article_snippet: In total, more than 200,000 participants in IQ tests were studied.
article_snippet: This tasks participants with looking for patterns in an array of shapes - and is thought to be a good measure of intelligence.
article_snippet: In total, more than 200,000 participants from 48 countries over 64 years were studied in the research.
article_snippet: RPM is a valid and reliable measure of general IQ, Dr Wongupparaj told MailOnline. '
article_snippet: Also, it is cultural-free test so that it has been widely used for nearly 80 years.'
article_snippet: RPM is seen as an accurate way of measuring intelligence, and 'it is cultural-free test so that has been widely used for nearly 80 years,' Dr Dr Wongupparaj told MailOnline .
article_snippet: This tasks participants with looking for patterns in an array of shapes - and is thought to be a good measure of intelligence .
highlights_snippet: In total, more than 200,000 participants in IQ tests were studied .
  