The determinants of obstetricians’ willingness to undertake delivery by vaginal birth after cesarean section in Taiwan

Figures & data

Table 1 Description of variables

Variables	Definitions
WTU index and content
WTU Index	An index ranging from 0 to 1 that indicates the likelihood of a respondent to undertake a VBAC childbirth plan.
Q1 (Willingness)	=1 if the respondent is willing to undertake a planned VBAC when the situation allows it, considering patient safety and hospital conditions; =0 otherwise
Q2 (Actual experience)	=1 if the respondent has experience in undertaking VBAC in the current workplace; =0 otherwise (actual experience)
Q3 (Managerial attitude)	=1 if the managerial attitude of the respondent’s current workplace is supportive towards obstetricians undertaking a planned VBAC; =0 otherwise
Q4 (Past failure)	=1 if the respondent has previous failed VBAC experiences; =0 otherwise
Q5 (Opposition)	=1 if the respondent does not recommend VBAC for average obstetricians; =0 otherwise
Obstetrician background
CS_Table	=1 if the respondent has experience in undertaking CS after a failed vaginal delivery; =0 otherwise
Tenure	Number of years the respondent has been an obstetrician
Risk Tolerance Index	Constructed from 6 questions with a 6-point Likert scale. Thus, the index ranged from 6 to 36 and was then rescaled to a range of 0–1. A higher value indicates a less risk-averse person, and a lower value suggests a more risk-averse person.
Legal	=1 if the respondent has previous experience with a malpractice legal lawsuit; =0 otherwise
Institutional status
Category	=1 if the workplace of the respondent is a clinic; =2 if it is a community hospital; =3 if it is a regional teaching hospital; =4 if it is a medical center
Teach	=1 if the respondent works in a teaching hospital; =0 otherwise
Institutional characteristics
NICU	=1 if the respondent’s workplace has a newborn intensive care unit; =0 otherwise
Pediatrican_24	=1 if there are pediatricians on standby duty 24 hrs a day in the respondent’s workplace; =0 otherwise
Anesth_24	=1 if there are anesthesiologists on standby duty 24 hrs a day in the respondent’s workplace; =0 otherwise
Support	=1 if there are rotating support personnel in the labor and delivery room; =0 otherwise
Facility	=1 if the respondent thinks the supporting personnel in his/her workplace have sufficient professional ability to support VBAC; =0 otherwise
TtoT	The time that it takes to transfer a woman from the labor and delivery room to the operating room

Table 2 Statistical summary by hospital category

	Whole sample	Clinic	Community	Regional	Medical center
	Mean/SD	Mean/SD	Mean/SD	Mean/SD	Mean/SD
Observation number	231	78	23	54	76
Male (%)	69.10	69.62	77.27	67.92	67.11
	(46.31)	(46.28)	(42.89)	(47.12)	(47.30)
Age (years)	40.38	43.57	40.11	40.94	36.43	***
	(7.86)	(6.08)	(7.35)	(7.00)	(8.66)
Tenure (years)	17.66	21.89	17.06	16.47	14.01	***
	(10.96)	(10.65)	(12.01)	(8.55)	(11.19)
Risk tolerance index (0–1)	0.37	0.33	0.35	0.39	0.40	***
	(0.19)	(0.21)	(0.21)	(0.18)	(0.17)
Legal (%)	31.63	36.99	35.00	35.29	22.54
	(46.61)	(48.61)	(48.94)	(48.26)	(42.08)
CS_Table (%)	38.30	36.36	25.00	15.79	65.12	***
	(48.78)	(48.66)	(44.72)	(36.95)	(48.22)
Q1 (% willingness)	86.74	82.05	77.27	88.68	98.68	***
	(31.79)	(38.62)	(42.89)	(31.99)	(11.47)
Q2 (% actual exp.)	71.33	56.96	50.00	73.58	93.51	***
	(44.85)	(49.83)	(51.18)	(44.51)	(24.80)
Q3 (% managerial att.)	71.74	65.38	43.18	69.81	91.55	***
	(38.69)	(43.62)	(41.67)	(38.40)	(20.52)
Q4 (% failure exp.)	59.50	56.58	52.38	65.38	66.23
	(48.77)	(49.89)	(51.18)	(48.04)	(47.60)
Q5 (% opposition)	35.44	58.11	45.45	24.53	21.05	***
	(48.23)	(49.67)	(50.96)	(43.44)	(41.04)
WTU Index (0–1)	0.69	0.57	0.51	0.70	0.84	***
	(0.28)	(0.30)	(0.29)	(0.31)	(0.16)
Teach (%)	47.90	0.00	9.09	64.15	97.40	***
	(50.10)	(0.00)	(29.42)	(48.41)	(16.01)
NICU (%)	54.70	9.59	27.27	76.92	98.68	***
	(49.56)	(29.65)	(45.58)	(42.54)	(11.47)
Pediatrican_24 (%)	72.20	32.88	77.27	86.54	98.68	***
	(44.90)	(47.30)	(42.89)	(34.46)	(11.47)
Anesthesia_24 (%)	75.68	41.10	63.64	94.23	1.00	***
	(43.00)	(49.54)	(49.24)	(23.54)	(0.00)
TtoT (min)	10.25	8.30	12.85	12.23	8.69
	(11.23)	(15.79)	(11.88)	(8.57)	(8.88)
Support (%)	72.85	28.89	76.47	92.68	95.83	***
	(44.62)	(45.84)	(43.72)	(26.37)	(20.19)
Facility (%)	75.57	71.62	54.55	66.67	91.89	***
	(43.07)	(45.39)	(50.96)	(47.61)	(27.48)

Notes: SD are in parentheses. TtoT represents transferring from labor and delivery table to operating table. Other definitions of each variable are in Table 1. ***Denotes difference at 1% significance level across institutional levels.

Table 3 Validity test for WTU index

	Pearson correlation coefficients						Regression
	WTU	Q1 Willing	Q2 Actual experience	Q3 Managerial attitude	Q4 Past failure	Q5 objection	WTU
WTU	1.00
Q1: Willing	0.56*** (0.00)	1.00					0.24*** (17.6)
Q2: Actual experience	0.92*** (0.00)	0.39*** (0.00)	1.00				0.52*** (44.5)
Q3: Managerial attitude	0.61*** (0.00)	0.45*** (0.00)	0.44*** (0.00)	1.00			0.15*** (11.2)
Q4: Past failure	−0.04 (0.55)	0.06 (0.37)	0.18*** (0.01)	0.17*** (0.01)	1.00		−0.09*** (10.7)
Q5: Objection	−0.45*** (0.00)	−0.19*** (0.00)	−0.22*** (0.00)	−0.24*** (0.00)	0.03 (0.68)	1.00	−0.06*** (7.2)
Risk	0.21*** (0.00)	0.19*** (0.00)	0.14*** (0.02)	0.19*** (0.00)	0.04 (0.51)	−0.20*** (0.00)	0.14*** (6.34)
R^2			–				0.99
N			231				231

Notes: ***Denotes difference at 1% significance level across institutional levels. WTU rages from 0 to 1, while all other variables are binary with 0 (no) or 1 (yes) answer. N is observation number.

Table 4 Regression analysis of obstetricians’ willingness to undertake VBAC^a,b,c

	(1)	(2)	(3)	(4)	(5)	(6)	(7)
		Q1	Q1	Q2	Q3
	WTU index	Willing – whole sample	Willing – sample w/actual exp	Actual exp	Managerial attitude	WTU male	Female
Age	−0.21**	−0.50	−0.38	−0.68	−0.92	−0.12	−0.4***
	(−2.23)	(−0.58)	(−0.34)	(−1.07)	(−1.24)	(−0.99)	(−2.62)
Male	0.04	−0.20	−0.76	0.40	−0.23	–	–
	(0.97)	(−0.57)	(−1.44)	(1.54)	(−0.78)
Risk	0.22***	2.04***	1.88**	1.13**	1.34**	0.28***	−0.02
	(2.44)	(2.75)	(2.15)	(1.90)	(2.10)	(2.55)	(−0.09)
TtoT	−0.1***	−0.43***	−0.14	−0.47***	−0.29**	−0.07***	−0.05
	(−2.92)	(−2.51)	(−0.68)	(−3.25)	(−2.03)	(−2.63)	(−1.14)
Support	−0.01	0.22	0.30	0.11	−0.13	−0.02	−0.01
	(−0.22)	(0.71)	(0.81)	(0.46)	(−0.47)	(−0.39)	(−0.13)
NICU	0.14***	0.37	0.09	0.80***	0.58*	0.12**	0.26***
	(2.82)	(0.97)	(0.20)	(2.60)	(1.76)	(2.04)	(2.53)
Facility	0.10**	0.35	0.17	0.55**	0.65***	0.10**	0.17
	(2.43)	(1.12)	(0.46)	(2.20)	(2.54)	(1.97)	(1.74)
Anesth_24	0.09	0.50	0.52	0.29	0.35	0.10	0.00
	(1.60)	(1.23)	(1.14)	(0.95)	(1.05)	(1.55)	(0.02)
CS_table	0.14**	0.78**	0.06	0.51	0.03	0.16**	0.12
	(2.59)	(2.23)	(0.12)	(1.59)	(0.10)	(2.29)	(1.27)
Teach	−0.01	−0.44	−0.04	0.01	−0.02	0.02	−0.13
	(−0.16)	(−1.04)	(−0.09)	(0.02)	(−0.06)	(0.43)	(−1.45)
Constant	1.15***	2.21	2.42	2.08	3.80	0.84	1.87***
	(3.28)	(0.68)	(0.58)	(0.87)	(1.35)	(1.75)	(3.24)
(Pseudo) R^2	0.33	0.23	0.18	0.25	0.21	0.34	0.45
N	231	231	200	231	231	159	72

Notes: ^aColumn (1) uses WTU index as a dependent variable, and linear regression was performed in this model. Columns (2), (3), (4) and (5) are probit models for binary dependent variables from survey questions Q1–Q3. In these columns, pseudo R² values are reported. Age and TtoT are taken as the natural logarithm. Risk ranges from 0 to 1. All other variables take 0 or 1 binary values. ^bt-statistics are in parentheses. ^c1%, 5%, and 10% significance levels are denoted by ***, **, and *, respectively.

Table 5 Regression analysis of obstetricians’ WTU index^a,b,c

	(1)	(2)	(3)	(4)	(5)	(6)	(7)
	Actual past		Experience		Tenure year
	Whole time	Current employment	Ever failure	No failure	<10	10–30	>30
Age	−0.23**	−0.11***	−0.12	−0.24	–	–	–
	(−2.32)	(−2.74)	(−0.99)	(−1.34)
Male	0.00	0.00	0.01	0.01	0.00	0.03	0.13
	(0.08)	(0.10)	(0.11)	(0.16)	(0.04)	(0.57)	(0.76)
Risk	0.19**	0.13***	0.31**	0.05	0.09	0.42***	0.20
	(1.98)	(3.05)	(2.28)	(0.30)	(0.56)	(3.17)	(0.66)
TtoT	−0.05**	0.02	−0.09***	−0.02	−0.07*	−0.04	−0.03
	(−1.98)	(1.43)	(−3.29)	(−0.44)	(−1.70)	(−0.95)	(−0.38)
Support	0.01	−0.01	0.01	−0.02	−0.01	−0.03	0.00
	(0.17)	(−0.75)	(0.28)	(−0.25)	(−0.25)	(−0.52)	(0.03)
NICU	0.11**	0.02	0.15**	0.12	0.21**	0.14**	−0.24
	(2.09)	(0.87)	(2.22)	(1.25)	(2.12)	(2.19)	(−1.05)
Facility	0.10**	0.03*	0.14**	0.06	0.03	0.19***	−0.06
	(2.28)	(1.72)	(2.63)	(0.73)	(0.34)	(3.39)	(−0.40)
Anesth_24	0.09	0.03	0.06	0.13	0.03	0.01	0.18
	(1.60)	(1.18)	(0.75)	(1.29)	(0.32)	(0.16)	(1.21)
CS_table	0.09	−0.01	0.19***	0.00	0.11	0.25***	−0.08
	(1.60)	(−0.50)	(2.89)	(0.04)	(1.20)	(3.28)	(−0.37)
Teach	0.01	0.01	−0.06	0.09	−0.05	0.02	0.37
	(0.22)	(0.72)	(−1.00)	(0.95)	(−0.57)	(0.27)	(1.63)
Constant	1.28***	1.10***	0.82*	1.43	0.65***	0.13	0.45**
	(3.43)	(7.56)	(1.73)	(2.18)	(3.97)	(0.96)	(2.26)
R^2	0.31	0.25	0.31	0.44	0.20	0.45	0.36
N	200	165	138	62	76	112	43

Notes: ^aIn all models, WTU was analyzed as a dependent variable. Age and TtoT are taken as natural logarithms. Other explanatory variables have binary values. Column (1) shows the subgroup analysis for obstetricians with actual VBAC experience anytime in the past. Column (2) shows the subgroup analysis for obstetricians with actual VBAC experience at the current workplace. Column (3) shows the subgroup analysis for obstetricians with failed VBAC experience. Column (4) shows the subgroup analysis for obstetricians without prior VBAC failure. ^bt-statistics are in parentheses. ^c1%, 5%, and 10% significance levels are denoted by ***, **, and *, respectively.