Condition category
Mental and Behavioural Disorders
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Children’s early language and literacy skills are key predictors of later educational outcomes. Children from low socio economic status (SES) backgrounds and immigrant backgrounds have elevated risk for adverse educational outcomes (delays in language and literacy). Research suggests that language and literacy interventions may have positive impact on children’s outcomes. However, the majority of this research has been done in the USA on a relatively small number of children from low-income homes. SPELL is a large study that will test systematic and explicit education in Denmark, under ‘real-life’ circumstances, including all children in the participating day care centers.

Who can participate?
All children of age 3 and above (in practice up to age 6) in the participating day care centers. Centers to be invited will on purpose be selected to over-represent day care centres with a high concentration of children at risk.

What does the study involve?
SPELL is a 20-week intervention which uses storybook reading and provides an explicit scope and sequence of language and literacy education over 40 lessons (2 lessons a week).
Day care centers will be randomly allocated to one of three groups:
- SPELL Basic + Extra professional development group: educators implement the SPELL program and receive special training
- SPELL Basic + Learning activities in the home group: educators implement the SPELL program and parents also implement SPELL activities at home
- Business as usual also called control group: educators do not implement the SPELL program

What are the possible benefits and risks of participating?
All children, in particular those at risk for delays in language, can gain from participating in the study.
There are no risks involved.

Where is the study run from?
Day care centers are located in municipalities in the three main islands of Denmark (Zealand, Jutland, and Funen). We intend to include 128 day care centers, each with on average three classes and 20 children/two day care educators in each class.

When is the study starting and how long is it expected to run for?
January 2013 to June 2014

Who is funding the study?
The Danish Council for Strategic Research (Denmark).

Who is the main contact?
Professor Dorthe Bleses

Trial website

Contact information



Primary contact

Prof Dorthe Bleses


Contact details

Campusvej 55
+45 6550 3346

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

A randomized controlled trial of a large scale systematic and explicit language and literacy intervention in Danish day care centers: The SPELL study


Study hypothesis

Our primary aim is to use a causally interpretable design (randomized controlled trial) to evaluate the impact of the SPELL intervention on children’s language and literacy development, particularly in children at-risk due to low socioeconomic or bilingual immigrant backgrounds, and on day care educators’ process quality. We hypothesize to achieve moderate to large effects on children's language and literacy outcomes. We hypothesize that those children whose day care educators receive extra professional development which emphasizes the use of strategies to differentiate education across the full range of child abilities, will make the greatest language and literacy gains. We hypothesize that children whose caregivers implement a SPELL home companion activities, featuring two weekly adult-child storybook reading lessons with targeted language and literacy activities twice weekly will make significantly increased language and literacy gains.

Ethics approval

The study is registered with the Danish Data Protection Agency. In Denmark, Ethics Committees only review biomedical research so there is no place where trials like SPELL can be reviewed.

Study design

Cluster-randomised randomized trial of a language and literacy intervention.

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type

Quality of life

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Language delay or language impairment in children aged 3-5


SPELL is a 20-week intervention which provides an explicit scope and sequence of language and literacy education over 40 lessons implemented at an intensity of two per week. Each lesson is implemented in a small group format and lasts approximately 30 minutes. The same set of 10 high quality story books will be used repeatedly, i.e. each book will be read four times as the vehicle for instruction. Each lesson involves two components: 1) SPELL lesson plan, which soft-scripts a sequence of step-by-step education featuring a before-, during-, and after-reading activity as well as suggested language that day care educators can use to support children’s learning during each activity, and 2) Learners’ Ladder, which presents specific strategies to differentiate within the lesson on the basis of the individual children’s response to the lesson.
In SPELL Basic + Extra professional development, day care educators will implement all SPELL Basic components and will receive an additional intensive two-day training to increase their substantive knowledge regarding the development and educational needs of children at risk for language and literacy. The educators will receive a language profile based on the pre-test data of each child in their groups, specific training in recognizing and practicing differentiation strategies by watching others and own video recordings of SPELL lessons; and a weekly refresher session in which the two educators working in each classroom conduct small assignments to assist implementation of this knowledge in class.
In SPELL Basic + Learning activities in the home, day care educators will implement all SPELL components and in addition, parents are asked to implement SPELL activities twice a week at home to complement the SPELL intervention that children receive in class. Parents will receive accompanying materials (the same 10 books, 20 lesson plans for each book reading that address the same learning domains and learning targets as in SPELL Basic) and the home activities will be aligned to day care activities.
In Business as usual (Control), day care educators will not receive the SPELL intervention materials or SPELL training. They will continue to provide the type of education that is typical of Danish day care centers.

Intervention type



Not Applicable

Drug names

Primary outcome measure

1. In children, language and literacy measures (vocabulary, narratives, phonological awareness, letter identification). These outcomes are measured pre-post intervention.
2. In educators, an instructional support measure (classroom assessment scoring system). This outcome is measured pre-post intervention.
3. In parents, quality of home learning (only arm with home-aligned activities). This outcome is measured pre-post intervention

Secondary outcome measures

In children, socio-emotional development measure (strengths and difficulties questionnaire). This outcome is measured pre and post intervention.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

We will recruit children in 128 daycare centers.

Participant type


Age group




Target number of participants

The target number of participants is 700 educators and 7680 children from several municipalities in Denmark

Participant exclusion criteria

The only exclusion criterion pertains to children with developmental delays that may be integrated in day care centers

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Campusvej 55

Sponsor information


The Danish Council for Strategic Research (Denmark)

Sponsor details

Ministry of Higher Education and Science
Bredgade 40
København K
+45 3544 6200

Sponsor type




Funder type


Funder name

The Danish Council for Strategic Research (Denmark) (no. 11-115756)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes