NCVS DGU count

John Briggs writes:

Also, the Crime Incident Report that follows the Basic Screen Questionnaire
seems to elicit details (including defensive responses) regarding only the
most recent of multiple similar reported crime incidents. Questions 2 and 3
ask about the when and where of “this/the first incident” and question 4
asks “Altogether, how many times did this type of incident happen during
the last 6 months?” Then, item 5a states “The following questions refer
only to the most recent incident” and the rest of the questions in the CIR,
including those regarding defensive actions, appear to be constrained by
this limitaion. Would this not necessarily undercount DGUs?

No, though it may result in an overcount.

If a respondent
had been mugged twice in the six month survey period any DGU in the first
incident would be uncounted (because of the 5a limitation) even though both
muggings would be counted by question 4.

But any DGU in the second incident would be counted twice. Collecting
details on only one incident and letting it stand for all the others
will tend to give more accurate answers since the most recent one will
probably be recalled more accurately.

However, this could result in an overcount, since a robbery victim may
respond to a robbery by deciding to carry a gun, thus making it more
likely for them to use a gun for defence in a second robbery within
the six month period than in the first one.