Table 1. Characteristics of the selected studies (clinical trials).
| Bibliography Rank | Authors and (Citation number) | Year of publication | Study design | Total experimental n. | Vaccinated pre (exp) n. (%) | Vaccinated post (exp) n. (%) | Total control n. | Vaccinated pre n. (%) | Vaccinated post n. (%) | JADAD score 1 (1–5) | JADAD score 2 (1–5) | JADAD score 3 (1–5) definitive |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |
Rothan-Tondeur et al.21 |
2010 |
cluster-RCT |
1,201 |
336 (28%) |
408 (34%) |
1144 |
286 (25%) |
366 (32%) |
-1 |
-1 |
-1 |
| 2 |
Hayward et al.**5 |
2006 |
cluster-RCT (2003–2004) |
1,610 |
|
570 (35.4%) |
1674 |
|
84 (5%) |
4 |
3 |
4 (resolving) |
| 2 |
Hayward et al.**5 |
2006 |
cluster-RCT (2004–2005) |
1,726 |
|
527 (30.5%) |
1766 |
|
67 (3.8%) |
|
|
4 (resolving) |
| 3 |
Dey et al.14 |
2001 |
cluster-RCT |
PHCT*: 457 |
|
100 (21.9%) |
PHCT*: 395 |
|
83 (21%) |
4 |
3 |
4 (resolving) |
| |
|
|
|
NH*: 768 |
|
78 (10.2%) |
NH*: 1364 |
|
77 (5.6%) |
|
|
|
| 4 |
Kimura et al.15 |
2007 |
cluster-RCT |
Ed*: 821 |
240 (29%) |
298 (34%) |
1517 |
467 (31%) |
450 (28%) |
4 |
4 |
4 |
| |
|
|
|
(vacc.day) 832 |
292 (35%) |
410 (46%) |
|
|
|
|
|
|
| |
|
|
|
(ed + vacc. Day) 754 |
295 (39%) |
439 (53%) |
|
|
|
|
|
|
| 5 |
Abramson et al.16 |
2010 |
cluster-RCT |
163 |
44 (27%) |
86 (52.8%) |
181 |
36 (19.9%) |
48 (26.5%) |
3 |
4 |
4 (resolving) |
| 6 |
Ohrt et al.19 |
1992 |
cluster-RCT |
180 |
50 |
103 |
175 |
48 |
85 |
2 |
2 |
2 |
| 7 |
Lemaitre et al.18 |
2009 |
cluster- RT |
989 |
198 |
678 |
1015 |
200 |
|
4 |
4 |
4 |
| 8 |
Tannenbaum et al.22 |
1993 |
cluster-CT |
135 |
23 |
35 |
133 |
22 |
13 |
-1 |
-1 |
-1 |
| 9 |
Looijmans I et al.17 |
2009 |
cluster-RT |
Tot. 3,086 (20%) |
|
|
Tot. 3,550 (21%) |
|
|
4 |
4 |
4 |
| (1) All HCWs Vaccinated |
774/3085 (25.1%) |
|
|
582/3,550 (16.4%) |
|
|
|
|||||
| (2) Physician Vaccinated |
43/70 (61.4%) |
|
|
37/75 (49.3%) |
|
|
|
|||||
| (3) Nurses Vaccinated |
94/179 (52.5%) |
|
|
79/287 (27.5%) |
|
|
|
|||||
| (4) Nursing assistants Vaccinated |
429/2095 (20.5%) |
|
|
296/2,138 (13.8%) |
|
|
|
|||||
| 10 | Doratotaj et al.20 | 2008 |
cluster-RT |
200 |
|
tot. 78 (39%) |
200 |
|
tot. 76 (38%) |
1 |
1 |
1 |
| |
|
200 |
|
tot. 84 (42%) |
200 |
|
|
|
|
|
||
| 200 | tot. 89 (44,5%) | 200 |
* PHCT, Pshycians; NH, Nurse; Ed, Educational; **Hayward et al. (2006) The study delineated a pair matched cluster randomized controlled trial during the winters of 2003–4 and 2004–5. We considered the study as two in one and the study have a different and specific context in comparison to the others. ***RCT, randomized controlled trial; CT, controlled trial; RT, randomized trial.