Technical analysis of the Slosson Written Expression Test

The Slosson Written Expression Test was designed to assess students ages 8-17 years at risk for difficulties in written expression. Scores from three independent samples were used to evaluate the test's reliability and validity for measuring students' written expression. Test-retest reliability of the SWET subscales ranged from .80 to .94 (n = 151), and .95 for the Written Expression Total Standard Scores. The median alternate-form reliability for students' Written Expression Total Standard Scores was .81 across the three forms. Scores on the Slosson test yielded concurrent validity coefficients (n = 143) of .60 with scores from the Woodcock-Johnson: Tests of Achievement-Third Edition Broad Written Language Domain and .49 with scores on the Test of Written Language-Third Edition Spontaneous Writing Quotient. Exploratory factor analytic procedures suggested the Slosson test is comprised of two dimensions, Writing Mechanics and Writing Maturity (47.1% and 20.1% variance accounted for, respectively). In general, the Slosson Written Expression Test presents with sufficient technical characteristics to be considered a useful written expression screening test.