What Works for Children with Literacy Difficulties? - Digital ...

1-year follow-up, July 1979 (Tizard et al., 1982):
Sample sizes. average scores on NFER Reading Test BD and s.d’s:
N Average score (s.d.)
Experimentals 66 99.0 (10.5)
Controls 78 91.6 (11.0)
AI (extra teacher help) 37 96.3 (12.3)
Controls for AI 58 92.9 (12.6)
Statistical significances: Experimentals were significantly better than their controls; the AI
group and their controls did not differ.
3-year follow-up, July 1981 (Hewison, 1988):
Sample sizes. average scores on London Reading Test (national norms) and s.d’s:
N Average score (s.d.)
Experimentals 41 101.0 (11.9)
Controls 69 94.5 (13.5)
AI (extra teacher help) 34 98.9 (14.3)
Controls for AI 56 97.3 (11.3)
Statistical significances: Experimentals were significantly better than their controls; the AI
group and their controls did not differ.
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