From the NTSB statement:
The FDR data indicates that the stick shaker activated at 130 knots, which is consistent with the de-ice system being engaged. FDR data further indicate that when the stick shaker activated, there was a 25-pound pull force on the control column, followed by an up elevator deflection and increase in pitch, angle of attack, and Gs. The data indicate a likely separation of the airflow over the wing and ensuing roll two seconds after the stick shaker activated while the aircraft was slowing through 125 knots and while at a flight load of 1.42 Gs.
Clearly, the aircraft was pitched up right after the stick shaker activated. This was most likely caused by the pilot.
A preliminary examination of the airplane systems has revealed no indication of pre-impact system failures or anomalies.
I've stated previously that perhaps this previous Saab 340 pilot thought he was experiencing a tailplane stall, because the stick shaker activated at about 10 degrees flap, as the flaps were transiting from 5 degrees to 15 degrees (after 15 degrees flap was selected). It's unfortunate (if the pilot was thinking about tailplane stall) that the airspeed decayed to the stick shaker warning WHILE the flaps were in transit. We know the flaps were immediately retracked after this, never reaching 15 degrees, as previously stated by the NTSB. This also indicates to me "tailplane stall" in the mind of the pilot, since flap changes can cause a tailplane stall.
The CVR hopefully can reveal more about this possibility, in light of the NTSB's desire to discuss sterile cockpit rules in the public hearings. Fatigue could also explain why a stick shaker warning could be interpreted as "tailplane stall" in the pilot's mind, as the NTSB want to discuss fatigue as well.