7	-2.5	0.011
Bone scalpel	1.3	0.3	5.7	0.4	0.724
Max in room	1.7	0.9	3.5	1.6	0.111
Sensor distance	0.02	0.001	0.2	-3.0	0.003

OR: Odds ratios.