present-day WAIS-IV has contradicted many of these criticisms, by incorporating a single overall score, using multiple timed tasks, focusing on intellective items and other ways. While this scale has been revised (resulting in the present day WAIS-IV), many of the original concepts Wechsler argued for, have become standards in psychological testing, including the point-scale concept and the performance-scale concept. Wechsler–Bellevue Intelligence Scale The Wechsler–Bellevue tests were innovative in the 1930s because they: gathered tasks created for nonclinical purposes for administration as a "clinical test battery", used the point scale concept instead of the age scale, and included a non-verbal performance scale. Point scale concept In the Binet scales (prior to the 1986 version) items were grouped according to age level. Each of these age levels was composed of a group of tasks that could be passed by two-thirds to three-quarters of the individuals in that level. This meant that items were not arranged according to content. Additionally, an individual taking a Binet test would only receive credit if a certain number of the tasks were completed. This meant that falling short just one task required for the credit, resulted in no credit at all (for example, if passing three out of four tasks was required to receive credit, then passing two yielded no credit). The point scale concept significantly changed the way testing was done by assigning credits or points to each item. This had two large effects. First, this allowed items to be grouped according to content. Second, participants were able to receive a set number of points or credits for each item passed. The result was a test that could be made up of different content areas (or subtests) with both an overall score and a score for each content area. In turn, this allowed for an analysis to be made of an individual's ability in a variety of content areas (as opposed to one general score). The Non-Verbal Performance Scale The non-verbal performance scale was also a critical difference from the Binet scale. The earlier Binet scale had been persistently and consistently criticized for its emphasis on language and verbal skills. Wechsler designed an entire scale that allowed the measurement of non-verbal intelligence. This became known as a performance scale. This scale required a subject to actively do something, such as copying symbols or pointing to a missing detail in a picture, rather than just answering questions.