Adding a Treatment
Treatments provide a description of a study’s treatments. Any specific information such as rate of fertilizer application should be recorded in the managements table. In general, managements are recorded when Yield data is collected, but not when only Trait data is collected.
When not to use treatment: predictor variables that are not based on distinct managements, or that are distinguished by information already contained in the trait (e.g. site, cultivar, date fields) should not be given distinct treatments. For example, a study that compares two different species, cultivars or genotypes can be assigned the same control treatment; these categories will be distinguished by the species or cultivar field. Another example is when the observation is made at two sites: the site field will include this information.
A treatment name is used as a categorical (rather than continuous)
variable: it should be easy to find the treatment in the paper based on
the name in the database. The treatment name does not have to indicate
the level of treatment used in a particular treatment - this information
will be included in the management table.
