Results from the 2003 follow-up survey suggest that larger cumulative transfers to the household significantly improved outcomes in many aspects of child physical, cognitive, and language development. Specifically, a doubling of the cumulative cash transfers was associated with a 0.20 standard deviation increase in height-for-age Z score, a 0.10 standard deviation decrease in stunting, a 1.15 standard deviation increase in endurance, a 0.18 standard deviation increase on language development test scores, and a 0.12 and 0.13 standard deviation increase in long- and short-term memory, respectively .
The positive effects seen in the short-run survey were also observed in the longer-term. In addition, the 2007 survey showed that the cumulative amount received during the program was also significantly associated with a reduced number of maternal-reported behavioral problems in children 8-10 years old.
The importance of the cash transfer is confirmed when the data is analyzed using a different technique (Manley et al. 2012). The results suggest that the improvements in child development seen under Oportunidades were more linked to the transfers themselves than to other portions of the program, such as the condition that families had to attend certain health and nutrition classes.
The cash component of CCT programs could improve growth, health, and development outcomes for children living in extreme poverty via two pathways. First, the additional income could give parents greater purchasing power. They could use the additional cash to purchase more or higher quality food or medicines, or books and other learning materials to promote learning. The second pathway would be by improving the psychological wellbeing of family members and thereby improving the care and support provided to the children in the household. Due to the limitations of the data collected, however, researchers are not able to comment on the speciﬁc pathways by which cash transfers would have affected outcomes.