# What is ICC1?

## What is ICC1?

ICC1 is sensitive to differences in means between raters and is a measure of absolute agreement. ICC2 and ICC3 remove mean differences between judges, but are sensitive to interactions of raters by judges. The difference between ICC2 and ICC3 is whether raters are seen as fixed or random effects.

How is ICC1 calculated?

Very generally speaking, the ICC is calculated as a ratio ICC = (variance of interest) / (total variance) = (variance of interest) / (variance of interest + unwanted variance).

What does low ICC mean?

A high Intraclass Correlation Coefficient (ICC) close to 1 indicates high similarity between values from the same group. A low ICC close to zero means that values from the same group are not similar.

### What is a good ICC value?

ICC Interpretation Under such conditions, we suggest that ICC values less than 0.5 are indicative of poor reliability, values between 0.5 and 0.75 indicate moderate reliability, values between 0.75 and 0.9 indicate good reliability, and values greater than 0.90 indicate excellent reliability.

What is the meaning of intra class?

Within a class
intraclass (not comparable) Within a class.

What is an acceptable intraclass correlation coefficient?

The ICC is a value between 0 and 1, where values below 0.5 indicate poor reliability, between 0.5 and 0.75 moderate reliability, between 0.75 and 0.9 good reliability, and any value above 0.9 indicates excellent reliability [14].

#### What does ICC value mean?

What is intra-class variance?

The variation between multiple observations of an individual (intra-class variance) and the variation between subjects (inter-class variance) define the performance of a biometric system. If the intra-class variance of a biometric trait is low, then the trait is said to demonstrate permanence and repeatability.

What is the difference between interclass and intraclass correlations?

Interclass correlation shows the association among the groups and intra-class correlation shows the association within a group. “Interclass” means among the groups. “Intra class” means within group.

## What does P value mean in ICC?

The p-value for correlation (e.g. Pearson’s r) means how significant is the difference between the obtained Pearson’s r and the number 0 (no correlation). There is a p-value associated with the ICC (intraclass correlation coefficient), too.

What is inter and intra-class variability?

What is the difference between icc1 and icc2?

ICC1 is sensitive to differences in means between raters and is a measure of absolute agreement. ICC2 and ICC3 remove mean differences between judges, but are sensitive to interactions of raters by judges.

### What is a one-way ANOVA?

A one-way ANOVA (“analysis of variance”) compares the means of three or more independent groups to determine if there is a statistically significant difference between the corresponding population means. This tutorial explains the following: The motivation for performing a one-way ANOVA.

What is icc1 (1 rating case)?

(The 1 rating case is equivalent to the average intercorrelation, the k rating case to the Spearman Brown adjusted reliability.) ICC1 is sensitive to differences in means between raters and is a measure of absolute agreement.

What is the dependent variable in a one way ANOVA?

A one-way ANOVA (analysis of variance) has one categorical independent variable (also known as a factor) and a normally distributed continuous (i.e., interval or ratio level) dependent variable. The independent variable divides cases into two or more mutually exclusive levels, categories, or groups.