Table 4.
Highest sample size required for three- or one-region approach for cardiac volume protocol performed on 320-row scanner, as a function of anticipated effective dose, precision, and desired confidence level. Sample sizes displayed are for confidence level of 95%, with sample sizes for 90% confidence level in parentheses.
| Precision | Anticipated effective dose (mSv) |
||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (q [%]) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| 2 | 8803(7273) | 2201(1819) | 979(809) | 551(455) | 353(291) | 245(203) | 180(149) | 138(114) | 109(90) | 89(73) | 73(61) | 62(51) | 53(44) | 45(38) | 40(33) |
| 5 | 498(274) | 125(69) | 56(31) | 32(18) | 20(11) | 14(8) | 11(6) | 8(5) | 7(4) | 5(3) | 5(3) | 4(2) | 3(2) | 3(2) | 3(2) |
| 10 | 76(51) | 19(13) | 9(6) | 5(4) | 4(3) | 3(2) | 2(2) | 2(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) |
| 15 | 32(22) | 8(6) | 4(3) | 2(2) | 2(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) |
| 20 | 18(12) | 5(3) | 2(2) | 2(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) |
| 50 | 3(2) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) | 1(1) |