How long to run a reading intervention before changing it
By the IEP Atlas editorial teamLast updated
Short answer
Run a reading intervention long enough to collect 6 to 8 progress monitoring points, usually 6 to 8 weeks with weekly probes, before judging it. Earlier, act if the four most recent points all fall below the goal line. Before changing the program, check attendance, minutes delivered and fidelity. A flat graph from missed sessions is a schedule problem, not an intervention problem.
There is no federal number of weeks. The answer comes from the data: enough points to see a trend, collected while the intervention was really happening. Most teams land on 6 to 8 weeks of weekly probes for a first decision, then smaller adjustments every few weeks after that.
Changing too soon wastes good instruction, because one or two low scores can be noise. Waiting too long wastes months of a student's year. This page shows the decision rules teams use, the checks to make first, and one student's timeline with real dates. For the full cycle, see the reading intervention pillar.
The decision rules most teams use
The National Center on Intensive Intervention describes two common ways to judge progress against a goal line: the four-point rule and trend analysis.[1]
- Four-point rule. After each new probe, look at the four most recent points. If all four fall below the goal line, change the instruction. If all four are above, consider raising the goal. If they are mixed, keep going.
- Trend analysis. Once there are about 6 to 8 points, draw a trend line through them. If it is flatter than the goal line, change the instruction. If it is steeper, consider raising the goal.
The four-point rule can trigger a change as early as week 4. Trend analysis needs more points but is less swayed by a short run of odd days. The four-point rule guide and how many data points you need cover both in detail.
How often you probe sets the clock. Weekly probes give a decision in 6 to 8 weeks. Probes every 2 weeks double that. Tier 2 progress should be checked at least monthly,[3] but for a student whose data you will act on, weekly or every other week is far more useful.
Check these before you change anything
A flat graph has five common causes, and only one of them is the wrong intervention.
| Check | Question | If the answer is no |
|---|---|---|
| Attendance | Was the student present for at least 90% of sessions? | Fix attendance or the schedule first |
| Dosage | Were the planned minutes actually delivered? | Protect the block before changing the program |
| Fidelity | Was the program taught as designed? | Coach the teacher or observe a session |
| Match | Does the program target the skill the diagnostic found? | Change the focus, not just the minutes |
| Measure | Does the probe measure what is being taught? | Add a probe that matches the skill |
Only when all five are yes does the data say the intervention itself is not working for this student.
What to change, from smallest to largest
The National Center on Intensive Intervention's taxonomy of intervention intensity lists the dimensions a team can adjust, including dosage, alignment with the student's needs, attention to transfer and individualization.[2] Start with the smallest change that addresses the likely cause:
- More practice opportunities inside the same lesson (more words read, more turns).
- More time: add a session or 10 minutes per session.
- Smaller group: move from 5 students to 2 or 3.
- Better alignment: change the focus to the skill the diagnostic points to.
- A different program or a more intensive tier, with a fresh diagnostic.
Make one change at a time, write it on the graph with the date, and give it another 4 to 6 points before judging it. Two changes at once leave you guessing which one worked.
Scenario: Ethan's fall
Ethan is a fictional second grader. All numbers are illustrations.
September 15. Baseline on grade 2 passages: 18 words correct per minute (median of 3). Goal line: 48 words correct per minute by January 26, about 18 weeks, or roughly 1.7 words per week. He starts a decoding group of 5, 30 minutes, 4 days a week, with weekly probes.
Weeks 1 to 4 (September 22 to October 13). Scores: 19, 18, 24, 20. The goal-line values for those weeks are about 20, 21, 23 and 25. Three of the four points are below, but week 3 sat just above the line. Under the four-point rule, all four must be below to trigger a change. The team keeps going.
Week 7 (November 3). Scores now read 19, 18, 24, 20, 20, 21, 22. The last four points (20, 20, 21, 22) are all below the goal line, which by then sits between 25 and 30. Time to check, not yet to change programs.
November 4, the checks.
- Attendance: present for 21 of the 22 sessions that were held. Fine.
- Dosage: the group lost 6 sessions to assemblies and testing. Only 22 of 28 planned sessions happened.
- Fidelity: an observation shows the lesson is taught as written.
- Match: the program spends most time on blends; Ethan's diagnostic showed short vowels are still weak.
- Measure: the passage probe is fine, but there is no short-vowel probe.
The change, November 6. Two problems: lost sessions and poor alignment. The team protects the block from pull-outs and moves Ethan to a group of 3 that is working on short vowels. They add a 20-word short-vowel list every 2 weeks. Only the group changes, not the program.
November 10 to December 15. Scores: 24, 27, 26, 30, 32, 34. The short-vowel list rises from 9 to 17 of 20. His trend line is now slightly steeper than the goal line.
January 26, winter benchmark. Ethan reads 46 words correct per minute. Close to the goal and climbing; the team keeps the plan and sets the next goal from his new rate.
If the change had not worked, the team's next step would have been more intensive support with a fresh diagnostic. If Ethan's parents had requested an evaluation at any point, the school would have had to respond, whatever stage the intervention was at.
Rules and options, and where they differ
| Question | Who decides | Varies by state or district? |
|---|---|---|
| How many weeks before a decision | District MTSS plan; usually 6 to 10 weeks | Yes |
| Which decision rule (four-point, trend) | District plan or data team | Yes |
| How often tier 2 is probed | District plan; guidance says at least monthly[3] | Yes |
| How long a student stays in intervention before referral is considered | District plan and state learning disability criteria | Yes[4] |
| Whether intervention can delay an evaluation a parent requests | Federal guidance: it cannot[7] | No |
| When the school must seek consent to evaluate a student not making adequate progress | Federal rule: promptly, after an appropriate period of time[5] | The "appropriate period" is not defined in federal law |
When the student has an IEP
For a student with an IEP, the same rules apply to goal data, and the IEP team must revise the IEP to address a lack of expected progress toward the annual goals.[6] An instructional change inside the same goal and service does not always need a meeting, but a change to the services, minutes or goal does. The guide on what to do when a student is not making progress covers that process. The reading IEP goals library has goal templates in the units these probes use.
Tools
- Graph weekly probes on the reading fluency data sheet.
- Learn probe rules in the oral reading fluency measurement guide.
- Set the probe calendar with the reading intervention progress monitoring schedule.
- Decide between layers with tier 2 vs tier 3 intervention, and regroup with grouping students for reading intervention.
Frequently asked questions
How many weeks should a reading intervention run before you change it?
Usually 6 to 8 weeks with weekly probes, which gives 6 to 8 data points. Act sooner if the four most recent points all fall below the goal line, after checking attendance, minutes delivered and fidelity.
What should I check before changing a reading intervention?
Check attendance, the minutes actually delivered, whether the program was taught as designed, whether it targets the skill the diagnostic found, and whether the probe measures that skill. Fix those problems before switching programs.
Does a student have to fail an intervention before being evaluated?
No. Federal guidance says RTI cannot be used to delay or deny an evaluation of a child suspected of having a disability, and a parent can request an evaluation at any time.
Use it in IEP Atlas
- Reading IEP goals
- Oral reading fluency measurement guide
- Reading fluency data sheet
- Goal line in the IEP glossary
Related guides
- Reading intervention for students with IEPs: assess, group, teach, monitor
- Tier 2 vs Tier 3 reading intervention
- Grouping students for reading intervention
- Reading intervention progress monitoring schedule
- Decision rules: the four-point rule and trend analysis
- Reading intervention games
Sources
- Progress Monitoring: Data & Goal Setting, National Center on Intensive Intervention
- What Is the Taxonomy of Intervention Intensity?, National Center on Intensive Intervention
- Assisting Students Struggling with Reading: Response to Intervention (RtI) and Multi-Tier Intervention in the Primary Grades, What Works Clearinghouse, Institute of Education Sciences
- 34 CFR §300.307: Specific learning disabilities, U.S. Department of Education (IDEA website)
- 34 CFR §300.309: Determining the existence of a specific learning disability, U.S. Department of Education (IDEA website)
- 34 CFR §300.324: Development, review, and revision of IEP, Legal Information Institute, Cornell Law School
- OSEP Memo 11-07: Response to Intervention (RTI) (January 21, 2011), U.S. Department of Education, Office of Special Education Programs
Written and checked by the IEP Atlas editorial team under our editorial policy. This guide describes general practice and federal rules. It is not legal advice; your state may add requirements, and the IEP team makes the decisions for each student.