Milk-and-Dairy-Products-in-Human-Nutrition-FAO

Chapter 7 – Milk and dairy programmes affecting nutrition 277
7.2 Sources and approach to the review
A comprehensive review of the peer-reviewed and grey literature was conducted
to identify milk programmes affecting the nutrition of populations in developing
countries. “Milk programme” was defined as an intervention introduced into a
defined population over a certain period of time that involved milk and affected
nutrition in some manner. Databases searched included: Proquest; PubMed Central;
Science Direct; and Scopus. Coverage was global, although most records were
in English. In addition, web pages from several international agencies and nongovernmental
organizations were searched for grey literature, monographs and
evaluations. Both simple and multifield/advanced searches were used. The following
criteria were used to decide whether to include a programme in the study: 1) milk or
dairy products were part of the intervention; 2) nutrition, and in some cases health
and anthropometry of participants, was affected through the diet; 3) the study was
intended to inform programming (observational/formative) or included an evaluation
that allowed the possibility of inferring adequacy, plausibility or probability
(see following paragraph); and 4) the programme context was a developing country.
Programmes were classified into four levels of inference, to indicate quality of
design and methods. These were, in ascending order of rigour: 1) observational/
formative; 2) adequacy; 3) plausibility; and 4) probability (Habicht, Victora and
Vaughan, 1999). Observational/formative includes those results and findings that
are intended to inform programming strategies or are later used to do so. No
conclusions may be drawn on intervention impact. Adequacy includes studies or
evaluations assessing only whether expected changes occurred. There is usually
no control group, but at least two surveys or measures over time and space are
carried out to assess change. The next level of inference is plausibility, in which
factors operating to influence outcome beyond the programme intervention may be
considered. Some form of control group (historical, internal or external) is generally
used in these quasi-experimentally designed evaluations. The highest level of
inference possible is probability, where the evaluation design is likely to be able to
demonstrate causality. Programme intervention may be linked to outcomes with
a low probability of confounding, bias or chance. Randomized controlled trials
(RCTs) have been the gold standard for this inference, though different techniques
and evaluation designs are becoming more widely accepted to establish attribution
(Victora, Habicht and Bryce, 2004).
Table 7.1 (see Annex) summarizes the programmes reviewed in each of the
four categories. Programmes are organized alphabetically by country name within
regions and then chronologically by date if there was more than one programme or
study per country.
7.3 Dairy production and agriculture programmes
Nutrition is most likely to be affected by dairy production programming via two
pathways: increased milk availability from production leading to increased direct
consumption; and improved access to higher-quality foods as a result of increased
income (Figure 7.1). Whether diet improves as a result of increases in income
depends on the recipient’s understanding the need for good nutrition; if they do
not, the additional income may be used to buy more of the same foods or foods
of lesser quality. Other possible negative effects of dairy production on nutrition