The paper presents a methodology known as the Modified Structural Change/Transformation Index (MSCI) that enables comparisons of the extent of structural transformation/change across countries and regions without considering the historical context of each case's structural transformation. This is significant because developed countries initiated their structural transformation much earlier than emerging and developing countries. The methodology compares the average contributions of economic sectors to GDP between 1970-1975 and 2017-2022 to evaluate structural transformation in countries and regions around the world. The proposed methodology (MSCI) has demonstrated that its findings closely reflect the developmental performance of the countries and regions being assessed based on their average GDP per capita, compared to the results obtained through the traditional Structural Change Index (SCI) for measuring structural transformation.   Two goodness-of-fit tests were employed to ensure the reliability of the statistical analysis results. The paper confirms that the proposed methodology requires further research to refine it. Variables such as economic complexity, human capital, and institutional quality could be considered to enhance measurement accuracy.

Key words: Structural change, structural transformation, methodology, Development