Table 1.
Characteristics of included articles.
| Author and publication date | Country and study design | COVID-19 cases and clinical setting | Time of LUS acquisition | Blinding |
Age (mean or median, years) |
Male cases (%) |
BMI (mean or median, kg/m2) |
Scanned regions, main probe and frequency (Hz) |
|---|---|---|---|---|---|---|---|---|
|
Lu[24], 15/04/2020 |
China, Retrospective cohort |
30, Wards |
Within 24 h | Yes, NA | 52 | 53 | 22.5 | 12, Convex, 5–2 |
|
Yasukawa[25], 24/04/2020 |
United States, Retrospective cohort |
10, Wards |
Within 24 h | No | 53 | 70 | NA | NA, Phased array |
|
Xing[16], 28/04/2020 |
China, NA |
20, Hospital |
After a median time of >5 days | No | NA | 60 | NA | 10, NA |
|
Tan[12], 05/06/2020 |
China, Retrospective case–control |
12, ED |
Within 24 h | No | 61 | 33 | NA | 10, Convex, 3.5–5 |
|
Bar[13], 10/06/2020 |
France, Retrospective case–control |
31, ED |
Within 24 h | Yes, PCR | 67 | 35 | 30.0 | 6, Convex |
|
Pare[26], 19/06/2020 |
United States, Retrospective cohort |
27, ED |
Within 24 h | Yes, PCR | 53 | 59 | 31.7 | NA, Convex |
|
Nouvenne[27], 22/06/2020 |
Italy, NA |
26, Wards |
Within 24 h | Yes, CT | 64 | 54 | NA | 8, Convex, 3.5–5 |
|
Yassa[28], 30/06/2020 |
Turkey, Prospective cohort |
43, Pregnancy ward |
Following a routine fetal assessment | Yes, PCR and clinical data | NA | 0 | NA | 14, Convex, 1–8 |
|
Møller-Sørensen[29], 02/07/2020 |
Denmark, NA |
10, ICU |
Within 24 h | Yes, NA | 53 | 60 | NA | 6, Linear, 12 |
|
Ye[17], 09/07/2020 |
China, Retrospective cohort |
23, Wards |
NA | Yes, Clinical data | 60 | 52 | NA | 12, Convex, 1–5.5 |
|
Deng[30], 14/07/2020 |
China, Retrospective cohort |
128, Hospital |
Within 24 h | Yes, Clinical data | 65 | 59 | NA | 8, Convex, 3.5–5 |
|
Bonadia[31], 15/07/2020 |
Italy, Prospective cohort |
41, ED |
Within 24 h | No | 60 | 78 | NA | 14, Convex, 6 |
|
Dargent[32], 21/07/2020 |
France, NA |
10, ICU |
Within 24 h | No | 56 | 80 | 32.0 | 12, NA |
|
Zhang[18], 22/07/2020 |
China, Retrospective cohort |
28, Hospital |
After a median time of >5 days | No | 60 | 50 | NA | NA, Convex, 1–5 |
|
Yassa[33], 28/07/2020 |
Turkey, Prospective cohort |
23, Pregnancy ward |
Within 24 h | No | NA | 0 | NA | 14, Convex, 1–8 |
|
Veronese[34], 29/07/2020 |
Italy, NA |
48, Nursing home |
Within 5 days | No | 84 | 19 | NA | 12, NA |
|
Zieleskiewicz[35], 29/07/2020 |
France, Retrospective cohort |
100, ED and ICU |
Within 24 h | No | 61 | 65 | NA | 12, NA |
|
Favot[36], 31/07/2020 |
United States, Retrospective cohort |
40, ED |
Within 24 h | Yes, NA | 69 | 60 | 31.0 | 8, Convex |
|
Gaspardone[19], 08/08/2020 |
Italy, Prospective cohort |
70, Rehabilitation unit |
At discharge | No | 68 | 69 | 25.6 | 12, Convex |
|
Ottaviani[37], 12/08/2020 |
France, Prospective cohort |
21, Wards |
NA | Yes, CT and clinical data | 65 | 76 | NA | 12, Convex, 5–18 |
|
Alharthy[38], 14/08/2020 |
Saudi Arabia, Prospective cohort |
89, ICU |
Within 24 h | No | 43 | 84 | 26.5 | 12, Phased array, 2–4 |
|
Thomaz[39], 21/08/2020 |
Brazil, Cross-sectional |
409, Screening tents |
NA | No | 41 | 33 | NA | 12, Linear, 7.5–10 |
|
Lichter[40], 28/08/2020 |
Israel, Retrospective cohort |
120, Hospital |
Within 24 h | Yes, NA | 65 | 62 | NA | 12, Phased array |
|
Iodice[41], 01/09/2020 |
Italy, Prospective cohort |
29, Hospital |
Within 24 h | No. Yes, CT | 60 | 90 | NA | NA, Convex, 3.5–5 |
|
Dini[42], 02/09/2020 |
Italy, NA |
94, Nursing home |
NA | No | NA | NA | NA | 12, Convex, 3.5 |
|
Gil[43], 04/09/2020 |
Spain, Cross-sectional |
27, ED |
Within 24 h | No | 48 | 33 | NA | 13, Convex, 2–5 |
|
Battista[44], 07/09/2020 |
Italy, Prospective cohort |
44, ED |
Within 24 h | Yes, PCR | 66 | 66 | NA | 12, Convex, 2.5–5 |
|
Narinx[45], 10/09/2020 |
Belgium, NA |
15, ED |
Within 24 h | Yes, PCR | 50 | 60 | NA | 6, Convex, 5 |
|
Kalafat[46], 11/09/2020 |
Turkey, Retrospective cohort |
82, Pregnancy ward |
NA | Yes, PCR | 28 | 0 | 27.6 | 6, NA |
|
Li[47], 15/09/2020 |
China, Retrospective cohort |
91, Hospital |
NA | No | 59 | 68 | NA | 12, Linear, 4–12 |
|
Castelao[48], 16/09/2020 |
Spain, Prospective cohort |
63, Wards |
Within 5 days | Yes, Chest radiography and clinical data, but not PCR status | 61 | 68 | NA | 12, Convex, 2–5 |
|
Cocconcelli[20], 16/09/2020 |
Italy, Retrospective cohort |
102, Hospital |
After a median time of >5 days | No | 68 | 74 | 25.0 | 12, Convex, 1–8 |
|
Brahier[49], 17/09/2020 |
Switzerland, Prospective cohort |
80, ED |
Within 24 h | Yes, Clinical data | 62 | 58 | NA | 10, NA |
|
Ramos-Hernández[50], 21/09/2020 |
Spain, Prospective cohort |
44, Wards |
Within 5 days | No | 69 | 68 | NA | 8, Convex |
|
Zhu[51], 21/09/2020 |
China, Prospective cohort |
27, Hospital |
Within 5 days | No | 63 | 59 | NA | 10, Convex, 1.5–5 |
|
Rojatti[52], 25/09/2020 |
Italy, Retrospective cohort |
41, ICU |
Within 24 h | No | 62 | 78 | 26.7 | 8, Convex |
|
Marggrander[23], 01/10/2020 |
Germany, Retrospective cohort |
17, Hospital |
NA | No | 51 | 65 | NA | NA, Convex, 3–5 |
|
Bosso[14], 03/10/2020 |
Italy, NA |
26, ED |
NA | Yes, PCR | 66 | 69 | NA | 12, Linear |
|
Colombi[53], 08/10/2020 |
Italy, Retrospective cohort |
341, ED |
Within 24 h | No | NA | NA | NA | 12, Convex, 1–8 |
|
Haaksma[54], 08/10/2020 |
Netherlands, NA |
61, ICU |
NA | Yes, Clinical data | 66 | 90 | 28.5 | 12, Linear, 5–10 |
|
Pivetta[55], 12/10/2020 |
Italy, Prospective cohort |
107, ED |
Within 24 h | Yes, PCR | 63 | 55 | NA | 12, Convex, 3–5 |
|
Lieveld[56], 15/10/2020 |
Netherlands, Prospective cohort |
86, ED |
Within 24 h | Yes, PCR and CT | 63 | 58 | NA | 12, NA |
|
Zhu[21], 16/10/2020 |
China, Retrospective cohort |
48, Hospital |
After a median time of >5 days | Yes, CT and clinical data | 63 | 54 | NA | 12, Convex, 3.5–5 |
|
Bosevski[57], 22/10/2020 |
Macedonia, NA |
17, ICU |
NA | No | 57 | NA | NA | NA |
|
Sorlini[58], 22/10/2020 |
Italy, Retrospective cohort |
287, ED |
Within 24 h | No | NA | NA | NA | 12, NA |
|
Jalil[59], 26/10/2020 |
United States, Retrospective cohort | 36, Hospital |
Within 24 h | Yes, PCR, clinical data and chest radiography | 63 | 53 | 30.5 | 8, NA |
| Gibbons[60], 29/10/2020 | United States, Prospective cohort |
83, ED |
Within 24 h | No | 56 | 43 | NA | 8, NA |
|
Li[61], 03/11/2020 |
China, NA |
42, ICU |
Within 24 h | No | 68 | 43 | NA | NA, Convex, 5 |
|
Zotzmann[62], 03/11/2020 |
Germany, Retrospective cohort |
20, ICU |
NA | Yes, CT | 62 | 70 | 28.3 | 8, Convex, 5–1 |
|
Perrone[63], 06/11/2020 |
Italy, NA |
52, Wards |
Within 24 h | Yes, Clinical data | 64 | 54 | 25.3 | 14, Convex, 3.5–5 |
|
Alharthy[64], 13/11/2020 |
Saudi Arabia, Prospective cohort |
171, ICU |
Within 24 h | No | 47 | 79 | 26.4 | 12, Phased array, 2–4 |
|
Haak[65], 18/11/2020 |
Netherlands, Prospective cohort |
24, ED |
Within 24 h | Yes, PCR and clinical data | NA | NA | NA | 12, Convex, 2–6 |
|
Allegorico[66], 01/12/2020 |
Italy, Retrospective cohort |
42, ED |
Within 24 h | No | 69 | 69 | NA | 12, NA |
|
Recinella[67], 03/12/2020 |
Italy, NA |
37, Wards |
Within 24 h | No | 82 | 51 | 23.7 | 12, Linear, 5–8 |
|
Schmid[68], 07/12/2020 |
Germany, Retrospective cohort |
39, ED |
Within 24 h | Yes, PCR, clinical data and CT | 61 | 56 | 26.3 | 12, NA |
|
Zanforlin[69], 07/12/2020 |
Italy, Retrospective cohort |
46, ED |
Within 24 h | No | 60 | 57 | NA | 20, Convex, 5–2 |
|
Wangüemert Pérez[70], 17/12/2020 |
Spain, Retrospective cohort |
45, Wards |
Within 24 h | No | 82 | 44 | NA | 12, Convex, 3–5 |
|
Ji[22], 22/12/2020 |
China, Prospective cohort |
280, Hospital |
After a median time of >5 days | Yes, Clinical data | 55 | 50 | 23.1 | 12, Convex, 1–6 |
|
Speidel[15], 25/12/2020 |
Switzerland, Prospective cohort |
11, Wards |
Within 24 h | Yes, PCR and clinical data | 76 | 73 | NA | 12 Convex, 4 |
|
Ibrahim[71], 04/01/2021 |
Kuwait, Prospective cohort |
77, ICU |
Within 24 h | Yes, PCR | 53 | 83 | NA | 12, Convex, 3.5 |
|
Bock[72], 07/01/2021 |
Denmark, Prospective cohort |
12, ED |
Within 24 h | Yes, PCR and chest radiography but not to clinical data | 68 | 58 | NA | 14, Convex, 1–5 |
|
Garcia de Alencar[73], 11/01/2021 |
Brazil, Prospective cohort |
180, ED |
Within 24 h | Yes, CT and clinical data | 60 | 58 | NA | 12, Convex, 2–5 |
|
Boero[74], 24/01/2021 |
Italy, Retrospective cohort |
274, ED |
Within 5 days | No | NA | NA | NA | 12, Convex, 2–9 |
|
Avdeev[75], 25/01/2021 |
Russia, Prospective cohort |
22, Wards |
NA | Yes, Clinical data | 49 | 73 | 28.7 | 14, NA |
|
Heldeweg[76], 25/01/2021 |
Netherlands, Prospective cohort |
34, ICU |
NA | Yes, CT | 63 | 88 | 28.2 | 12, Linear, 10–5 |
|
Seiler[77], 26/01/2021 |
Sweden, Prospective cohort |
72, Hospital |
Within 5 days | No | 65 | 60 | 28.0 | 12, Convex, 2–6 |
*BMI: Body Mass Index; ED: Emergency Department; ICU: Intensive Care Unit; NA: Not Available.