Fluoride data story

Last edited on 27th by gs/ gs . - Host home page:http://www.statlab.uni-heidelberg.de
Quade (1992) reports data abtained by Cartwrigtht, Lindahl and Bawden (1968) from an experiment to reduce dental caries.
Two treatments,
stannuous fluoride
acid-phosphate fluoride
and a placebo treatment
distilled water
are used in a two-year study. 69 female children completed the study. The number of decayed, missing or filled teeth (DMFT) is reported before (B) and after (A) the study; the response to be analyzed is the difference Y=A-B.
The initial DMFT count B and the age X in years at the beginning of the study are covariates. There may be an additional effect from the institution where the child resided, coded 1, 2, 3.

DMFT difference versus age

Data file:fluoride.data
Source: D. Quade: Nonparametric Analysis of Covariance by Matching. Biometrics 28 (1982) 567-611.
H.V. Cartwright, R.L. Lindahl & J.W. Bawden: Clinical findings on the effectiveness of stannuous fluoride and acid phosphate fluoride as caries reducing agents in children. Journal of Dentistry for Children 35 (1968) 36-40.