The strong-inference protocol: not just for grant proposals.

The strong-inference protocol puts into action the important concepts in Platt's often-assigned, classic paper on the strong-inference method (10). Yet, perhaps because students are frequently performing experiments with known outcomes, the protocols they write as undergraduates are usually little more than step-by-step instructions for performing the experiment. The strong-inference protocol, however, includes an explicit statement of possible experimental outcomes and the interpretation that would follow from each. This approach encourages thorough planning, enhances the efficiency of experimental designs, and increases the power of statistical analysis by explicitly stating a priori predictions as well as the statistical methods that will be used to test them. A sample protocol for an experiment investigating temperature-metabolism relations in chicken embryos is provided to illustrate the important components of the strong-inference protocol and to encourage instructors to incorporate this powerful research tool into undergraduate laboratory courses.