A. Model structure
A decision model was developed in the form of a decision tree to compare
the short-term outcomes for women who received PG as an inpatient with
those who received a balloon catheter as an outpatient. A health
services perspective was chosen for the evaluation, from hospital
admission until discharge home of mother and baby. Women moved through
mutually exclusive model pathways, according to transition probabilities
associated with each model arm. The model distinguished the two
comparators (balloon group, PG group) for nulliparous vs parous women
and their probabilities of mode of birth (unassisted vaginal,
instrumental or caesarean section (CS)) and baby requiring nursery
admission vs postnatal ward care. The model structure is illustrated in
the Supplementary material (Figures S1 & S2).