Deep cohesion is defined as the amount of connecting words which are helpful in clarifying relations between events, ideas, and information. This characteristic has been identified as an important source of variation in text difficulty.

Existing literature suggests that passages with ambiguous sentences with fewer connectives and more coherence breaks are harder to process and comprehend.

Deep cohesion is often represented by a percentile score, with a higher percentile score indicating more deep cohesion within the passage.