Muscular Dystrophy. Data from Rencher (1995), Ex. 5.17

Data were collected in an attempt to find a screening procedure to detect
carriers of Duchenne muscular dystrophy, a disease transmitted from
female careiers to some of their male offspring 
(Andrews and Herzberg, 1985, p. 223-228)
The following variables were measured on a sample of moncarriers and a
sample of carriers:

Group  Noncarrier = 1, Carrier = 2
Age    age
Month  month in which the measurements are taken
Crea   creatine kinase
Hemo   hemopexin
Lact   lactate dehydrogenase
Pyru   pyruvate kinase

The variables Crea and Hemo are relatively inexpensive to measure compared to
Lact and Pyru.
Crea to Pyru may depend on age and month.