Evidence base for educational interventions

This unit summarises the evidence for and against different educational interventions. It explains why interventions need to be planned and evaluated in the context of individual pupils’ needs, and the factors that you should consider when choosing an intervention.

The unit covers the following areas:

  • The strengths and limitations of interventions
  • The importance of understanding the characteristics of autism before making judgements about interventions
  • Key features of effective interventions
  • The reliability of autism intervention studies
  • How to evaluate an intervention
  • The TEACCH programme
  • The SCERTS framework

Research evidence on educational interventions

This mind map highlights some of the prevalent problems that can be experienced in collecting research evidence on educational interventions.


Difficulties with intervention evaluation

  • Small sample sizes

    A small sample size (less than 20 pupils) can limit the scope of data produced in a study and the insight it can provide across variables such as region and social circumstances.

  • Unconfirmed diagnoses and hidden difficulties

    Participating pupils may have unconfirmed diagnoses and hidden difficulties that obscure the effects of an intervention.

  • Lack of objectivity

    The majority of studies are carried out by the same people who developed the intervention, resulting in a lack of objectivity.

  • Same pupils, multiple interventions

    Pupils on the autism spectrum are often involved in multiple interventions, making it difficult to evaluate individual cases.

  • Therapist drift

    ‘Therapist drift’ is when teachers and parents will ‘drift’ into a style that they feel more comfortable with, altering the intervention and its effects.

  • Interventions too short

    Most studies are relatively short-term, often lasting less than a year.

  • Lack of planning

    Intervention studies should have a clear focus from the outset, and can be undermined by a lack of clarity and planning, in terms of the rationale, aims, and what constitutes a successful intervention.


Key steps in evaluating an intervention

  1. Describe rationale
  2. Identify goals
  3. Select sample
  4. Consider data
  5. Decide timescale
  1. The practice of the intervention and the reasons for carrying it out must be clearly set out. Carefully consider who may be best suited to this intervention method.

  2. Identify the goals of the intervention and the key skills you want pupils to develop.

  3. Use stages 1 and 2 to select an appropriate sample of participants.

  4. Think about the type of information you are going to need about participants. Consider how, and by whom, this information might be collected.

  5. Decide how long is needed for the effects of the study to be observed.

Data collection

A great deal of thought must be put into deciding how data will be collected during an intervention, and methods should be tested out before the evaluation phase begins. You can talk to pupils, parents and staff to find out how well they felt the intervention process went.

Common data collection methods

  • Observation
  • Interview
  • Group discussion
  • Analysis of reports
  • Questionnaires

Work systems

The TEACCH programme employs visual work systems to provide pupils with information about:

  • How many items of work they have to do.
  • How long they have to work.
  • When an item of work is finished.
  • What is next (a reward or motivator).

Work systems give children a visual record of progress.

Work systems

SCERTS assessment process

  1. Establish a profile
  2. Select goals
  3. Choose method
  4. Consider support
  5. Monitor progress
  1. Establish a profile of an individual’s developmental strengths and weaknesses.

  2. Determine meaningful educational goals that reflect the pupil’s profile.

  3. Select the most appropriate learning contexts and teaching strategies.

  4. Determine transactional support that may be necessary to achieve a pupil’s goals.

  5. Monitor the pupil’s progress carefully and in detail.

Evaluating interventions

Empirical research is important, but it is not the only method of evaluating an intervention. Carers can use a range of sources to decide whether an intervention is appropriate.

Sources of information

  • Ideas from current theories
  • Case studies
  • Parents'/practitioners' knowledge of a child
  • Knowledge of a family's social and cultural conventions