Table 3.

Limit-of-detection levels for some HPV^a types and cell lines

HPV type or cell line and variables	No. positive/no. tested	Mean CTb	Positive (%)	95% CI (%)
HPV31 (copies/ml)
600	60/60	36.6	100	94.0–100
300	59/61	37.9	96.7	88.7–99.6
150	49/60	38.7	81.7	69.6–90.5
HPV16 (copies/ml)
1,500	60/60	36.5	100	94.0–100
600	60/60	37.7	100	94.0–100
300	55/61	39.1	90.2	79.8–96.3
HPV18 (copies/ml)
1,500	60/60	36.9	100	94.0–100
600	60/60	38.0	100	94.0–100
300	42/61	39.6	68.9	55.7–80.1
SiHa (HPV16) (cells/ml)
200	60/60	36.9	100	94.6–100
100	60/60	38.0	100	94.6–100
50	53/60	39.3	88.3	77.4–95.2
HeLa (HPV18) (cells/ml)
80	60/60	35.7	100	94.0–100
40	60/60	36.8	100	94.0–100
20	56/60	38.2	93.3	83.8–98.1

^aHPV, human papillomavirus.

^bC_T, cycle threshold.