The extensive modification and joint re-standardization of the Wechsler Adult Intelligence Scale (WAIS) and Wechsler Memory Scale (WMS) resulted in their publication in the USA in 1997 as the WAIS-III and WMS-III. Larger standardization samples were used than previously, both tests were extensively updated in content and presentation, their age and ability ranges were extended, and a greater range of scoring options was introduced. For the first time the two tests were standardized using the same normative sample and scoring systems were brought into line, making comparisons between them much easier.

Publication of a revised version of the test in USA (1997) yielded an Anglicization of the scale in UK and changes were made in the scale so as to be applicable to the British population. The previous versions of WMS- III i.e. WMS (1945), and WMS – R had been adapted in UK, and had been anglicized to be used on the British population. However, the tests had not been standardized in the UK, and the appropriateness of the tests to the UK population was being questioned. Hence there was a need for the WMS-III test battery to be anglicized to investigate the applicability of the USA norms. Therefore, to utilize to the fullest extent a large body of USA data, the UK project took the form of a validity and comparability study between the American norms and the scores of a representative sample of the UK population. This project was carried out with the intention of providing sufficient information to allow well-informed use of the USA norms in the UK.

Despite the standardization work carried out in the UK for the WMS-III, the utility of the same test battery in India was considered inadequate. Many limitations, such as cultural specificity, test sophistication and educational background of the subjects, are considered as confounding factors for the test results. Therefore, a need was felt for a culture specific comprehensive memory scale, suitable for the Indian population. The WMS-III^IND research project was carried out to develop Indian norms and to establish the reliability and validity of the scale. The WMS-III^IND is considered appropriate for use not only within India but also within the Indian subcontinent, due to cultural similarities among the countries in this geographical area.

The first stage of the India study involved inspection of the WMS – III^UK item pool and its adaptation for the Indian population, where necessary, to ensure that items were appropriate for the Indian population. A thorough item review was undertaken. The India adaptation process was carried out very conservatively in order to minimize any changes in item difficulty. The limited nature of the changes which were necessary reflects the efforts made in the India standardization project to minimize cultural biases and produce an instrument which would require little modification for use in different cultures. The early work included consultation with users of the WMS-III^UK whose comments were taken into account in the final versions of the adaptation of the scale.

The factors i.e., the underlying dimensions, or constructs of the WMS-III^IND were investigated by Exploratory Factor Analysis, using the Principal Component method. The Principal Component method provides a matrix of correlations, which explains the interrelationships among the variables. For the factor analysis, 20 variables were selected in the ratio of 1:10 for the standardization sample of 240 individuals. These 20 test variables constituted the main scores of the subtests.

Four components were extracted from the 20 variables. Factor 1 comprises of Logical Memory test; Factor 2, General Memory, comprises of Word Lists, Visual Reproduction, Letter-Number Sequencing, Spatial Span, Mental Control and Digit Span tests; Factor 3, Associative Learning, includes the tests of Verbal Paired Associates and Family Pictures and Factor 4, Recognition Memory, comprises of the Faces test.

Please contact us for more information, including statistics, related to the validity measures obtained for the WMS-III^IND project.

The WMS–III^IND was developed for assessing learning and memory abilities of individuals in the age range of 16–50 years. The test items, materials, and administration directions were selected for suitability and effectiveness with individuals within this age range. In the case of out-of-age-range testing, the norms may not be representative and additional clinical judgement should be exercised. It should also be borne in mind that the norms for WMS-III^IND could be established up to Percentile Scores. All Index and Scaled Scores are based on the original US and UK data. Additional clinical judgment should be exercised when interpreting the test results using the WMS-III^IND.

The WMS–III^IND is designed to provide relevant information for general clinical and neuropsychological evaluations, as well as for rehabilitation evaluations. Traditionally, the Wechsler scales have been a standard for clinical research. The addition of multiple subtest scores and indexes in the WMS–III^IND will provide those conducting clinical research with multiple, standardized scores, which should further research and further knowledge of memory assessment.