The Indian states, including Bihar, Uttar Pradesh and West Bengal, have 421 million “poor” people, the study found.
This is more than the 410 million poor in the poorest African countries, it said.
The Multidimensional Poverty Index (MPI) measures a range of “deprivations” at household levels.
Developed by Oxford Poverty and Human Development Initiative (OPHI) with UN support, it will feature in the upcoming UNDP Human Development Report.
The measure assess a number of “deprivations” in households – from education to health to assets and services.
“The MPI is like a high resolution lens which reveals a vivid spectrum of challenges facing the poorest households,” said OPHI director Dr Sabina Alkire.