The EQUAL-qual program provided DNA, blood samples, and primers sets to participant laboratories to assess DNA extraction and PCR amplification. There were 213 participating laboratories from 25 European countries and 82% of labs submitted results.
The results showed considerable variability in all phases of the experiment. Questionable results in terms of quality and/or quantity of DNA extracted were found in 27% of labs, low rate of aplification was presented in 3% of labs and 10% of labs not reported rthe expected number of bands of the amplified targets