Complex sentence: There has been very little published independent research examining the BDT however Nichols, McLeod, Holder, and McLeod (2008) compared the tutor screening battery TSB (a hybrid of the BDT and the DAST) with the LADS.
Split into simpler sentences: There has been very little published independent research examining the BDT. One publication, by Nichols, McLeod, Holder, and McLeod (2008), compared the tutor screening battery TSB (a hybrid of the BDT and the DAST) with the LADS.