Reconciling ACS Disability percentages with BFRSS percentages

This could be due to a difference in the overall definition of disability between the two surveys or in the way the questions are asked then counted (eg, "are you disabled" versus "do you have any the following issues...", which is then treated as the basis for disability).  

This is not the only discrepancy of this type.  There is often a wide gap between the number of children who receive special education services through an IEP versus those counted as disabled by the ACS.

Following up on Cliff Cook's response, can Adam Bickford research and post how the disability is defined in both surveys? That would be beneficial for the record for the rest of us. (Mind you, there's also NHIS, the National Health Interview Survey, a nationwide in-person survey that is generally considered to be higher quality than BRFSS but of course smaller sample size; see https://nhis.ipums.org/nhis/. It will probably have yet another different definition of disability and correspondingly a different estimate).

Following up on Cliff Cook's response, can Adam Bickford research and post how the disability is defined in both surveys? That would be beneficial for the record for the rest of us. (Mind you, there's also NHIS, the National Health Interview Survey, a nationwide in-person survey that is generally considered to be higher quality than BRFSS but of course smaller sample size; see https://nhis.ipums.org/nhis/. It will probably have yet another different definition of disability and correspondingly a different estimate).