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Self-Correction Ratio Explained
How to calculate the SC ratio on a running record and what it tells you about a reader's self-monitoring.
The self-correction ratio formula
The self-correction ratio compares how many miscues a reader fixed with how many they made in total. Add errors and self-corrections, divide by self-corrections, and write the result as 1:n. A ratio of 1:4 or lower usually shows the reader is self-monitoring.
SC ratio = 1 : ((errors + self-corrections) ÷ self-corrections)
Formula and the 1:4 guideline follow Reading A-Z's running record scoring guide.
Worked examples
| Errors | Self-corrections | Working | SC ratio |
|---|---|---|---|
| 4 | 4 | (4 + 4) ÷ 4 = 2 | 1:2 |
| 9 | 3 | (9 + 3) ÷ 3 = 4 | 1:4 |
| 10 | 2 | (10 + 2) ÷ 2 = 6 | 1:6 |
| 6 | 1 | (6 + 1) ÷ 1 = 7 | 1:7 |
Read 1:2 as “one self-correction for every two miscues.” The smaller the second number, the more often the child is catching their own errors.
How to read the ratio
- 1:1 to 1:4. The child is noticing when reading does not make sense, sound right or look right, and doing something about it.
- 1:5 and wider. Many errors pass without the child noticing. Prompt for monitoring before you prompt for word solving.
- Very few errors. With one or two errors, the ratio is not reliable. Judge self-monitoring from your notes instead.
Look at what the child used to self-correct
The ratio tells you how often a child self-corrects. Your notes tell you how. For each self-correction, ask what made the child notice.
- Meaning. “That did not make sense,” so they went back.
- Structure. “That did not sound right,” as in a sentence that broke English grammar.
- Visual information. “That did not look right,” so they checked the letters.
A child who only self-corrects using the first letter, for example, needs prompts to check meaning too.
Prompts that build self-monitoring
- “Were you right? How do you know?”
- “Does that make sense?”
- “Does that sound right?”
- “Does that look right? Check the whole word.”
- “You stopped there. What did you notice?”
Praise the self-correction itself, not just the right answer. “I liked how you went back and fixed that” teaches the child that noticing is the skill. You can track the ratio over a term alongside accuracy levels.
Frequently asked questions
What is the formula for self-correction ratio?
Add the errors and the self-corrections, then divide by the self-corrections. Write the answer as 1:n. Nine errors and three self-corrections give 9 plus 3, divided by 3, which is 4, so the ratio is 1:4.
What is a good self-correction ratio?
A ratio of 1:4 or lower, such as 1:2 or 1:3, is generally read as a sign that the child is monitoring their reading. A wider ratio, such as 1:7, suggests many errors go unnoticed.
What if the child made no self-corrections?
The ratio cannot be calculated, because you would be dividing by zero. Record it as no self-corrections and look at whether the errors changed the meaning.
Do self-corrections count as errors?
No. A self-correction is recorded separately and does not lower the accuracy score.
Why does a high-accuracy reader have few self-corrections?
If a child makes very few errors, there is little to correct. With only one or two errors, the ratio says very little, so focus on comprehension instead.
More guides
- How to Calculate WCPM Step-by-step scoring for a timed fluency read, with error rules and grade-level norms.
- Running Record Accuracy Levels What independent, instructional and frustration levels mean, plus an error-rate conversion chart.
- Flesch-Kincaid Grade Level Explained Where the formula comes from, how to calculate it by hand, and what it cannot tell you.
- Average Reading Speed by Grade and Age Oral reading fluency norms for Grades 1 to 6 and adult reading speeds, in one place.