Full Report - Research for Development - Department for ...

5. Strengths and limitations
Summary
Limitations include:
Bias towards English language literature
Bias against modelling-based economic evaluations
Strengths and limitations
Restriction to maternal or infant mortality outcomes, excluding non-mortality
health outcomes for mothers and infants
Problems in identifying ‘poor’ populations and reliance on the use of proxies for
‘poor’
5.1 Search strategy
There are a number of limitations in our review. One key issue is a bias towards
English language literature. By restricting our search strategy to largely English
language databases, we may have missed relevant studies in other languages, this
is despite the fact that some databases do provide English language abstracts for
non-English language papers. We have tried to mitigate against this by examining
relevant papers in French, Spanish and Italian. Moreover, while we do not have the
resources for additional translation, we have also sought to identify potentially
relevant papers in other languages whose English language abstracts appear
relevant.
In developing and refining our search strategy, it became clear that it would be
difficult to come up with a comprehensive set of terms to cover the many different
definitions of poverty and urbanicity. We sought to counter this risk by not
including any specific poverty or urbanicity terms in our search strategy, and
instead sought to identify studies that looked at maternal and child health in our
target countries and then to determine whether these studies did focus on our
target population. Our study protocol indicated that we would make our initial
decisions on inclusion/exclusion on the basis of study abstracts/summaries.
However it had to be acknowledged that relevant papers might not provide
sufficient detail on target population to judge whether a paper focused on urban,
poor populations from the abstract alone. We tried to account for this by erring on
the side of retrieval of full text papers where a study appeared relevant in all
respects other than having an indication of geographical location or socio-economic
status of the target population.
Our primary search strategy may also not have been sensitive enough to pick up
economic evaluations which were based on modelling rather than empirical
studies; while we did search both Econlit and the NHS Economic Evaluation
Database, a supplemental search of several key databases making use of key
economic evaluation terms was conducted to see whether any additional studies
could be identified, including the Office of Health Economics Health Economics
Evaluation Database (HEED). Given the limited number of effectiveness studies that
looked at interventions specifically for urban populations and reported maternal
and/or infant mortality outcomes, this is not surprising.
Another challenge has been the limited functionality of some databases, which in
some cases have made it difficult to construct complex search strategies and/or to
import records electronically into EndNote. In some cases, the lack of functionality
What are the effects of different models of delivery for improving maternal and infant
health outcomes for poor people in urban areas in low income and lower middle income
countries? 53