Search Strategy
In this review, we searched for prospective controlled trials
determining the efficacy of the oral adsorbent AST-120 in delaying the
decline of renal function among CKD patients, regardless of etiology. In
terms of outcomes, articles with any one of the following outcomes were
deemed appropriate for inclusion in the review: rate of serum creatinine
increase, rate of deterioration of creatinine clearance, incidence of
dialysis, incidence of kidney transplantation, adverse events or
mortality rate.
We searched for articles in PubMed including MedLine,
Clinicaltrials.gov, and Cochrane databases. Search terms were based on
the components of the research question. Keywords used were as follows:
“chronic kidney disease,” serving as the concept for the population,
and “oral adsorbent,” serving as the concept for the intervention. In
the process of using the databases’ search engines, each of these
concepts were expanded using Boolean operators to maximize search
sensitivity. The term “chronic kidney disease” were combined with its
alternative terms, including its MeSH terms, using the “OR” Boolean
operator. The term “oral adsorbent” were likewise combined with its
alternative term (“Kremezin”) and MeSH counterpart (“AST-120”).
These expanded concepts for the population and intervention were
intersected using the “AND” Boolean operator to narrow down the
search. The retrieved articles were further filtered to only include
prospective controlled trials. Each of the abstracts of the articles
were examined to assess appropriateness for inclusion in the
meta-analysis. Articles that did not reflect the research question, as
well as studies that were not prospective controlled trials, were
excluded.
Specifically, the search entailed the use of the following terms:
(“chronic kidney disease”[All Fields] OR “chronic renal
disease”[All Fields] OR “chronic renal failure”[All Fields]
OR “chronic kidney failure”[All Fields] OR “chronic renal
insufficiency”[MeSH Terms]) AND (“oral adsorbent”[All Fields]
OR “Kremezin”[All Fields] OR “AST-120”[MeSH Terms])