Effect of at-birth cash transfers and payment design on child hospital presentations and maltreatment: a quasi-experimental study in South Australia

Background. Cash transfers around birth may improve child health by reducing financial stress and helping families meet urgent household and infant needs. However, causal evidence remains limited on whether payment design affects health impacts, whether unconditional payments influence child safety, and whether benefits extend to older siblings. We examined the effects of an unconditional cash transfer at birth on child health and safety, and whether changing the transfer from a lump sum to instalments altered these effects. Methods. We used linked administrative data for all births in South Australia to evaluate two reforms to Australia’s Baby Bonus program: the 2004 introduction of a lump-sum payment of A$3000 and the 2009 change from a lump-sum payment of A$5000 to 13 fortnightly instalments. We estimated difference-in-discontinuities models comparing outcome discontinuities at each reform date with discontinuities at the same date one year earlier. Primary outcomes were any hospital presentation or admission and any Child Protection Services notification for the focal infant in the first six months after birth. We also examined older sibling outcomes, later follow-up windows, diagnosis-specific hospital outcomes, and maltreatment subtypes. Findings. The 2004 lump-sum payment reduced infant hospital presentations and admissions by 9·8 percentage points (95% CI 7·3 to 12·2), from a pre-reform rate of 22·1%. Reductions were concentrated in respiratory and digestive conditions. Older siblings also had fewer hospital presentations and admissions. The 2009 change to instalments increased infant hospital presentations and admissions by 2·8 percentage points (95% CI 0·1 to 5·5), from a pre-reform rate of 18·4%. Neither reform was associated with detectable changes in Child Protection Services notifications. Interpretation. At-birth cash transfers can improve infant and sibling health without increasing maltreatment risk, but payment design shapes effectiveness: a lump sum produced larger health benefits than the same amount delivered as instalments.