  We point out an issue with Theorem 5 appearing in "Group-based active query
selection for rapid diagnosis in time-critical situations". Theorem 5 bounds
the expected number of queries for a greedy algorithm to identify the class of
an item within a constant factor of optimal. The Theorem is based on
correctness of a result on minimization of adaptive submodular functions. We
present an example that shows that a critical step in Theorem A.11 of "Adaptive
Submodularity: Theory and Applications in Active Learning and Stochastic
Optimization" is incorrect.
