Referral bias in ALS epidemiological studies.

Giancarlo LogroscinoBenoit MarinMarco PiccininniSimona ArcutiAdriano ChiòOrla HardimanJames RooneyStefano ZoccolellaPhilippe CouratierPierre-Marie PreuxEttore Beghinull null

Published in: PloS one (2018)

A trend for referral bias is present in cohorts drawn from ALS referral centers. The magnitude of the possible referral bias in a particular tertiary center can be estimated through a comparison with ALS patients drawn from registry in the same geographic area. Studies based on clinical cohorts should be cautiously interpreted. The presence of a registry in the same area may improve the complete ascertainment in the referral center.

Keyphrases

primary care
end stage renal disease
ejection fraction
newly diagnosed
prognostic factors
case control