Bone Mineral Density Data consisting of 112 girls randomized to receive calcium og placebo. Longitudinal measurements of bone mineral density (g/cm^2) measured approximately every 6th month in 3 years.
A data.frame containing 560 (incomplete) observations. The 'person' column defines the individual girls of the study with measurements at visiting times 'visit', and age in years 'age' at the time of visit. The bone mineral density variable is 'bmd' (g/cm^2).