Replication is the key to the support of any worthwhile theory.  Replication involves the process of repeating a study using the same methods, different subjects, and different experimenters.  It can also involve applying the theory to new situations in an attempt to determine the generalizability to different age groups, locations, races, or cultures.  For example, our study of non-traditional students may be completed using students from another college or from another state.  It may be changed slightly to add additional variables such as age, sex, or race to determine if these variables play any role in our results.

Replication, therefore, is important for a number of reasons, including (1) assurance that results are valid and reliable; (2) determination of generalizability or the role of extraneous variables; (3) application of results to real world situations; and (4) inspiration of new research combining previous findings from related studies.