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Table. 2.

Relationship between Roche’s reagent HBsAg test COI value and percent neutralization tests performed by institution type

COI Institution type
Health screening center (N=3) Secondary-care hospital (N=5) Tertiary-care hospital (N=4) Total (N=12)
No. sample (sample%) No. NT (NT%) NT Pos (Pos%) No. sample (sample%) No. NT (NT%) NT Pos (Pos%) No. sample (sample%) No. NT (NT%) NT Pos (Pos%) No. sample (sample%) No. NT (NT%) NT Pos (Pos%)
COI <0.9 455,125 (97.4) 4 (<0.1) 2 (50.0) 105,460 (97.1) 0 (0) NA 177,743 (95.6) 1 (<0.1) 0 738,328 (96.9) 5 (<0.1) 2 (40.0)
0.9≤ COI <1.0 64 (0.0) 18 (28.1) 9 (50.0) 29 (0.0) 6 (20.7) 1 (16.7) 38 (0.0) 8 (21.1) 2 (25.0) 131 (0.0) 32 (24.4) 12 (37.5)
1.0≤ COI <5 500 (0.1) 345 (69.0) 107 (31.0) 181 (0.2) 121 (66.9) 68 (56.2) 329 (0.2) 282 (85.7) 165 (58.5) 1,010 (0.1) 748 (74.1) 340 (45.5)
5≤ COI <10 107 (0.0) 55 (51.4) 42 (76.4) 38 (0.0) 20 (52.6) 17 (85.0) 92 (0.0) 64 (69.6) 58 (90.6) 237 (0.0) 139 (58.6) 117 (84.2)
10≤ COI <20 79 (0.0) 25 (31.6) 25 (100.0) 42 (0.0) 6 (14.3) 6 (100.0) 109 (0.1) 4 (3.7) 4 (100.0) 230 (0.0) 35 (15.2) 35 (100.0)
20≤ COI <30 58 (0.0) 18 (31.0) 15 (83.3) 19 (0.0) 1 (5.3) 1 (100.0) 55 (0.0) 1 (1.8) 1 (100.0) 132 (0.0) 20 (15.2) 17 (85.0)
30≤ COI <40 31 (0.0) 1 (3.2) 1 (100.0) 18 (0.0) 0 NA 47 (0.0) 1 (2.1) 1 (100.0) 96 (0.0) 2 (2.1) 2 (100.0)
40≤ COI <50 22 (0.0) 0 NA 6 (0.0) 0 NA 34 (0.0) 1 (2.9) 1 (100.0) 62 (0.0) 1 (1.6) 1 (100.0)
50≤ COI <100 121 (0.0) 0 NA 55 (0.1) 0 NA 102 (0.1) 0 NA 278 (0.0) 0 NA
COI ≥100 11,099 (2.4) 0 NA 2,784 (2.6) 0 NA 7,395 (4.0) 0 NA 21,278 (2.8) 0 NA
Total 467,206 (100.0) 466 (0.1) 201 (43.1) 108,632 (100.0) 154 (0.1) 93 (60.4) 185,944 (100.0) 362 (0.2) 231 (63.8) 761,782 (100.0) 982 (0.13) 525 (53.5)
COI ≥0.9 12,081 (2.6) 462 (3.8) 199 (43.1) 3,172 (2.9) 154 (4.9) 93 (60.4) 8,201 (4.4) 361 (4.4) 231 (64.0) 23,454 (3.1) 977 (4.2) 523 (53.5)
COI ≥1.0 12,017 (2.6) 444 (3.7) 190 (42.8) 3,143 (2.9) 148 (4.7) 92 (62.2) 8,163 (4.4) 353 (4,3) 230 (65.2) 23,323 (3.1) 945 (4.1) 512 (54.2)
0.9≤ COI <100 982 (0.2) 462 (47.0) 199 (43.1) 388 (0.4) 154 (39.7) 93 (60.4) 806 (0.4) 361 (44.8) 232 (64.3) 2,176 (0.3) 977 (44.9) 524 (53.6)

Abbreviations: COI, cutoff index; No. sample, number of samples with each COI range; sample%, percentage of samples with each COI range; No. NT, number of sample neutralization test performed; NT%, percentage of neutralization test samples among HBsAg test samples; NT Pos, number of samples with positive results on neutralization tests; Pos%, percentage of samples with positive results on neutralization tests; NA, not available; HBsAg, hepatitis B surface antigen.

Lab Med Qual Assur 2024;46:103~108 https://doi.org/10.15263/jlmqa.2024.46.2.103
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