The phrase "observed evidence of" is correct and usable in written English.
You would typically use this phrase when referring to tangible evidence that has been seen, such as in a research study or experiment. For example, "The scientists observed evidence of a reaction when the two substances were combined."
Although we did not find any significant association in females, we did observed evidence of association in males for some of the clinical features; however, these associations are not stronger than the overall male-specific analysis.
Meta-analysis was only conducted where there was no observed evidence of a substantial difference in study populations, interventions, or outcome measures on review of the extraction table.
Although hybridization between wolves and golden jackals has never been observed, evidence of such occurrences was discovered through mtDNA analysis on jackals in Senegal and Bulgaria.
This is currently under investigation and we have observed evidence of translational control of Oct-6 in studies in vitro (unpublished observations).
And for the first time, scientists observed evidence of Lewy bodies.
Several weeks earlier, Incandela and his colleagues had announced that they'd observed evidence of the existence of the Higgs boson, which helps explain — this is the version without terms like "top quark" and "the five-sigma signal" — how subatomic particles, and thus all the elementary matter in the universe, acquire mass.
We observed evidence of the excitation of the longitudinal silver plasmon mode in the optical absorption spectra of Ag-SWCNT dispersions, even at the lowest silver concentrations employed.
Rather, we have observed evidence of improved performance on some cognitive endpoints as prenatal MeHg exposure increases in the range studied.
At a very local scale within the Guangdong province, we observed evidence of population structure among dialect groups, probably on account of endogamy within these dialects.
When the diacetylenic type hydrogel containing GO was irradiated upon UV light, a deep blue coloration change was observed; evidence of an effective photopolymerization.
Shining laser light of a specific wavelength on the atoms, they observed evidence of an emerging up-down-up-down spin pattern.
