C. Clifford Defee, Brent Williams, Wesley S. Randall, Rodney Thomas, (2010) in their research paper "An inventory of theory in logistics and SCM research", analysed the theoretical categories and presented to explain the type and frequency of theory usage. They concluded that over 180 specific theories were found within the sampled articles. Theories grouped under the competitive and microeconomics categories made up over 40 per cent of the theoretical incidences. This does not imply all articles utilize theory. The research found that theory was explicitly used in approximately 53 per cent of the sampled articles