OHI ADHD Eligibility Criteria: Using Rating Scale Scores for IEP and 504 Plans

You've got the rating scale results in hand — elevated T-scores on the Conners 4, a clinically significant BASC-3 profile, maybe a BRIEF-2 flagging executive dysfunction across the board. Now you need to connect those numbers to the actual legal criteria the school uses to determine whether your child qualifies for an IEP or 504 plan. Here's how the two eligibility pathways work and where rating scale data fits into each one.

IEP Eligibility Under Other Health Impairment

ADHD is named as a health condition that can fall under the IDEA category of Other Health Impairment (OHI); it does not automatically qualify a student for an IEP. The federal regulation — 34 CFR §300.8(c)(9) — defines OHI as "limited strength, vitality, or alertness, including a heightened alertness to environmental stimuli, that results in limited alertness with respect to the educational environment." Three elements must be present:

A health condition. ADHD is explicitly named in the OHI definition. A medical diagnosis is relevant information, but it does not by itself establish OHI eligibility. The school's own evaluation addresses the educational criteria; school teams do not confer a formal medical diagnosis.

Limited alertness in the educational environment. Rating scale scores can provide evidence about attention and executive-function concerns. A Conners 4 Inattention content scale T-score of 65 or higher is Elevated or Very Elevated relative to same-age peers; it does not by itself establish the OHI criterion. BRIEF-2 elevations on the Cognitive Regulation Index (Working Memory, Plan/Organize, Task-Monitor) can help describe executive-function concerns in daily settings.

Adverse effect on educational performance. This is the element schools most often dispute. "Educational performance" under IDEA is not limited to grades. It encompasses academic achievement, functional performance, behavior, social interaction, communication, and work completion. Elevated externalizing scores on the BASC-3 (Hyperactivity, Aggression, Conduct Problems) document behavioral interference. Depressed adaptive scale scores (Adaptability, Social Skills, Functional Communication — T-scores at or below 40) show functional deficits that grades alone don't capture.

All three elements must be met, and the child must need specially designed instruction — not just accommodations — to benefit from education.

504 Plan Eligibility

Section 504 of the Rehabilitation Act uses a different, broader standard. A student qualifies when they have a physical or mental impairment that substantially limits one or more major life activities. ADHD is a qualifying impairment. The major life activities most relevant to ADHD include concentrating, thinking, reading, learning, and communicating.

The 504 threshold is generally considered lower than IDEA's. There's no requirement to prove a need for specially designed instruction — only that the impairment substantially limits a major life activity and that accommodations are needed to provide equal access.

Rating scale scores can provide evidence for the substantial-limitation analysis. A Conners 4 Inattention T-score of 70 is Very Elevated and corresponds to about the 98th percentile in its normative sample; it does not by itself establish a substantial limitation. Scores in the 60–69 range are Slightly Elevated (60–64) or Elevated (65–69) on the Conners 4, and At-Risk on BASC-3 clinical scales; the team considers them with other evidence of functional impact.

Which Scores Map to Which Criteria

Different rating scales address different elements of the eligibility framework:

For documenting limited alertness / inattention: Conners 4 Inattention content scale, BASC-3 Attention Problems clinical scale, Vanderbilt Inattention symptom count (items 1–9, counting responses rated "Often" or "Very Often"), and the ADHD-RS-5 Inattention subscale.

For documenting hyperactivity/impulsivity: Conners 4 Hyperactivity/Impulsivity content scale, BASC-3 Hyperactivity clinical scale, Vanderbilt Hyperactivity-Impulsivity symptom count (items 10–18).

For documenting executive dysfunction: BRIEF-2 Global Executive Composite, Behavioral Regulation Index, Emotion Regulation Index, and Cognitive Regulation Index. These scores are particularly powerful because they measure real-world functional deficits — the gap between what a child knows and what they can consistently do in daily settings.

For documenting broader educational impact: BASC-3 composite indexes (Externalizing Problems, Internalizing Problems, Behavioral Symptoms Index) and adaptive scales. Low adaptive scores are often overlooked but they directly address functional performance — a child with a Social Skills T-score of 35 and a Functional Communication score of 38 has measurable deficits that affect educational participation even if they pass every test.

What to Do When the Team Disagrees on Eligibility

If the school team acknowledges the elevated scores but disputes eligibility, ask them to document their reasoning in writing — specifically which element they believe is not met and what evidence they're relying on. Under IDEA's procedural safeguards, you're entitled to Prior Written Notice explaining the decision.

Common disputes and how rating scale data addresses them:

"Grades are passing, so there's no adverse effect." Respond with the BASC-3 adaptive scale scores, BRIEF-2 functional indexes, and any data on homework duration, work completion rates, or behavioral referrals that grades don't reflect.

"The teacher's ratings are average." Cross-informant disagreement is clinically expected — the research reports average parent-teacher correlations ranging from r = 0.25 to 0.33. Request that the team analyze why the ratings differ rather than defaulting to the lower score. The ADHD Rating Scale Decoder walks through how to present rater discrepancy data at an eligibility meeting.

"ADHD is diagnosed but doesn't affect school." This conflates medical diagnosis with educational eligibility. The two are related but use different standards. The school's job is to determine whether the student's ADHD-related functional profile — as documented by the rating scales, observations, and academic data — meets the eligibility criteria. A medical diagnosis alone doesn't guarantee eligibility, but elevated clinical scores across multiple instruments and informants make a strong case that the condition is affecting the educational environment.