The top section indicates which factors improved the stuttering rate-IPC score relationship. All factors that appear in either language or either age group are listed in the top row and age groups in the left column. Cells where the number is included indicate whether the analysis indicates that factor is important for each language and age group. The bottom section indicates the frequency of occurrence of the difficult attribute of each factor as percentage occurrence out of all words for corresponding age groups in Spanish and English and the signed difference (diff.) in frequency of usage.