A multistage adaptive test of fluid intelligence.

Background: Multistage adaptive testing has recently emerged as an alternative to the computerized adaptive test. The current study details a new multistage test to assess fluid intelligence. Method: An item pool of progressive matrices with constructed response format was developed, and divided into six subtests. The subtests were applied to a sample of 724 college students and their psychometric properties were studied (i.e., reliability, dimensionality and validity evidence). The item pool was calibrated under the graded response model, and two multistage structures were developed, based on the automatic test assembly principles. Finally, the test information provided by each structure was compared in order to select the most appropriate one. Results: The item pool showed adequate psychometric properties. From the two compared multistage structures, the simplest structure (i.e., routing test and two modules in the next stages) were more informative across the latent trait continuum and were therefore kept. Discussion: Taken together, the results of the two studies support the application of the FIMT (Fluid Intelligence Multistage Test), a multistage test to assess fluid intelligence accurately and innovatively.