Left-align the components in the column. If labels are left-aligned, they are easier to scan. This is useful if users are likely to search for particular labels. In contrast, if labels are right-aligned they are closer to the visual focus when users scan components. Usually we recommend right-aligning labels.
Some applications have two columns of identical components.
For example, in a medical application the columns might represent a patient's characteristics before and after treatment. If the corresponding components are placed next to each other, there is no need for two sets of labels. One set of labels is sufficient. The labels can be placed to the left of the components or centered between components. We have seen both arrangements in existing applications and we have no data on their relative advantages.