Abstract:
:This article re-examines parametric methods for the calculation of time specific reference intervals where there is measurement error present in the time covariate. Previous published work has commonly been based on the standard ordinary least squares approach, weighted where appropriate. In fact, this is an incorrect method when there are measurement errors present, and in this article, we show that the use of this approach may, in certain cases, lead to referral patterns that may vary with different values of the covariate. Thus, it would not be the case that all patients are treated equally; some subjects would be more likely to be referred than others, hence violating the principle of equal treatment required by the International Federation for Clinical Chemistry. We show, by using measurement error models, that reference intervals are produced that satisfy the requirement for equal treatment for all subjects.
journal_name
Stat Methods Med Resjournal_title
Statistical methods in medical researchauthors
Gillard Jdoi
10.1177/0962280211426617subject
Has Abstractpub_date
2015-12-01 00:00:00pages
788-802issue
6eissn
0962-2802issn
1477-0334pii
0962280211426617journal_volume
24pub_type
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