What are the main limitations of the MPI?
The MPI has some drawbacks, due mainly to data constraints.
- The indicators may not reflect capabilities but instead reflect outputs (such as years of schooling) or inputs (such as cooking fuel).
- The health dimension indicators are not consistently collected across countries and overlook some groups’ deprivations, especially for nutrition, though the patterns that emerge are plausible and familiar.
- Child deaths that occurred at any time (instead of in the last 5 years previous to the survey) are used in 11 countries because the survey did not collect the date of child deaths. We are currently working on finding a better alternative to these cases.
- In some situations, careful judgments were needed to address data that was not collected. For example, data on nutrition was not collected for children older than 5 years in both DHS and MICS, data on adult nutrition was not collected in MICS, data on adult nutrition was collected only for women of ages 15 and 49 in DHS (though in a small number of countries it was collected for men), and child mortality was not collected in households without women of reproductive age. In these situations, households without eligible members to be measured for nutrition and without eligible members to report child mortality are assumed to be not deprived in these indicators. This is a strong assumption that may bias the results and we are conducting research to find a better alternative. However, to be considered multidimensionally poor, households must be deprived in at least six standard of living indicators or in three standard of living indicators and one health or education indicator, or in two health or education indicators. This requirement makes the MPI less sensitive to such assumption.
- Intra-household inequalities may be severe, but these could not be captured.
- While the MPI goes well beyond a headcount ratio to include the intensity of poverty, it does not measure inequality among the poor, although a separate measure of inequality has been published since 2019 (variance of individual deprivation scores of poor people). Also, decompositions by groups can be used to reveal group-based inequalities.
- The estimates presented are mostly based on publicly available data and cover various years between 2009 and 2020, which limits direct cross-country comparability.