The Context of HIV Risk Among Drug Users and Their Sexual Partners

about transfusion clarified the meaning of and the distinction with the
subsequent question on blood donation.
Concern for the social context implies a recognition of the variability of
human behavior. Some things are done with some people at some times.
To obtain complete and accurate accounts, time (e.g., last time, first
time), type of relationship, and type of activity (when, what, with whom)
need to be specified in inquiries into risk behaviors and risk exposures.
Many are guilty of framing questions to ask about what the respondent
usually does, which elicits answers that depend on the varying ability of
respondents to abstract and generalize about behavior.
The serendipity or new knowledge principle discussed earlier as a
substantive issue has technical implications as well. Observations
(whether verbal or visual, structured or unstructured) should be broad
enough to capture unanticipated responses. Some examples have been
given above.
Changing temporal and spatial (geographic) dimensions of HIV/AIDS in
the second decade exact technical considerations for data collection and
design, as well as substantive considerations. How frequently must new
data be collected to capture changing incidence and prevalence, vectors
of infection, and rates of infection? Spatial and geographic concentration
of infection and the requisite consideration of contextual factors require
integration of data from different sources which are often recorded in
different units of observation.
By way of example, in attempting a test of neighborhood influence on
HIV rates in the longitudinal African-American study, the area HIV rates
that were available were in broadly defined neighborhoods, which
included up to eight zip codes in a single neighborhood, and between
4 and 45 census tracts within one zip code. Special permission and
requests were required in order to obtain infection rates at the zip code
level.
The contextual parameters that were sought included crime statistics
(which were available at the police precinct level) and socioeconomic
characteristics (provided at the census tract level). Zip codes appeared to
be the most useful level for uniform measurement, since that was the
smallest geographic unit for reporting AIDS cases. However, these areas
do not embrace census tracts in an orderly fashion. Even though they are
smaller, census tracts are frequently split between two zip codes and
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