Table 1 Comparison of characteristics and variables between the participants with good and poor hand washing effectiveness

Age, years, median (IQR)

21 (20–22)

21 (20–22)

21 (20–22)

1.00 (0.98–1.03)

Sex, female, n (%)

537/737 (72.9)

327/397 (82.4)

210/340 (61.8)

2.89 (2.07–4.07)

Nursing students, n (%)

658/715 (92.0)

368/391 (94.1)

290/324 (89.5)

1.88 (1.09–3.29)

Step 1, n (%)

Missing

6/744 (0.8)

3/399 (0.8)

3/345 (0.9)

Reference

Completely correct

634/744 (85.2)

339/399 (85.0)

295/345 (85.5)

1.15 (0.21–6.25)

Partially correct

22/744 (3.0)

13/399 (3.3)

9/345 (2.6)

1.44 (0.22–9.46)

Completely wrong

82/744 (11.0)

44/399 (11.0)

38/345 (11.0)

1.16 (0.20–6.58)

Step 2, n (%)

Missing

14/744 (1.9)

5/399 (1.3)

9/345 (2.6)

Reference

Completely correct

434/744 (58.3)

242/399 (60.7)

192/345 (55.7)

2.27 (0.77–7.49)

Partially correct

90/744 (12.1)

48/399 (12.0)

42/345 (12.2)

2.06 (0.66–7.14)

Completely wrong

206/744 (27.7)

104/399 (26.1)

102/345 (29.6)

1.84 (0.61–6.15)

Step 3, n (%)

Missing

125/744 (16.8)

60/399 (15.0)

65/345 (18.8)

Reference

Completely correct

298/744 (40.1)

156/399 (39.1)

142/345 (41.2)

1.19 (0.78–1.81)

Partially correct

60/744 (8.1)

34/399 (8.5)

26/345 (7.5)

1.42 (0.76–2.65)

Completely wrong

261/744 (35.1)

149/399 (37.3)

112/345 (32.5)

1.44 (0.94–2.21)

Step 4, n (%)

Missing

95/744 (12.8)

45/399 (11.3)

50/345 (14.5)

Reference

Completely correct

343/744 (46.1)

192/399 (48.1)

151/345 (43.8)

1.41 (0.90–2.23)

Partially correct

15/744 (2.0)

12/399 (3.0)

3/345 (0.9)

4.44 (1.31–20.42)

Completely wrong

291/744 (39.1)

150/399 (37.6)

141/345 (40.9)

1.18 (0.74–1.88)

Step 5, n (%)

Missing

46/744 (6.2)

17/399 (4.3)

29/345 (8.4)

Reference

Completely correct

474/744 (63.7)

262/399 (65.7)

212/345 (61.4)

2.11 (1.14–4.01)

Partially correct

19/744 (2.6)

10/399 (2.5)

9/345 (2.6)

1.90 (0.64–5.70)

Completely wrong

205/744 (27.6)

110/399 (27.6)

95/345 (27.5)

1.98 (1.03–3.88)

Step 6, n (%)

Missing

58/744 (7.8)

25/399 (6.3)

33/345 (9.6)

Reference

Completely correct

512/744 (68.8)

277/399 (69.4)

235/345 (68.1)

1.56 (0.90–2.71)

Partially correct

38/744 (5.1)

27/399 (6.8)

11/345 (3.2)

3.24 (1.38–7.99)

Completely wrong

136/744 (18.3)

70/399 (17.5)

66/345 (19.1)

1.40 (0.76–2.62)

Step 7, n (%)

Missing

31/744 (4.2)

9/399 (2.3)

22/345 (6.4)

Reference

Completely correct

602/744 (80.9)

328/399 (82.2)

274/345 (79.4)

2.93 (1.37–6.80)

Partially correct

24/744 (3.2)

17/399 (4.3)

7/345 (2.0)

5.94 (1.91–20.35)

Completely wrong

87/744 (11.7)

45/399 (11.3)

42/345 (12.2)

2.62 (1.11–6.60)

Correct duration, seconds, median (IQR)

Step 1

3 (2–5)

3 (2–5)

3 (2–5)

0.95 (0.91–0.99)

Step 2

4 (0–8)

4 (0–7)

4 (0–8)

0.99 (0.96–1.01)

Step 3

0 (0–3)

0 (0–3)

0 (0–4)

0.96 (0.91–1.00)

Step 4

0 (0–6)

2 (0–6)

0 (0–6)

1.00 (0.97–1.03)

Step 5

4 (0–7)

4 (0–7)

4 (0–7)

1.00 (0.97–1.03)

Step 6

4 (0–7)

4 (1–7)

4 (0–7)

0.99 (0.96–1.01)

Step 7

5 (3–8)

5 (3–8)

5 (3–8)

0.99 (0.96–1.02)

Partially correct/completely wrong duration, seconds, median (IQR)

Step 1

0 (0–0)

0 (0–0)

0 (0–0)

1.01 (0.90–1.13)

Step 2

0 (0–3)

0 (0–3)

0 (0–3)

0.98 (0.95–1.01)

Step 3

0 (0–2)

0 (0–2)

0 (0–2)

1.01 (0.96–1.06)

Step 4

0 (0–3)

0 (0–3)

0 (0–4)

0.98 (0.94–1.02)

Step 5

0 (0–1)

0 (0–1)

0 (0–1)

1.00 (0.95–1.05)

Step 6

0 (0–0)

0 (0–0)

0 (0–0)

1.00 (0.96–1.05)

Step 7

0 (0–0)

0 (0–0)

0 (0–0)

1.01 (0.91–1.11)

Rubbing when rinsing hands, n (%)

646/744 (86.8)

361/399 (90.5)

285/345 (82.6)

2.00 (1.30–3.11)

Rinsing time

17 (13-24.25)

18 (13–25)

16 (12–23)

1.02 (1.01–1.04)

One hand washing attempt, n (%)

658/744 (88.4)

379/399 (95.0)

279/345 (80.9)

0.22 (0.13–0.37)

Total duration of step 1–7 regardless of correctness

35 (23–51)

34 (23–50)

36 (23–53)

1.00 (0.99–1.00)

Total duration of correct steps 1–7

27 (14–41)

26 (14–39)

27 (14–44)

1.00 (0.99–1.00)

Total duration of step 1–6 regardless of correctness

29 (19–43)

28 (19–42)

31 (19–45)

0.99 (0.99–1.00)

Total duration of correct steps 1–6

21 (11–32)

20 (11–31)

22 (10–35)

0.99 (0.99–1.00)