Table 2. Duration of labour from one level of cervical dilatation to the next by parity and analysis method.

Parity	Parity = 0			Parity = 1			Parity = 2+
Study	Current study	Current study	Zhang et al. [14]	Current study	Current study	Zhang et al. [14]	Current study	Current study	†Zhang et al. [14]
N	2,166	2,166	25,624	1,488	1,488	16,755	1,952	1,952	16,219
Cervical dilatation	Survival analysis†	Markov model	Survival analysis‡	Survival analysis†	Markov model	Survival analysis‡	Survival analysis†	Markov model	Survival analysis‡
3–4 cm	2.82 (0.60, 13.33)	1.83 (0.08, 8.17)	1.8 (8.1)	2.42 (0.41; 14.18)	1.92 (0.08, 8.33)	NA	2.35 (0.31; 17.85)	2.17 (0.08, 9.75)	NA
4–5 cm	1.72 (0.38, 7.83)	1.58 (0.08, 7.08)	1.3 (6.4)	1.37 (0.25; 7.65)	1.42 (0.08, 6.42)	1.4 (7.3)	1.18 (0.17; 8.05)	1.50 (0.08, 6.5)	1.4 (7.0)
5–6 cm	1.19 (0.23, 6.17)	0.83 (0.00, 3.83)	0.8 (3.2)	0.79 (0.13; 4.95)	0.83 (0.00, 3.58)	0.8 (3.4)	0.79 (0.10; 6.24)	0.75 (0.00, 3.33)	0.8 (3.4)
6–7 cm	0.66 (0.09, 4.92)	0.92 (0.00, 4.25)	0.6 (2.2)	0.33 (0.03; 3.67)	0.75 (0.00, 3.50)	0.5 (1.9)	0.31 (0.03; 3.29)	0.83 (0.00, 3.58)	0.4 (1.2)
7–8 cm	0.25 (0.02, 3.10)	0.58 (0.00, 2.50)	0.5 (1.6)	0.09 (0.00; 2.69)	0.42 (0.00, 1.83)	0.4 (1.3)	0.17 (0.01; 2.44)	0.33 (0.00, 1.50)	0.3 (0.9)
8–10 cm	0.87 (0.18, 4.19)	0.75 (0.00, 3.33)	0.5 (1.4)*; 0.5 (1.8)§	0.64 (0.11; 3.56)	0.67 (0.00, 2.92)	0.3 (1.0)*; 0.3 (0.9)§	0.68 (0.12; 3.77)	0.50 (0.00, 2.50)	0.3 (0.8)*; 0.3 (1.6)§

Current study data reported as median hours (5th, 95th percentiles).

Zhang et al. data reported as median hours (95th percentile).

† Survival analysis with complete and interval-censored values

‡ Survival analysis with interval-censored regression

* 8–9 cm.

§ 9–10 cm.