Whenever using an index to local record, become familiar with the way in which the index is organized, what all the column headings mean, and who from the records actually appears in the index.
Some indexes are alphabetical only by first letter of last name. Some index by first letter of last name and partially by the first letter of the first name. Some group names by the first few letters of the last name.
Indexes to local records, since they are created at the local level can vary greatly from one location to another even within the same state. That difference can be even greater when indexes are created within different states.