Why should I help?  

If your child is between the ages of 12-16, we are seeking their involvement in an important study that will help us to understand more about how young people spend their free time. This will help us to identify which activities affect young people’s health and wellbeing.  

Will my child’s answers to these questionnaires be kept private?  

All data will be kept confidential. No personal information (name or identification number) will be recorded in this research and no information about individuals will be given to the schools that participate. All data will be processed anonymously. The results of this study might be presented online or in a scientific journal, but the data is not traceable to an individual.

What does participation involve?  

Children will be asked to fill out an online questionnaire every evening for a week in which they will answer questions about how they spent their leisure time during that day. This will take around 15 minutes to complete. Before the children start, we will ask them once a series of questions about other aspects of their lives such as their friendships, mood, and bullying. This will take about 30 minutes to complete.  

Your child’s participation in this survey is voluntary. If you agree to them participating in this study, you or your child can indicate at any time that you wish to withdraw, without having to give an explanation.  

How can I help?  

If your child’s school has been invited to participate in the research, a letter with a consent form will have been given to you by your child’s teacher, or you can download it here from the website. Depending on the age of you child, we may also need your consent for your child to take part in this study. Please refer to the consent form for more information.    

What if I have more questions?

If you need more information about the study, you could send an email to this address: This email address is being protected from spambots. You need JavaScript enabled to view it..      


Project lead: Prof. Carolien Rieffe This email address is being protected from spambots. You need JavaScript enabled to view it.  

Kick off! The 5-year NWO project officially started

May 13th, 2019

meeting ASDinclusive 10May2019

On Friday May 10th, the kick-off meeting of the NWO project "Breaking the cycle: an inclusive school environment outside the classroom for adolescents with ASD" took place in Leiden, marking the start of this 5-year project. Partners from collaborating universities, professional organizations for autism, and patient associations came together to celebrate the start of this multidisciplinary collaboration and to get ready for the next upcoming years with interesting presentations and lively discussions.



BOLD Talks: Possibilities and implications of sensor data

April 10th, 2019

FOE group 2019 crop names

How can sensor technologies add values to current research? On April 9th, the monthly BOLD Talks was held in our lab on the topic of "Possibilities and implications of sensor data". Daniel Messinger (University of Miami) and Ed Baines (UCL) talked about their work within the framework of BOLD Cities. Adva, Lisa, and Ozge also presented the use of sensor data in their research. During the plenary discussion, the potentials and pitfalls of applying different sensor technologies as well as the possible directions for handling missing data and priviacy were explored. Read more about the talk here.  


World Autism Awareness Day

April 2nd, 2019


The 2nd of April is the internationally recognized World Autism Awareness Day designated by the United Nations, aiming to increase and develop world knowledge of people with Autism Spectrum Disorder (ASD). For this special day, Carolien wrote a blog on autism and bullying to emphasize the importance of diversity and inclusion. You can read the blog here.


BOLD Cities continues for another 5 years

April 2nd, 2019

BOLD Cities

Great news! BOLD Cities received a new LDE (Leiden University, TU Delft, Erasmus University Rotterdam) funding for another 5 years.

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Bachelor project on children with Developmental Language Disorder

February 28th, 2019

NSDSK feb2019

Carolien and Özge are coordinating a bachelor project on social-emotional functioning in children with Developmental Language Disorder (DLD) in the Spring semester 2019.

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Adva's talk on play in children with disabilities

February 25th, 2019 

Adva HebrewUniv Dec2018

On December 26th 2018, Adva participated in a research seminar at the Center for Disability Studies in the Hebrew University of Jerusalem. In her lecture "Play and Toys for All", Adva talked about barriers for play and playfulness in children with disabilities, with a special focus on children with a hearing loss, and referred to the emotional, social and methodological aspects of play.

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Who are we?

FOE group 2019 crop

Our team is located at the department of Developmental Psychology of Leiden University in the Netherlands. We work in close collaboration with the Dutch Foundation for the Deaf and Hard of Hearing Child (NSDSK), the ENT department of the Leiden University Medical Centre (LUMC), the Centre for Autism, the Leiden Institute of Advanced Computer Science (LIACS), TU Delft, and University of Twente. Our group is dedicated to examining the emotional development of children and adolescents of all walks of life. We have a strong focus on the functionality of emotions, and its impact on children's social development. Besides typically developing children and adolescents, we are interested in the development of those who are deaf or hard-of-hearing, with autism spectrum disorders, or with specific language impairments.

On this site we regularly post news items about new publications, events, and so on. You can also read more about our ongoing projects, read about and download questionnaires we have developed,
see an overview of our publications per topic, or read about opportunities for students to join our team.