It seems that when using the groups field in reports, it shows every group the person belongs to. Is it possible to have a smaller selection showing? E.g. just wanting to list bible study group they are in, without also listing in same field all the other group they're in. Perhaps using the group category as the narrowing selection.
Thanks for the question.
There is a feature request for this and I'll add your support to this.
For now though I would suggest using a Group People report found under Groups > Reports as this may suit your needs better.
Hope this helps,