Sentence examples similar to pre-existing differences among groups from inspiring English sources

To reduce the effects of pre-existing differences among individuals in mechanical responsiveness, the withdrawal thresholds were also normalized by subtracting each value on the treated (ipsilateral) side from the corresponding value on the contralateral side.

In quasi-experiments random assignment is not possible and statistical control of pre-existing differences between groups has to be carefully exercised.

A matching procedure would potentially have avoided these pre-existing differences between groups.

Inferential statistics confirmed no pre-existing differences between groups in the learning phase, before commencing rTMS (data not shown).

Possible disturbing differences between the groups could be checked via measurements at the beginning of the courses (see the results of the check in the Check on pre-existing differences between the groups section).

What this means, essentially, is that pre-existing differences between the groups being compared actually account for what look like treatment effects.

The improper matching of the groups inevitably introduces susceptibility bias, which is defined as the difference in prognostic expectations due to pre-existing differences between and/or among treatment groups.

First is the use of naturalistic observational data to compare antipsychotic treatment groups, because observed group differences in rates or duration of monotherapy could result from pre-existing differences between the treatment groups rather than differences in medication choice.

Comparison of the pre-treatment phase of Experiment 1 and the control heifers in Experiment 2 revealed no significant differences between the two groups, indicating that there were no pre-existing differences between animals in the two experiments.

Our analysis controls for differences between the places by using a comparison group of older kids who were already in school when the show came on the air — we use those older kids to difference out any pre-existing differences in educational outcomes for kids in different cities.

Therefore, between-group differences in reading speed under AMPH do not reflect pre-existing differences under placebo.