Multivitamins : Use or Misuse?

Variation: use it or misuse it-replication and its variants.

• Variation between measurements may be reduced if sampling is not random • Fixed factors can reduce variation • Replicates are repeated measurements from within an experimental unit • Replication means that samples can no longer be considered random • Comparisons of replicated values require correction, usually by reducing the effect of sample size • Correction requires knowledge of the intra-...

Corticosteroids in rheumatology: use, misuse or plain abuse?

Dentists' use, misuse, abuse or dependence on mood-altering substances.

The Use and Misuse

Orthogonal regression is one of the standard linear regression methods to correct for the eeects of measurement error in predictors. We argue that orthogonal regression is often misused in errors-in-variables linear regression, because of a failure to account for equation errors. The typical result is to overcorrect for measurement error, i.e., overestimate the slope, because equation error is ...

The primary prevention of birth defects: Multivitamins or folic acid?

Periconceptional use of folic acid alone or in multivitamin supplements is effective for the primary prevention of neural-tube defects. The Hungarian randomized and two-cohort controlled trials showed that periconceptional multivitamin supplementation can reduce the occurrence of some other structural birth defects, i.e. congenital abnormalities. These findings were supported by many, but not a...