The elementary school students were taught a technique for lifting an empty crate from the floor. The lifting performance of each student was rated on an 5-point scale on three occasions: before instruction on lifting (Pretest); two days after instruction (Post 1); and 6-7 weeks after instruction (Post 2). Students were expected to lift the crate keeping a straight back, flexing at the hips and knees, keeping the crate within 15 cm of the body and within the base of support, and without twisting. A student's score was determined by the number of components observed during the lift. Therefore, scores ranged from 0 to 5. Is lifting skill affected by training and is this skill maintained with time after training?

Define problem and state the test or procedure that will be used.

State null and alternative hypotheses (if hypotheses will be tested).

State any statistical assumptions made in performing the analysis. Where possible, assumptions should be verified using approaches outlined in the modules.

State probability level.

Calculate test statistic(s).

Compare calculated test statistic or the calculated p-value with the appropriate critical value.

Accept or reject the null hypothesis (if an hypothesis is tested).

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