PSSUQ, and Product A receives a score of 2.0 versus Product B's score of 4.0. Given a significant comparison, you could say that Product A had more satisfying usability characteristics than Product B (an ordinal claim), but you could not say that Product A was twice as satisfying as B (a ratio claim).
In conclusion, psychometrically qualified, standardized questionnaires can be valuable additions to practitioners' repertoire of usability evaluation techniques.
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