Improving the Academic Performance of First-Grade Students With Reading and Math Difficulty
Phase: NA
Conditions: Reading Learning Disability, Math Learning Disability
Sponsor: Vanderbilt University

Improving the Academic Performance of First-Grade 
Students with Reading and Math Difficulty 
 
NCT03991234 
 
Study Protocol and Statistical Analysis Plan 
 
 
10/27/2025 
 
 
 
 
 

 
Improving the Academic Performance of First-
Grade Students with Reading and Math Difficulty 
NCT03991234 
 
Study Protocol 
Summary: The main purpose of this clinical trial is to explore short-term effects of 
coordinated intervention versus the business-as-usual school program on the primary 
endpoints of post-intervention word-reading ﬂuency and arithmetic ﬂuency. The study 
population is students who begin 1st grade with delays in word reading and calculations. 
Students who meet entry criteria are randomly assigned to coordinated intervention across 
reading and math, reading intervention, math intervention, and a business-as-usual 
control group (schools' typical program). The 3 researcher-delivered interventions last 15 
weeks (3 sessions per week; 30 minutes per session). Students in all 4 conditions are 
tested before researcher-delivered intervention begins and after it ends. 
Eligibility: The student attends a participating school in the Metropolitan-Nashville Public 
Schools and is a member of a ﬁrst-grade classroom whose teacher has agreed to let 
his/her students participate. The student must have the available school schedule to 
participate and adequate English proﬁciency to be reliably assessed in English on study 
entry screening measures. The student must score at or below the 25th percentile on the 
study's screening math test, score at or below the 25th percentile on the study's screening 
reading test, and score at or above the 7th percentile on at least one of the study's two 
measures of cognitive performance 
Detailed Description: First-grade students who meet study entry criteria are identiﬁed 
near the start of the school year using a 3-stage screening process. Students who enter the 
study complete the pretest battery. 
Then, students are randomly assigned at the individual level to coordinated intervention, 
reading intervention, math intervention, or a business-as-usual control group (the schools' 
typical classroom instruction with supplemental intervention schools choose to provide). 
Research staff deliver intervention in the coordinated intervention condition, in the reading 
intervention condition, and in the math intervention condition 1:1 for 15 weeks (three 30-
min sessions per week, scheduled in line with teacher input to avoid students missing 

important content). Adherence to the researcher-delivered interventions is monitored via 
audio recordings and live observations. 
The content of each researcher-delivered intervention is aligned with the school district's 
1st-grade foundational reading & math learning standards; relies on explicit instruction; 
and incorporates ﬂuency-building activities word reading and/or arithmetic problems; 
incorporates procedures designed to build engagement and perseverance. Reading 
intervention is designed to build skill in letter-sound associations, decoding, sight words, 
and contextualized reading. Math intervention is designed to build number knowledge, 
counting strategies, and arithmetic skills. Coordinated intervention addresses the same 
instructional objectives as reading intervention & math intervention. 
When researcher-delivered intervention ends, students in all four conditions complete the 
posttest assessment battery. Testers are blind to students' study conditions. Adherence to 
testing protocols is monitored via audio recordings. The primary endpoints are posttest 
word-reading ﬂuency and arithmetic ﬂuency. 
 
Statistical Analysis Plan 
For the analyses, we pooled data across the cohorts. Intra-class correlations (ICCs), 
indicating dependence due to clustering ranged from .010-.133 at the classroom-level 
(level-2) and from .001-.044 at the school-level (level-3). Therefore, for each outcome 
measure, we conducted ﬁt a three-level multilevel model with students (level-1) nested 
within classrooms (level-2), nested within schools (level-3). For each model, we adjusted 
for pre-test performance at level-1 and cohort at level-2, and accounted for missing data 
using full information maximum likelihood estimation. All analyses were conducted in 
Mplus 8.4 (Muthen & Muthen, 1998-2025).