No.	Question	Answer
0	Call response	(1) Mother agreed to continue the call (moved to question 1) (2) Babysitter (father, grandparents) agreed to continue the call (moved to question 1) (3) Mother refuse to continue the call (stop the call) (4) Mother is busy (stop the call) (5) Phone number is wrong or not available (stop the call) (7) Baby died (stop the call)
1	How old is your youngest child?	(Note the child’s age in months)
1a	Is your child a boy or a girl?	(1) Boy (2) Girl (9) Others (twins, etc.)
2	Is s/he breastfed?	(1) Yes (move to question 2a) (2) No (move to question 3)
2a	Apart from breastfeeding your child, do you let your child eat or drink anything else?	(1) Exclusive breastmilk (from the biological mother or others) (2) Breastmilk and formula milk (3) Breastmilk and water (9) Breastmilk and other drinks/foods
3	Did you deliver him/her vaginally or via cesarean?	(1) Vaginally (2) Via cesarean
3a	Is your baby pre-term?	(1) <37 weeks (<259 days) (2) ≥37 weeks (≥259 days)
4	Was s/he placed on your chest/abdomen for skin-to-skin contact immediately after birth?	(1) Yes (move to question 5a) (2) No (move to question 5b) (8) No answer (9) Don’t know/don’t remember
5a	How long was s/he in skin-to-skin contact with you?	(1) Less than 90 min (2) More than 90 min (9) Don’t know/don’t remember
5b	How long after birth was your child returned to stay with you?	(1) Immediately or less than one hour (2) From one to six hours (3) More than six hours (9) Don’t know/don’t remember
6	Was your child breastfed within 90 min after birth?	(1) Yes (0) No (8) No answer (9) Don’t know/don’t remember
7	Was your child given water or formula milk during the hospital stay?	(1) Yes (0) No (8) No answer (9) Don’t know/don’t remember
8	Did you receive breastfeeding counseling from doctors and nurses during your hospital stay?	(1) Yes (0) No (8) No answer (9) Don’t know/don’t remember
9	Did doctors and nurses in the hospital counsel you to use formula milk for babies aged under 24 months?	(1) Yes (move to question 9a) (0) No (8) No answer (9) Don’t know/don’t remember
9a	Why were you counseled to use formula milk by doctors/nurses?	(1) Having little breastmilk/no breastmilk (2) Cesarean childbirth (3) The mother is sick, thus not able to breastfeed her baby (4) The baby is sick or born preterm, thus not able to breastfeed (5) The mother wants to feed her baby with formula milk (7) Other (please specify) (8) No answer (9) Don’t know/don’t remember
10	Did you see any forms of advertising/marketing of formula milk for babies aged under 24 months, feeding bottles and artificial pacifiers in the hospital?	(1) Posters or advertisements of infant formula for babies aged under 24 months (2) Formula company staff marketing formula milk for children under 24 months at the hospital (3) Formula milk products for children under 24 months being displayed for sales or introduced by health staff (4) Persons asking for your phone number and calling you to introduce breastmilk substitutes after birth, feeding bottles, or artificial pacifiers (5) Advertisements of formula milk for pregnant women and postpartum mothers (6) Feeding bottles and artificial pacifiers being advertised and displayed for sale (9) Other types of advertisements/marketing about formula milk for babies aged less than 24 months (describe) (0) No abovementioned forms seen
11	Did you have a birth companion of choice at the childbirth ward?	(1) Yes (0) No
12	What is your ethnicity?	(1) Kinh (2) Tay (3) Thai (4) Hoa (5) Khmer … (56) Other (specify in question 12a)
12a	Please specify your ethnicity?
13	Do you have any recommendations for the hospital to better support breastfeeding?	(1) Yes (note down the comments) (0) No