The screening test, given to five- and six-year-olds, does not assess the full range of phonics knowledge that the national curriculum calls on these pupils to have, according to Jonathan Solity, honorary research fellow at University College London, and Cat Darnell, psychology researcher at the University of Birmingham.

As a result, the academics suggest that children’s time would be better spent reading books and building their vocabulary, rather than studying some of the more obscure sound combinations occurring in the English language.

The academics conducted a detailed analysis of the words that pupils were asked to read in the phonics tests, and of the test mark scheme. This showed that children were able to pass the assessment with only basic phonics knowledge - rather than the full understanding of the phonics curriculum that the curriculum calls for.

For example, pupils were not tested on knowledge of the long “e” sound made by the letter E in words such as “she”. Nor were they tested on the “ou” sound made in the word “you”. But the curriculum specifies that children should know these sounds.

Slow brown cow

They also found that, while the test was presented as a measure of pupils’ ability to sound out written letters and create words, in fact, pupils needed vocabulary knowledge to work out how to pronounce 40 per cent of the words. This meant that the test measured vocabulary, as well as phonics.

For example, the word “brown” featured in the 2014 test. But the letter combination “ow” can be pronounced differently, depending on the word: “cow”, compared with “slow”. So it was only by having pre-existing knowledge of the word ‘brown’ that pupils were able to pass the test.

Speaking at the annual British Educational Research Association conference tomorrow, the academics will call on the phonics curriculum to include only the small number of common sound and letter combinations occurring in English. Children should then move on quickly to reading real books and building up the vocabulary necessary for decoding less phonetically predictable words, they will say.

“This is not an anti-phonics argument,” Dr Solity said, in advance of his presentation. “It is absolutely clear that children need to be taught phonics.”

But, he added, disadvantaged children would benefit from more time devoted to building their vocabularies, rather than learning obscure sound combinations, as they tend to be exposed to fewer words at home than other children.

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