Ail of the prior studies, except for the Infant Health and
Development Project (IHDP). used a single site for data collection,
which limits generalizability of the studies' findings. In
addition, omission of manipulation checks in nearly all the
above studies fails to shed light on whether or to what: extent
the mothers actually processed the information they were
provided and/or the extent to which they participated in the
intervention programs. Two well-designed studies (McCarton
et al., 1997: Resnick, Eyier. Nelson, Eitzman, & Bucciarelii.
1987) implemented programs that included 48 to 100 home
visits in the first few years of life. Although these studies
showed positive outcomes on child developmental outcomes,
the financial and human costs as well as the feasibility in
implementing these programs make it difficult to justify widespread
dissemination. Thus, because a current emphasis in
the health care system Is on cost-effectiveness (Stone. 1998).
it is unlikely that a change in health policy would occur to
include these as service programs tor ail parents