Table 2.

Estimated relative and absolute potencies (IU/mg) of pairs of tuberculin batches with 95% CI's in six guinea pig trials.

Trial	Batch pair	N	Rel. pot. (95% CI)	Potency (95% CI)
T1	RS, BIS	48	1.230 (0.757–2.025)	39,975 (24,603–65,813)*
	A, BIS	48	1.233 (0.828–1.853)	40,073 (26,910–62,223)*
	A, RS	48	1.095 (0.739–1.627)	37,997 (25,643–56,457)**
T2	RS, BIS	48	Non-parallel	–
	A, BIS	48	Significant curvature	–
	A, RS	48	Non-parallel	–
T3	RS, BIS	45	Non-parallel	–
	A, BIS	45	0.782 (0.444–1.338)	25,415 (14,430–43,485)*
	A, RS	46	1.081 (0.760–1.542)	35,133 (24,700–50,115)**
T4	RS, BIS	41	1.132 (0.678–1.893)	39,280 (23,527–65,687)*
	C, BIS	43	1.103 (0.710–1.689)	35,848 (23,075–54,893)*
	C, RS	44	0.957 (0.639–1.417)	33,208 (22,173–49,170)**
T5	RS, BIS	39	0.954 (0.585–1.565)	31,005 (19,013–50,863)*
	D, BIS	42	1.181 (0.794–1.756)	38,383 (25,805–57,070)*
	D, RS	41	1.189 (0.766–1.827)	41,258 (26,580–63,397)**
T6	RS, BIS	41	1.131 (0.745–1.761)	36,785 (24,213–57,233)*
	B, BIS	42	0.975 (0.656–1.465)	31,688 (21,320–47,613)*
	B, RS	39	0.852 (0.559–1.285)	29,564 (19,397–44,590)**
T1, T4, T5, T6	RS, BIS	169	1.115 (0.871–1.432)	36,238 (28,308–46,540)*

^*Relative potencies multiplied by 32,500 (potency assigned to BIS).

^**Relative potencies multiplied by 34,700 (potency assigned to RS when calibrated against bis in cattle).