an examination of the role of antenatal care attendance in ...

Where Y = In P, is the probability of experiencing an adverse birth outcome.
}-P..
P X\ + P X7 + — P X are estimated coefficients associated with individual level
characteristics of experiencing the risk of recent adverse birth outcomes, and // are the
disturbances in the regression models. The assumption in this analysis is that EI//J= 0
(Zambuko and Mturi 2005).
Missing values are a big concern in data analysis and the dilemma is whether to include or delete them
in the data. Including the missing values in the analysis may result in the distortion of the result, can
inflate or deflate summary statistics and can destroy the ordinal and interval character of the variables.
While on the other hand, the exclusion of missing values may introduce bias in the sample and may
reduce it to non-acceptable levels (de Vaus: 2002). In order to avoid confusion and distortion of results,
missing values were therefore excluded in the analysis, with the assumption that the distribution for
missing values was normal. The deleted data accounted for 10% of the target population.
3.5 Limitations of the study
The following limitations should be taken into account when interpreting the results for this study.
Firstly, data used was retrospective in nature, thus there is the possibility of recall bias. To address this
limitation, the researcher selected data from January 1997 to December 1998 in order to minimize
recall bias.
Secondly, the demographic and health survey did not collect information on critical factors that have
been shown to influence frequency and timing of antenatal care visits. As a result, the study could not
examine the role of environmental factors such as distance and transport to the antenatal care facility,
which might be critical factors determining the frequency and timing of antenatal care visits.
The data for the study is primarily quantitative and does not allow for the exploration of issues in any
detail and in particular the reasons behind the late initiation of antenatal care. In addition, some
variables were not readily available and as a result it was necessary to construct new variables.
Moreover, the dependant variable includes caesarean as an adverse birth outcomes, however, caesarean
section can be a choice of convenience irrespective that there is no adverse effect on the baby or the
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