Research-Based Literacy Practices for Students with Visual Impairments
Kay Alicyn Ferrell, Ph.D.
Loana K. Mason, M.A.
National Center on Low-Incidence Disabilities
No Child Left Behind Act
- Best practices based on scientifically-based research
- Accountability for student proficiency
No Child Left Behind Act, 2001
Scientifically-Based Research
"Research that involves the application of rigorous, systematic, and objective procedures to obtain reliable and valid knowledge relevant to education activities and programs"
No Child Left Behind Act, 2001
Components of Scientifically-Based Research
- Systematic, empirical methods
- Rigorous data analysis
- Measurements or observational methods
- Random assignment or other techniques to eliminate competing explanations
- Sufficient detail and clarity to allow for replication
- Peer-reviewed journal or independent panel of experts
- Appropriate designs and methods for research question
20 U.S.C. 7801, Section 9101(37)
Characteristics of Reliable Research
- Scientific Method
- Replicated
- Generalized
- Meets rigorous standards
- Convergent findings
No Child Left Behind Act, 2001
Accountability
- State standards
- All students reading at or above grade level by the end of 3rd grade
- Adequate yearly progress
- BVI students in CO (without additional disabilities)
- 52% of 5th graders proficient in reading
- 50% of 8th graders proficient in reading
- 39% of 10th graders proficient in reading
No Child Left Behind Act, 2001
National Reading Panel
- Convened to assess the status of research-based knowledge/practices in reading instruction
- Over 25,000 studies reviewed, but only 432 analyzed
- Conclusions about students with disabilities
- Disabled readers have difficulty learning how to spell
- Phonics instruction had a positive and significant effect on disabled readers' reading skills
- Research evaluated on students with disabilities primarily dealt with learning disabilities
- Studies on students with disabilities sometimes included and sometimes excluded
National Reading Panel, 2000
Reading Components
- Alphabetics
- Fluency
- Comprehension
- Teacher Education
- Computer Technology
National Reading Panel, 2000
National Center on Low-Incidence Disabilities
Received Sliver Grant from Colorado Department of Education to improve the literacy outcomes for students who are blind/visually impaired, deaf/hard of hearing, deaf-blind, or who have severe disabilities by conducting a meta-analysis
What do we know?
Meta-Analysis
An analysis of analyses
- A method of synthesizing research on a topic in order to determine the overall effects of the treatment(s)
- Go beyond narratives because they utilize systematic, explicit, quantitative methods
Literature Review
Search Procedures
- Operational definitions
- Literacy - the ability to read and write
- Searching the Literature
- Electronic searches
- ERIC
- PsychINFO
- William S. Gray Database
- Kraus Curriculum Database
- Manual Searches
- JVIB & New Outlook for the Blind
- RE:view & Education of the Visually Handicapped
- Citation Searches
Keyword Searches
| Reading | Writing | Literacy |
| blind | blindness | visual impairment | ||
| partial vision | partially sighted | ||
| deafblind | deaf-blind | deafblind | ||
| vision disorders | eye disorders | ||
| braille | braille instruction | ||
| optical aids | low vision aids | large type | ||
| aural | aural learning | auditory | auditory learning | audio books | audiotape recordings | books on tape | cassette books | ||
Inclusion/Exclusion Criteria
- Published in peer reviewed journals between 1963-2003
- Participants were blind, visually impaired, or deaf-blind
- Participants were children between the ages of 3-21
- Study contained an intervention and comparison group
Filtering Process
- 32 Qualifying
- 7 Not Located
- 97 No Comparison Group or Intervention
- 35 Sighted/Learning Disabled Participants
- 211 Not Age 3-21
- 173 Practitioner
- 97 Not Directly Related to Literacy
- 652 Peer Reviewed
Breakdown of Qualifying Articles
- 16 effect size computed
- 7 single subject designs
- 9 insufficient statistics to compute effect size
- 32 qualifying articles
Analysis
Article Write-Ups
- Research question/hypothesis
- Sample
- Design
- Variables
- Results/conclusions
- Screened by at least two individuals and classified as intervention study
Study Design & Implementation Device (DIAD)
Completed by at least two individuals
- Intervention's relevance to the review
- Outcome measure's relevance to the review
- Clarity of causal inference: Fair comparison
- Randomized designs
- Quasi-experimental designs
- Regression discrimination designs
- Single-factor within-subject designs
- Single subject designs
Valentine & Cooper, 2004
DIAD (continued)
- Clarity of causal inference
- Generality of findings: inclusive sampling
- Generality of findings: effects tested within sub-groups
- Precision of outcome: effect size estimation
- Precision of outcome: statistical reporting
Valentine & Cooper, 2004
Effect Size
"An effect size is the difference between two means (e.g., treatment minus control) divided by the standard deviation of the two conditions. "
Thalheimer & Cook, 2002
Effect Size (continued)
- 1.0 means treatment group scored 1 standard deviation above comparison group
- 0 means treatment group and comparison group scored the same
- -1.0 means the comparison group scored 1 standard deviation above treatment group
- 0.2 is considered a small effect size
- 0.5 is considered a moderate effect size
- 0.8 is considered a large effect size
Correction for Small Sample Sizes
What if Means and Standard Deviations are not Reported?
Use F-statistic
Unreported Statistics (continued)
Or use t-statistic
Preliminary Results
What do we know?
How do we know it?
Aural Comprehension
| Cohen's d | Effect Size | Effect |
| 0.668 | Moderate | Comprehension greater for braille vs. large type readers on delayed recall (Brothers, 1971) |
| 0.664 | Moderate | Comprehension greater on immediate recall (Brothers, 1971) |
| 0.532 | Moderate | Comprehension greater for braille vs. large type readers on immediate recall (Brothers, 1971) |
Preliminary results only; do not quote or cite.
Haptic Memory
| Cohen's d | Effect Size | Effect |
| 0.801 | Large | Delayed recall, after auditory interference, greater than immediate recall (Anater, 1980) |
Preliminary results only; do not quote or cite.
Braille Reading Speed
| Cohen's d | Effect Size | Effect |
| 1.827 | Huge | Reading faster with left hand than right hand (Hermelin & O'Connor, 1971) |
| -1.362 | Very Large | Decrease in reading rate (words/minute) for fiction passages in reduction conditions (Martin & Bassin,1977) |
| 1.238 | Very Large | Decrease in silent reading rate when braille cells are degraded (Millar, 1987) |
Preliminary results only; do not quote or cite.
Braille Reading Speed (continued)
| Cohen's d | Effect Size | Effect |
| 1.061 | Large | Increase in silent reading rate after training in braille code recognition (increase in words/minute) (Umsted, 1972) |
| 0.662 | Moderate | Increase in braille reading speed after paced reading practice with braille tape reader (Flanagan, 1966) |
| -0.640 | Moderate | Decrease in reading rate for science passages in reduction conditions (Martin & Bassin, 1977) |
Preliminary results only; do not quote or cite.
Braille Reading Speed (continued)
| Cohen's d | Effect Size | Effect |
| 0.452 | Small | Increased accuracy in oral reading rate after training in braille code recognition (Umsted, 1972) |
| -0.375 | Small | Increase in reading rate after paced reading with IBM Braille Reading Machine (Kederis, Nolan, & Morris, 1967) |
| -0.347 | Small | Decrease in reading rate for news passages in reduction conditions (Martin & Bassin, 1977) |
Preliminary results only; do not quote or cite.
Braille Reading Comprehension
| Cohen's d | Effect Size | Effect |
| 1.966 | Huge | Decreased comprehension in articulatory suppression condition (Millar, 1988) |
| -0.775 | Moderate | Decreased comprehension scores after training with IBM Braille Reading Machine (Kederis, Nolan, & Morris, 1967) |
| 0.499 | Small | Decrease in comprehension while foot tapping (Millar, 1990) |
Preliminary results only; do not quote or cite.
Braille Reading Comprehension (continued)
| Cohen's d | Effect Size | Effect |
| -0.429 | Small | Decreased comprehension of news passages under reduction condition (Martin & Bassin, 1977) |
| 0.363 | Small | Decreased comprehension scores after paced reading with tachtistomometer (Kederis, Nolan, & Morris, 1967) |
Preliminary results only; do not quote or cite.
Braille Reading Duration
| Cohen's d | Effect Size | Effect |
| -1.084 | Large | Decreased duration when reading news passages under reduction condition (Martin & Bassin, 1977) |
| -0.615 | Moderate | Decreased duration when reading science passages under reduction condition (Martin & Bassin, 1977) |
Preliminary results only; do not quote or cite.
Braille Reading Skills
| Cohen's d | Effect Size | Effect |
| 3.567 | Huge | Greater accuracy in identifying paired cells of standard size (Millar, 1977) |
| -2.449 | Huge | Decreased number of retracings after paced reading practice with braille tape reader (Flanagan, 1966) |
| 2.026 | Huge | Greater accuracy when finger rotated in same orientation to braille cell (Millar, 1987) |
Preliminary results only; do not quote or cite.
Braille Reading Skills (continued)
| Cohen's d | Effect Size | Effect |
| 1.043 | Large | Increased overall tactile and braille recognition scores (Mangold, 1978) |
| 0.539 | Moderate | Decreased errors after training in braille code recognition (Umsted, 1972) |
| -0.522 | Moderate | Decrease in vertical movements after paced reading practice with braille tape reader (Flanagan, 1966) |
Preliminary results only; do not quote or cite.
Braille Reading Skills (continued)
| Cohen's d | Effect Size | Effect |
| 0.458 | Small | Decreased verbal errors after paced reading practice with braille tape reader (Flanagan, 1966) |
| -0.298 | Small | Decreased errors after reading practice with programmed tachtistoscopic device (Flanagan & Joslin, 1969) |
| -0.281 | Small | Decreased retracings after reading practice with programmed tachtistoscopic device (Flanagan & Joslin, 1969) |
Preliminary results only; do not quote or cite.
Braille Reading Skills (continued)
| Cohen's d | Effect Size | Effect |
| -0.252 | Small | Decreased verbal errors after paced practice with braille tape reader (Flanagan, 1966) |
| -0.229 | Small | Decreased skippings after paced practice with braille tape reader (Flanagan, 1966) |
Preliminary results only; do not quote or cite.
Print Reading Comprehension
| Cohen's d | Effect Size | Effect |
| 0.519 | Moderate | Increase in oral comprehension after instruction in use of low vision devices (Corn, Wall, & Bell, 2001) |
Preliminary results only; do not quote or cite.
Print Reading Speed
| Cohen's d | Effect Size | Effect |
| 0.369 | Small | Increased oral reading speed after instruction in use of low vision devices (Corn, Wall, & Bell, 2001) |
Preliminary results only; do not quote or cite.
Amount of Print Reading
| Cohen's d | Effect Size | Effect |
| 0.743 | Moderate | Increase in total number of pages read by 7-9th graders when using low vision devices (Laskey, Efron, & Rowls, 1982) |
| 0.694 | Moderate | Increase in number of school books read by 4th and 5th graders when using low vision device (Laskey, Efron, & Rowls, 1982) |
| 0.674 | Moderate | Increase in total number of books read by 4th and 5th graders when using low vision devices (Laskey, Efron & Rowls, 1982) |
Preliminary results only; do not quote or cite.
Amount of Print Reading (continued)
| Cohen's d | Effect Size | Effect |
| 0.547 | ModerateIncrease in total number of books read by 7-9th graders when using low vision devices (Laskey, Efron, & Rowls, 1982) | |
| 0.397 | Small | Increase in non-school books read by 7-9th graders when using low vision devices (Laskey, Efron, & Rowls, 1982) |
| 0.361 | Small | Increase in non-school books read by 4-5th graders when using low vision devices (Laskey, Efron, & Rowls, 1982) |
Preliminary results only; do not quote or cite.
Amount of Print Reading (continued)
| Cohen's d | Effect Size | Effect |
| 0.335 | Small | Increase in number of school books read by 7-9th graders when using low vision devices (Laskey, Efron, & Rowls, 1982) |
Preliminary results only; do not quote or cite.
16 Qualified Studies, but . . .
- 14 with small to huge effect sizes
- Of these 14, 8 also included analyses with negligible effect sizes
- 2 studies had only negligible effect sizes:
- Gardner (1985)
- Koenig & Ashcroft (1983)
- Multiple experiments in one article could not be used if same sample participated
But Remember . . .
- Still have 7 single subject designs to analyze
- 9 studies did not provide sufficient data to compute an effect size
Levels of Evidence
- Meta-analysis including well-designed randomized controlled studies
- Controlled studies without randomization and quasi-experimental designs
- Well-designed nonexperimental studies (i.e., correlational and case studies)
- Expert committee report, consensus conference, experience of respected professionals
ASHA (2004)
Recommendations for Researchers
Details!!
Population
- Age
- Gender
- Visual Functioning
- Additional Disabilities
- Ethnicity
- Educational Setting
Statistics
- Means
- Standard Deviations
- Effect Sizes
Recommendations (continued)
- Replication studies
- More experimental research
- Meta-analyses of specific interventions
- Research on students who are deafblind
- Research on students with additional disabilities
Limitations
- Possibility that a relevant study was overlooked
- Publication bias since only included articles published in peer reviewed journals
- Generalization not possible due to limited number of studies in any given intervention