. 2024 Mar 31;27(1):38–46. doi: 10.3831/KPI.2024.27.1.38

Table 5.

Historical control data

Historical control values of structural aberrations

Group	S9 mix	Trt-rec time (hr)	N	Structural aberration cells excluding gap (%) (Mean ± SD)	Range (%)		95% control limit^c) (structural aberration cells/300 cells)

					MIN	MAX
Negative	–	6-18	46	0.304 ± 0.343	0	1.01^*	0	< 3
	+	6-18	46	0.304 ± 0.384	0	1.09^*	0	< 3
	–	24-0	44	0.280 ± 0.387	0	1.002^*	0	< 3
Positive	–	6-18^a)	39	21.97 ± 6.264	8.60^*	35.34^*
	+	6-18^b)	39	22.51 ± 5.418	11.03^*	33.99^*
	–	24-0^a)	37	31.80 ± 9.077	13.26^*	50.35^*
Historical control values of numerical aberrations

Group	S9 mix	Trt-rec time (hr)	N	Numerical aberration cells excluding gap (%) (Mean ± SD)	Range (%)		95% control limit^c) (numerical aberration cells/300 cells)

					MIN	MAX
Negative	–	6-18	46	0.203 ± 0.285	0	0.95^*	0	< 2
	+	6-18	46	0.145 ± 0.250	0	0.85^*	0	< 2
	–	24-0	44	0.227 ± 0.247	0	1.01^*	0	< 2

N, total number of chromosome aberration tests; Negative control, water for injection, dimethyl sulfoxide, acetone, etc.; SD, standard deviation; Trt-Rec time, treatment-recovery times.

^a)Mitomycin C (0.1 µg/mL).

^b)Benzo[a]pyrene (20 µg/mL).

^c)Poisson-based 95% control limits of the historical negative control data.

These historical control values were obtained from data pooled from May 6, 2015 to December 17, 2021.

*Range was calculated using the control limit of X derived from X-R-Rs value.