However it was still somewhat laborious and, as it was competing
against real-time PCR, it did not come into widespread use.
Search of Medline and Google Scholar using the term “digital PCR”
showed that the publication rate remained low, at several publications
per year, until 2007. However from that year on there has
been a rapid and exponential increase in the number of publications
referring to digital PCR. At first these publications were predominantly
in engineering and microfluidics journals but during the last
few years there has been an increasing number of publications in
biological and medical journals. This rapid rise in publication rate is
obviously due to the development of new instrumentation which
makes digital PCR a relatively simple and practical method.