In order to complement the search of articles, the references
of the obtained articles were also evaluated for relevant articles.
This resulted of three more relevant studies (12-14), which
were used for the purpose of the present article, despite of the
fact that two of them had a retrospective nature.
Randomised Controlled Trials (RCT), controlled clinical
trials, controlled before and after studies that evaluated enteral
feeding via nasogastric tube (NGT) or percutaneous endoscopic
gastrostomy (PEG) effectiveness were included, and
prospective observational studies were also included. However,
no controlled clinical trials or RCTs were identified. The
authors claim that this was main reason for ethical concerns
because it is not ethical to allow a group of patients to starve
for the purposes of having a control group (4, 9, 14). Hence,
controlled observational studies were used for the purposes of
this paper
Despite the methodological frailty of observational studies, it
is worth noting again that RCT are not suitable for this type of
research for ethical reasons. The limitations of this study design
can be compensated by its methodological quality as assessed
by the Newcastle-Ottawa Scale. This scale focus on 3 pillars
to assess: 1) patient selection (including representativeness of
the exposed cohort, non-exposed cohort selection, exposure
ascertainment and demonstration that the outcome of interest
was not present at start of study), 2) cohorts comparability
on the basis of design or analysis, and 3) outcome (including
outcome assessment, whether follow-up was long enough
for outcome and cohort follow-up adequacy) (16). A total of
9 stars could be attributed to the studies; if they counted for
more than 6 stars, they were considered to be good quality (17).
Table 1 presents the methodological quality assessment of the
considered articles; one may conclude that 78% (7 in 9) of the
publications presented a satisfactory evaluation.