The scoring process
Your raw score is determined by the number of questions you answer correctly. Questions you answer incorrectly or for which you mark no answer or more than one answer are counted as incorrect. Nothing is subtracted from a score if you answer a question incorrectly.
Your raw score is then converted to a scaled score through a process known as equating. The equating process accounts for minor variations in difficulty among the different test editions. Thus, a given scaled score reflects approximately the same level of ability regardless of the edition of the test that was taken; the same number of correct responses on different test forms will not necessarily result in the same scaled score.