Rick, what are the metrics used in the current 'trial'? I use quotes because unless the participants agreed on what to measure and took starting values, there is nothing to put into an ANOVA. Also, large scale observational studies tend to provide too much data, so everything ends up being significant.
Since the "trial" was never officially defined, some of the best stuff will be based on memory. Few folks (including myself) are keeping detailed records on their entire collections (other than inventory).
Inventory by itself is a decent parameter to monitor. Plants in to program, plants out of program. Exit by death exit by sale/trade/gift. Duration of plant in program. Condition/health, age, size when entered into program.
Then specific program details. Feeding rate, feeding concentration, non-feeding watering rate, chemistry of base irrigation water, potting format and materials, humidity control? temp control? light control?
You can start the "trial" in the future by having each participant select 50 or so plants with matching pre-program plants that are now dead for "before and after" comparisons.
That last point is pretty much what is going on informally now. For instance a typical flasking from Troy Meyers holds about 25 plants. I can go back through my flasking records at TM (which are better than my home records) and count the numbers of seedlings that entered my pre-klite program, and count up the numbers that died vs how many made it to blooming, and compare that to the number making it to blooming now.
There was a post started by Eric Muehlbaur several years ago called "tombstones" showing all the pot tags for all the plants purchased and dead. I have a pretty hefty handful myself. A simple metric would be to count plant tags per year, pre klite and post klite (normalized to total inventory).
There's lots of creative ways to measure sublethal performance too. Leaf length, rate of new growths, total number of leaves per pot, numbers of flowers. Time to first flower, age of new growth to flowering.
You could count things like $ spent on disease and pest control. Frequency of health interventions (normalized to total inventory).
These are all ideas that occur to me while I work with my collection. But since this is my hobby, I just keep the info in my head. If you can get people to write it down or file into excell spread sheets, then you can do stats on it.