The who, what, why and how of intervention programmes: Comments on the DDAT evaluation

The study by Reynolds, Nicolson and Hambly has highlighted many of the methodological challenges for those conducting practical intervention studies. These have been mentioned by previous commentators and need not, therefore, be rehearsed. I choose to focus here on three key issues where a little further discussion might prove useful, especially for ‘nonspecialists’, including many parents and teachers who are not practised in the interpretation of research in applied cognitive psychology. These are my how, who, what questions: How might the training impact on literacy skills, who does it seem to work for, what is the effect of the training}what is the training doing? The first of these issues concerns what the authors refer to as ‘transfer’}how improvements in some skills brought about through training might produce improvements in other skills that have not been directly trained. It is one thing to give a programme of exercises or activities which enable people to do better on tests that involve the same kind of activity; if I practice balancing on a wobbleboard, I will probably get better at doing tests that involve balance. But how might that improvement affect other skills? Will practising balancing make me a better reader? If it does make me a better reader, how might that happen? Perhaps I have got more confident about taking tests, perhaps I have become more willing to take risks and more prepared to ‘have a go’, perhaps the training activities have taken the place of things that were proving stressful. Perhaps I have become ‘test smart’}better at predicting what is going to happen and better at orienting to the key demands and tuning out the distractions. All of these are possibilities that must be considered before suggesting that the training has brought about a fundamental change in the way that my cerebellum or some other part of my brain is working.