We compare recent MINERvA antineutrino-hydrogen charged-current measurements to phenomenological predictions of the axial-vector form factor based on fits to all available electron scattering and deuterium bubble-chamber data and to representative lattice-QCD (LQCD) determination by the PNDME Collaboration. While there is 1--2σ agreement in the cross section with MINERvA data for each bin in Q2, we identify three regions with different relevance and opportunity for LQCD predictions. For Q2≲0.2 GeV2, the phenomenological extractions have large number of data points and LQCD is competitive, while MINERvA data have large errors. For 0.2 GeV2≲Q2≲1 GeV2, LQCD is competitive with the MINERvA determination, and both give values larger than from phenomenological extraction. For Q2>1 GeV2, the MINERvA data are the most precise. Our analysis indicates that with improving precision of MINERvA-like experiments and LQCD data, the uncertainty in the nucleon axial-vector form factor will be steadily reduced.

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