Strengths & Limitations
The researchers in many of the above studies have recognised the need
for a global approach to the management of CS, with results being
amalgamated from studies across multiple continents. It is worth noting,
however, that the lack of multivariable analysis in some of these
studies from the meta-analysis prevented independent predictors of ICD
appropriate/inappropriate therapy to be elicited. As discussed earlier,
there was little data available to reflect the wide-ranging consortium
of patients that can be affected by CS, and as such further determine
which ethnic groups may be at lesser or greater chance of appropriate or
inappropriate therapies. Future studies should collect data that spans
across a broad array of ethnic backgrounds to capture a true reflection
of the disease. Another limitation common to several CS meta-analyses is
the risk of data overlap. Patient identifying features had been removed
due to lack of consent, and as such there will certainly be inaccuracies
in results, particularly given the relatively small sample size. As well
as this, the retrospective study design lends itself to objectively poor
result quality. Finally, although previously discussed as an effective
proxy in light of no better alternative, the use of “appropriate
therapy” as a surrogate endpoint is not a true representation of SCD
and is generally accepted to be an imperfect tool that likely
over-estimates risk.