Ladders to Literacy shows mixed effects on comprehension, with no statistically significant vocabulary effects in any study despite an average improvement index of +9¶

Claim · All claims
Evidence · 1 study · quant-synthesis r1 · q3
Currency · newest study 2007 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? Three studies found no statistically significant effect of Ladders to Literacy on the Peabody Picture Vocabulary Test; the WWC rated comprehension effects mixed (average improvement index +9, range +1 to +17). → What Works Clearinghouse 2007

Evidence¶

What Works Clearinghouse 2007¶

What Works Clearinghouse, U.S. Department of Education. (2007). Ladders to Literacy for Kindergarten Students. WWC Intervention Report. https://ies.ed.gov/ncee/wwc/InterventionReport/259

q3 · i? · quant-synthesis · r1

WWC synthesis of three studies reporting the vocabulary construct (PPVT). The report states the authors "did not find a statistically significant effect of Ladders to Literacy on the Peabody Picture Vocabulary Test for any study"; the domain average effect size was 0.23, all non-significant, yielding a mixed rating.

"The studies' authors did not find a statistically significant effect of Ladders to Literacy on the Peabody Picture Vocabulary Test for any study."

Discussion¶

Related Claims¶

• Ladders to Literacy shows potentially positive effects on fluency based on a single non-significant finding with an effect size of 0.72 and an improvement index of +26 — related
• Ladders to Literacy shows potentially positive effects on alphabetics, with an average improvement index of +25 percentile points and a domain average effect size of 0.69 — related