These states may represent heterogeneity stemming from a variety of factors, such as spatial and other population structures.
Furthermore, an analysis taking into consideration the ethnicity could bring useful information in this field since adiponectin genetic variants may represent heterogeneity among populations [ 39].
For example, previous work by our group suggests that concentrations of tumor necrosis factor-alpha (TNF-α), a major pro-inflammatory cytokine, may represent heterogeneity between euthymic BD patients in association with longitudinal measures of lithium response [ 12].
These thresholds are 0%to40%0% (might not be important), 30% to 60% (may represent moderate heterogeneity), 50%to90%0% (may represent substantial heterogeneity), and 75%to100%0% (considerable heterogeneity) (35).
The Cochrane Collaboration [ 31] provides the following interpretation of I: 0% to 30%, might not be important; 30% to 60%, may represent moderate heterogeneity; 50%to90%0%, may represent substantial heterogeneity; and 75%to100%0%, considerable heterogeneity.
0 to 40%: might not be considered important, 30 to 60%: might represent moderate heterogeneity, 50 to 90%: may represent substantial heterogeneity, and 75 to 100%: considerable heterogeneity [ 21].
Depending on the results of I-squared test; heterogeneity was interpreted depending on the following parameters: 0 to 40%: might not be considered important, 30 to 60%: might represent moderate heterogeneity, 50 to 90%: may represent substantial heterogeneity, and 75 to 100%: considerable heterogeneity [ 21 ].
It ranges from 0%to100%0% and the following rough rule of thumb has been proposed [ 1]: 0% to 40%: might not be important 30%to6060%: may represent moderate heterogeneity 50%to9090%: may represent substantial heterogeneity 75%to10000%: considerable heterogeneity.
In accordance with the Cochrane Handbook, I statistics were interpreted as (0 40%, might not be important; 30 60%, may represent moderate heterogeneity; 50 90% may represent substantial heterogeneity; 75 100%, considerable heterogeneity).
Statistical heterogeneity will also be quantified with the I 2 test, using the following guidelines for the interpretation of the I 2 values: 40 0–40%: might not be important; 30 60%: may represent moderate heterogeneity; 50 90%: may represent substantial heterogeneity and 75 100%: considerable heterogeneity.
The Cochrane Handbook guide to the interpretation of the I statistic will be used: 0 30% might not be important, 30 60% may represent moderate heterogeneity, 50 75% may represent substantial heterogeneity, and 75 100% represents considerable heterogeneity.
