Butterfly Phonics showed positive but non-statistically-significant effects on secondary outcome measures of single word reading (g = 0.38) and non-word reading (g = 0.23)¶
Claim · All claims
Evidence · 1 study · causalr2·q3
Currency · newest study 2015 · not yet checked against its sources · not reviewed by a person
Subclaims¶
Reading the evidence codes
q is the design tier, i the impact, n the sample, and the kind with its r
the rigour judged within that kind: what each code means.
This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.
q3 i? There was no significant effect of the intervention on SWRT scores (effect size 0.38, 95% CI -0.14, 0.90) or PhAB non-word reading scores (effect size 0.23, 95% CI -0.03, 0.49), though both effects were positive. → Christine Merrell 2015
Evidence¶
Christine Merrell 2015¶
Christine Merrell, Adetayo Kasim. (2015). Butterfly Phonics: Evaluation Report and Executive Summary. Education Endowment Foundation. https://eric.ed.gov/?id=ED581118
q3 · i? · causal · r2
Intention-to-treat multilevel analysis of the two secondary outcome measures in the same randomised controlled trial (SWRT N=170 intervention, 167 control; PhAB same). The evaluators note it "might have been expected" that a phonics programme would show greater improvement on these measures.
"There was no significant effect of the intervention on the SWRT scores with an effect size of 0.38 (-0.14, 0.90) or on the PhAB scores with an effect size of 0.23 (-0.03, 0.49). While the effects were positive in favour of the intervention group, they did not reach statistical significance."
Discussion¶
Learner Variables¶
- Decoding — outcome: instruction changes it
Related Claims¶
- For pupils entitled to free school meals, Butterfly Phonics showed no statistically significant effects on any outcome (NGRT g = 0.16, SWRT g = 0.42, PhAB g = 0.18) — related
- Butterfly Phonics improved reading comprehension of struggling Year 7 readers more than business-as-usual, with an effect size of 0.43 equivalent to five months' progress, but the effect was below the trial's minimum detectable effect size — related
- Remedial reading programs show effects around 0.49 for struggling readers and 0.54 for more severe difficulties — a broader claim this one bears on
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