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Parental Beliefs, Investments, and Child Development : Evidence from a Large-Scale Experiment of Chile's “Nadie es Perfecto”
Initial registration date
March 11, 2019
March 11, 2019 11:25 PM EDT
Other Primary Investigator(s)
Catholic University of Chile
University College of London, Georgetown University
The World Bank
Additional Trial Information
This study experimentally evaluates a large-scale and low-cost parenting program targeting poor families in Chile. Households in 162 public health centers were randomly assigned to three groups: a control group, a second group that was offered eight weekly group parenting sessions, and a third group that was offered the same eight group sessions plus two sessions of guided interactions between parents and children focused on responsive play and dialogic reading. Three years after the end of the intervention, the receptive vocabulary and the socio-emotional development of children of families participating in either of the treatment arms improved (by 0.43 and 0.54 standard deviation, respectively) relative to children of nonparticipating families. There were no statistically detectable impacts on other types of skills. The treatments also led to improvements in home environments and parenting behaviors of comparable magnitudes, which far outlasted the short duration of the intervention. A simple mediation analysis suggests that up to 13 percent of treatment impacts on language, and up to 36 percent of impacts on child socio-emotional development, can be attributed to changes in the home environment, as well as in nurturing and discipline parenting behaviors.
Bedregal, Paula et al. 2019. "Parental Beliefs, Investments, and Child Development : Evidence from a Large-Scale Experiment of Chile's “Nadie es Perfecto”." AEA RCT Registry. March 11.
NEP is a parenting intervention operating in the context of a broader early childhood policy platform called Chile Crece Contigo (ChCC). The intervention was adapted from the Nobody’s Perfect program in Canada, a long running group parenting intervention implemented within the public health system in Canada. NEP relies on a semi-structured curriculum that promotes knowledge about child development, parental self-care, positive parenting skills in caregivers, and the use of non-violent disciplinary strategies, helping caregivers to foster a nurturing home environment.
NEP targets parents with children aged 0 to 5 who are enrolled in the public health system. Parents are offered participation in the program during the regular health check-ups. The intervention can be applied to all parents who are interested in improving their parental skills, but it is more directly targeted to caregivers who are particularly vulnerable, such as adolescents, single parents, geographically or socially isolated households. Parents in these groups, and other parents which are in need of this type of intervention, can be identified by the health care provider (doctor or nurse) with whom they interact frequently. Households at very high risk (children with severe child developmental delays or disabilities, or high-risk parents with psychiatric problems or intra-household violence) are not considered eligible for NEP and are instead referred to services with more intensive engagements at local level.
The standard program (which we call NEP-Basic, or NEP-B) includes 6 to 8 weekly group sessions with 6-12 caregivers, facilitated by a trained moderator, and based on a curriculum that promotes positive parenting skills to improve cognitive stimulation, to manage child behavior with positive disciplinary strategies, and to improve their parental self-esteem. Each session lasts approximately two hours. An intensive version (NEP-Intensive, or NEP-I) was developed as part of the study as an additional evaluation arm. It adds to NEP-B two practical sessions with children in order to give caregivers the opportunity to interact with their child in a monitored environment and thereby receive more personalized feedback on their practices.
Intervention Start Date
Intervention End Date
Primary Outcomes (end points)
Child development: Language development, Executive Functions, Socio-emotional development, Adaptive Behavior, Cognitive Development
Primary Outcomes (explanation)
Language: At baseline we measured both receptive and expressive language for children from 0 to 71 months using the Spanish version of the Preschool Language Scale (PLS-4). However, because a large proportion of children at endline were older than 71 months and could not be administered the PLSIV, in the endline survey we applied the “Test de Vocabulario en Imágenes” (TEVI-R), a direct assessment for receptive vocabulary that has been adapted from the Peabody PPVT and normed for the Chilean context and was administered to children 36 months of age and older.
Executive function: We applied both at baseline and endline the Dimensional Change Card Sort (DCCS) task (Zelazo 2006), which is appropriate for longitudinal uses starting from age 2 ½ until adulthood. At endline, we also administered a Leiter-R scale to measure the capacity to sustain attention. Socio-Emotional Development: We use two meastures to capture the range of behavioral problems (maladaptive behavior) as well as the positive socio-emotional development (adaptive behavior) as reported by the primary caregiver. We administered the Achenbach Child Behavior Checklist which captures internalizing and externalizing behavioral problems for children aged 1 ½ years and older. In order to measure positive dimensions of how the child establish interpersonal relationships, we used the Battelle Developmental Inventory Screening Test (BDIST II) Personal-Social Scale.
Secondary Outcomes (end points)
Parent well being, parenting practices and home environment:
Secondary Outcomes (explanation)
These are middle-term and short-term intermediate indicators and will include
Physical care of children
Parenting strategies and discipline
Time investments and Expenditures
Perception of social support and self-efficacy
Knowledge of child development and attitudes Expectations on the effect of better practices and investments
Attitudes and beliefs towards child-rearing
We also gather control variables such as
- Demographics, Education, Incomes, Labor status
- Family health, mother health history, children health history
- Facilitators education and experience
- Caregiver depression
The impact evaluation was designed as a randomized control trial in which 175 health clinics, stratified by type of health center, and rural/urban location were randomly assigned to receive the standard basic program NEP-Basic, the more intensive program NEP-Intensive, or no program at all (in the control arm). Within each clinic, a sample of 18 families was randomly drawn from a potential wait-list of
participants formed by facilitators (which usually contains between 45 and 60 potential participants per center). Potentially eligible families were identified during regular health visits to the center and added to the wait-list just prior to the administration of the baseline survey. The 18 families selected to be part of the study were then randomly assigned to three groups: 1/3 was invited to participate in NEP-B, 1/3 was invited to participate in NEP-I, and the remaining 1/3 of families was assigned to the control group. The control group remained on a waiting list up until the endline survey was conducted, at which point they became eligible to participate in NEP. Families in the control group receive no NEP benefits, but they continued to receive their usual health care at the health center, which included non-structured talks with the parents and regular control visits to children. Treatment families were free to accept or not the invitation to participate in NEP.
There were two measurements: a baseline survey before the intervention (June-September 2011) and a follow-up survey 2 years after the end of the interventions, which took place between October 2011 and April 2012. The target population of clinics included basic family health care, rural health clinics, urban health clinics and health establishments with minimal service complexity: this corresponded to about 600 clinics in Chile, covering 342 municipalities. The order by which families were offered the program is determined by the staff in the health center, in conjunction with the program facilitator. The presumption was that the program was offered to those individuals needing it the most, providing they qualify for it.
Experimental Design Details
Randomization done in office by a computer
Was the treatment clustered?
Sample size: planned number of clusters
We controlled for health center fixed effects since treatment assignment was not clustered at the health center level
Sample size: planned number of observations
3150 parents with child aged 0-6 across 175 health centers
Sample size (or number of clusters) by treatment arms
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Our goal is to detect an impact of the program of at least 0.25 SD on different indicators of child development. Since the take up of the program is predicted to be of about 50%, we design our sample to detect a difference of 0.25*0.5=0.125 SD in child development measures between treatment and control parents.
INSTITUTIONAL REVIEW BOARDS (IRBs)
Comité de Etica Servicio de Salud Metropolitano Sur Oriente
IRB Approval Date
IRB Approval Number
Post Trial Information
Is the intervention completed?
Intervention Completion Date
April 01, 2012, 12:00 AM +00:00
Is data collection complete?
Data Collection Completion Date
October 01, 2014, 12:00 AM +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
162 health centers
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
Baseline: 2,916 households; 3598 children
Follow-up: 2,545 households; 2895 children
Final Sample Size (or Number of Clusters) by Treatment Arms
Baseline: Households: 972 in each arm; Children: 1214 in control, 1193 NEP basic, 1191 NEP intensive
Follow-up: Households: 818 control, 869 NEP basic, 857 NEP intensive; Children: 947 control, 987 NEP basic, 961 NEP intensive
Reports, Papers & Other Materials
Parental Beliefs, Investments, and Child Development : Evidence from a Large-Scale Experiment (English)
This paper experimentally evaluates a large-scale and low-cost parenting program targeting poor families in Chile. Households in 162 public health centers were randomly assigned to three groups: a control group, a second group that was offered eight weekly group parenting sessions, and a third group that was offered the same eight group sessions plus two sessions of guided interactions between parents and children focused on responsive play and dialogic reading. Three years after the end of the intervention, the receptive vocabulary and the socio-emotional development of children of families participating in either of the treatment arms improved (by 0.43 and 0.54 standard deviation, respectively) relative to children of nonparticipating families. There were no statistically detectable impacts on other types of skills. The treatments also led to improvements in home environments and parenting behaviors of comparable magnitudes, which far outlasted the short duration of the intervention. A simple mediation analysis suggests that up to 13 percent of treatment impacts on language, and up to 36 percent of impacts on child socio-emotional development, can be attributed to changes in the home environment, as well as in nurturing and discipline parenting behaviors
Amaro Da Costa Luz Carneiro, Pedro Manuel; Galasso, Emanuela; Lopez Garcia, Italo Xavier; Bedregal, Paula; Cordero, Miguel. 2019. Parental Beliefs, Investments, and Child Development : Evidence from a Large-Scale Experiment (English). Policy Research working paper; no. WPS 8743; Impact Evaluation series. Washington, D.C. : World Bank Group. http://documents.worldbank.org/curated/en/191061550167761091/Parental-Beliefs-Investments-and-Child-Development-Evidence-from-a-Large-Scale-Experiment
REPORTS & OTHER MATERIALS