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Effectiveness
Findings
The WWC review of interventions for Literacy Express addresses student outcomes in six domains: oral language, print knowledge, phonological processing, early reading and writing, cognition, and math. The studies included in this report cover five domains: oral language, print knowledge, phonological processing, cognition, and math. The findings below present the authors’ estimates and WWC-calculated estimates of the size and the statistical significance of the effects of Literacy Express on preschool children.9
Oral language. Farver, Lonigan, and Eppe (2009) analyzed the effectiveness of Literacy Express on oral language using the Preschool Comprehensive Test of Phonological and Print Processing (Pre-CTOPPP) Receptive Vocabulary and Definitional Vocabulary subtests. The analyses showed, and the WWC confirmed, a statistically significant positive effect of 0.57 across the two measures (0.55 for receptive vocabulary and 0.60 for definitional vocabulary) when children in the Literacy Express group were compared to children in the control group. According to WWC criteria, this study shows a potentially positive effect on oral language.
Lonigan et al. (2005) analyzed the effectiveness of Literacy Express on oral language using the Preschool Language Scales–IV (PLS-IV) Expressive Communication subtest. The authors found, and the WWC confirmed, a statistically significant and substantively important positive effect of 0.30 when children in the Literacy Express group were compared to children in the control group. According to WWC criteria, this study shows a potentially positive effect on oral language.
The PCER Consortium (2008) analyzed the effectiveness of Literacy Express on oral language using the Peabody Picture Vocabulary Test III (PPVT-III) and the Test of Language Development–Primary III (TOLD-P:3) Grammatic Understanding subtest. The analyses showed, and the WWC confirmed, that differences between Literacy Express and the control group curriculum are not statistically significant or substantively important on either of these measures. According to WWC criteria, this study shows no discernible effects on oral language.
Print knowledge. Farver, Lonigan, and Eppe (2009) analyzed the effectiveness of Literacy Express on print knowledge using the Pre-CTOPPP Print Knowledge subtest. Their analyses showed, and the WWC confirmed, a statistically significant positive effect of 0.64 when comparing the Literacy Express group and the control group. According to WWC criteria, this study shows a potentially positive effect on print knowledge.
Lonigan et al. (2005) analyzed the effectiveness of Literacy Express on print knowledge using the Pre-CTOPPP Print Knowledge subtest. Their analyses showed, and the WWC confirmed, a statistically significant and substantively important positive effect of 0.32 when Literacy Express was compared to the control group curriculum. According to WWC criteria, this study shows a potentially positive effect on print knowledge.
The PCER Consortium (2008) analyzed the effectiveness of Literacy Express on print knowledge using the Test of Early Reading Ability–III (TERA-3), the Woodcock-Johnson III (WJ-III) Letter-Word Identification subtest, and the WJ-III Spelling subtest. The authors report, and the WWC confirms, that differences between Literacy Express and the control group curriculum are not statistically significant on any of these measures, although there is a substantively important effect of 0.30 on the WJ-III Letter-Word Identification subtest. According to WWC criteria, this study shows no discernible effects on print knowledge.
Phonological processing. Farver, Lonigan, and Eppe (2009) analyzed the effect of Literacy Express on phonological processing using the Pre-CTOPPP Blending and Elision subtests. Their results showed, and the WWC confirmed, a statistically significant and substantively important positive effect of 0.54 across the two measures (0.51 for Elision and 0.56 for Blending). According to WWC criteria, this study shows a potentially positive effect on phonological processing.
Lonigan et al. (2005) analyzed the effectiveness of Literacy Express on phonological processing using the Pre-CTOPPP Blending and Elision subtests. Their analyses showed, and the WWC confirmed, a statistically significant and substantively important positive effect of 0.26 across the two measures. This result was due primarily to a statistically significant and substantively important positive effect of 0.38 on the Elision subtest (the effect on the Blending subtest was neither statistically significant nor substantively important). According to WWC criteria, this study shows a potentially positive effect on phonological processing.
The PCER Consortium (2008) analyzed the effectiveness of Literacy Express on phonological processing using the Pre-CTOPPP Elision subtest. The authors report, and the WWC confirms, that the difference between the Literacy Express group and the control group is not statistically significant or substantively important on this measure. According to WWC criteria, this study shows no discernible effects on phonological processing.
Cognition. Lonigan et al. (2005) analyzed the effectiveness of Literacy Express on cognition using three subtests from the Pre-CTOPPP—Non-Word Repetition, Word Span, and Rapid Object Naming. The authors report, and the WWC confirms, that the differences between the Literacy Express group and the control group were not statistically significant or substantively important for any of these three measures. According to WWC criteria, this study shows no discernible effects on cognition.
Math. The PCER Consortium (2008) analyzed the effectiveness of Literacy Express on math using the WJ-III Applied Problems subtest, the Child Math Assessment–Abbreviated (CMA-A), and the Shape Composition task. The authors report, and the WWC confirms, that differences between the Literacy Express group and the control group are not statistically significant or substantively important on any of these measures. According to WWC criteria, this study shows no discernible effects on math.
Rating of effectiveness
The WWC rates the effects of an intervention in a given outcome domain as positive, potentially positive, mixed, no discernible effects, potentially negative, or negative. The rating of effectiveness takes into account four factors: the quality of the research design, the statistical significance of the findings, the size of the difference between participants in the intervention and the comparison conditions, and the consistency in findings across studies (see the WWC Procedures and Standards Handbook, Appendix E).
9 The level of statistical significance was reported by the study authors or, when necessary, calculated by the WWC to correct for clustering within classrooms or schools and for multiple comparisons. For the formulas the WWC used to calculate the statistical significance, see WWC Procedures and Standards Handbook, Appendix C for clustering and WWC Procedures and Standards Handbook, Appendix D for multiple comparisons. For the Literacy Express studies summarized here, no correction for clustering was needed. In the cases of Farver, Lonigan, and Eppe (2009) and Lonigan et al. (2005), a correction for multiple comparisons was needed, so the significance levels may differ from those reported in the original studies.