When it comes to external disks you probably cannot. The only thing one can say for sure is how many LVM mirror copies exist in a VG and whether the data is LVM striped. However, as any sort of RAID that comes from some external storage box is transparent to the OS there is no way to tell whether the underlying physical disks are organised as RAID-XY. To AIX it is just hdisk devices.
I.e. if you see two LV copies in your VG you might think it was just RAID-0 while under the mirrored hdisk devices some RAID-5 organised disks exists.