· multiple reviewers to select the articles to

Literature searches were made to find articles
conducting randomized control studies using folic acid, folate, or folic acid
with other supplements, and testing its effect on adenomas and colorectal
cancer. The participants can either possess or not have a history of colorectal
related diseases, and the control group cannot be given folic acid. Out of the
eight databases searched, only three studies were used to perform
meta-analysis. The meta-analysis results concluded that there is no
statistically significant effect of folic acid reducing the recurrence of
colorectal adenomas or colorectal cancer for any population.

This article reviews the results of other primary
research papers that studied the effect of folic acid on colorectal adenomas or
colon cancer recurrence, which makes this article relevant. The researchers had
multiple reviewers to select the articles to be included into the review, so
all chosen articles were appropriate and fitted the criteria. Data was
extracted and used to calculate relative risk, risk difference and confidence
intervals, so that the conclusion obtained would not be due to random chance. However,
a concern was that the three chosen articles had short trials and a short
duration follow up period.  

 Participants who undergone previous double-blinded
placebo control trails and diagnosed with colorectal adenomas were put into a
randomized intervention trail. Participants were given either 5mg of folic acid
a day or a placebo and then followed up after 3 years. To establish
associations, polyps were removed at baseline colonoscopy, and measurements
were made by using colonoscopy to determine whether there was a differing
number of recurrent adenomas. It was found that participants given the 5mg
folic acid supplement was associated with a statistically significant reduction
of recurrence colorectal adenomas. Thus, the results showed that 5mg of folic
acid supplement a day may prevent the recurrence of colorectal adenomas.

This article investigates the research question and
provides somewhat good evidence for its results, which makes this article
relevant. The experiment studied 94 participants around the age of 44-80 and
followed up for 3 years, which is a small and diverse sample size with a short-termed
duration. However, during the study participants were monitored and contacted
through phone to assess any problems, which allows researchers to obtain good
results and prevents factors from influencing the study.


       Participants from prospective cohort studies were put
into a double blind randomized intervention trail, where they were given either
1mg of folic acid a day or a placebo. Measurements were done by the diagnosis
of adenoma during the study, followed by studying the site of adenoma, stage,
and the amount of recurrence. Plasma folate concentrations were also measured
at baseline to determine its associations. In participants with low plasma
folate concentrations, it was found that those given the folic acid supplement
had a reduced risk of recurrent adenoma compared to those given the placebo; in
participants with high folate concentrations, the supplement provided no
significant health benefits. Overall, the results showed that 1mg of folic acid
supplement a day does not reduced the risk of recurrent adenoma. This article is relevant because it investigates the
research question and provides good evidence for its results. The experiment
was well designed and studied 672 participants around age 50-78 and followed up
for 3-7 years, which provides a good sample size and study duration. However,
the follow up of this study utilizes questionnaires which is not the best
method to obtain accurate results and could introduce confounding factors into
the study.