SDF tests are generally classified into two groups: direct and indirect. In direct tests, the extent of sperm DNA damage is measured using probes and dyes. However, indirect tests assess the susceptibility of DNA to denaturation which occurs more commonly in fragmented DNA. The most commonly used methods to measure SDF are:
- Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)
- Sperm chromatin structure assay (SCSA)
- Sperm chromatin dispersion (SCD) test.