Improving the Global Burden of Disease (GBD) Study burden estimation requires understanding of the factors that influence estimate uncertainty. We examined how the availability of local research studies and vital registration is associated with the uncertainty around GBD estimates for neurological disorders in the Middle East and North Africa (MENA).

Using data from the GBD 2023 Sources tool, we described the availability of local research papers and vital registration data across neurological disorders and MENA countries and its association with the uncertainty in GBD prevalence, incidence, and mortality estimates. We defined uncertainty as the half-width of the 95% uncertainty interval divided by the estimate.

All neurological disorders had at least one local data source in more than one MENA country, although these sources were unevenly distributed across countries. The uncertainty of prevalence and incidence estimates was similar among socio-demographically similar countries. Local research studies provided only a small additional reduction in prevalence estimate error (adjusted β = -1.58%; 95% CI: -2.92, -0.25) and had no significant effect on incidence estimates. In contrast, uncertainty in mortality estimates was similar among geographically bordering countries and only influenced by the availability of local vital registration data (adjusted β = −18.21%; 95% CI: -24.07, -7.95).

By analyzing the gaps in the current availability of local data in each MENA country and for each neurological disorder, we developed targeted recommendations to improve burden estimation across the region.