"across the groups" is a correct and usable phrase in written English.
For example, you could say, "The research findings were consistent across the groups."
The oocyte maturation rate was same across the groups.
DLMO and HSO were not different across the groups.
Finally, the groups merged and attempted to conduct commerce across the groups.
Infants and children were excluded because of the need for homogeneous comparison across the groups.
Genders were not split similarly across the groups (χ2(4) = 928, p < 0.001).
No significant difference in terms of transfer of learning scores was observed across the groups.
These results however, are limited by the heterogeneity of illness severity across the groups.
Monoamine oxidase A (MAO-A) was different due to treatment across the groups (p = 0.028).
Across the groups, the aortic annulus size, degree of calcification, and cover index were comparable.
Treatment differentially affected monoamine oxidase B (MAO-B) across the groups (p = 0.05).
Major features were comparable across the groups.
