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Hi there, I have built a three-level linear model, with Body Mass Index as the dependent variable. In my three-level model, state is at the third level, geographical areas are in the second level and individuals form the lowest level. My ICC for the second-level is high, about 0.96
Is it common to have such high ICC for second level? Please help.

Dear Sherry08,

If you have found a neighbouhood level ICC of 0.96 for BMI, then I suggest something has gone wrong in your calculation. I would expect something more like 0.05! The ICC is the correlation between two randomly selected individuals' BMI from the same neighbourhood and so we would never expect this to be high.

Best wishes

George