How to identify advantages and disadvantages of LED chips?

Through the experiment, to see the decline of light and brightness .Five steps:

a. Flux.
b. Lumen.
c. Chromatic aberration.
d. Production process.
e. Quality assurance.

Test white light:

a, different chips. b, exactly the same bracket. c, exactly the same phosphor.d, exactly the same proportion.e, aging in the same timef, at the same time test.
Above can identify it!