Abstract: The present invention relates to a method for the quantitative analysis of complex nucleic acids (NA), i.e. their fragmentation/degradation and amplificability as a marker of biomolecular quality and integrity of a biosample. Said method comprises the steps of subjecting said NA to a multiplex polymerase chain reaction using primers to generate different-size amplicons (referred to as indicator PCR). For simplicity, a duplex PCR using one primer pair for the generation of a longer PCR product and a second primer pair for the generation of a shorter PCR product is being described as the most simple variant of this test. Following the duplex PCR amplification, the ratio between the yield of the longer PCR product and the yield of the shorter PCR product generated during duplex PCR is determined using a read-out that allows relative quantification between the two (e.g. Pyrosequencing).