THE MAIN PURPOSE OF THE STUDY WAS TO INVESTIGATE WHETHER STOP SIGNS DIFFER FROM YIELD SIGNS IN TERMS OF THEIR ASSOCIATED ACCIDENT RATES, AND WHETHER OR NOT AN INCREASE IN LEVEL OF TRAFFIC CONTROL IS NECESSARILY BENEFICIAL TO TRAFFIC SAFETY AT ALL HAZARDOUS URBAN INTERSECTIONS. THE STUDY IS BASED ON A "BEFORE" AND "AFTER" EVALUATION OF ACCIDENT RATES AT SEVERAL UNSIGNALIZED INTERSECTIONS, WHERE THE LEVEL OF CONTROL WAS CHANGED BECAUSE OF THEIR ACCIDENT HISTORY. IT WAS FOUND THAT ANY INCREASE IN THE LEVEL OF CONTROL AT SUCH INTERSECTIONS TENDED TO CAUSE MORE VEHICLE ACCIDENTS AND FEWER PEDESTRIAN ACCIDENTS ALTHOUGH MOST OF THE CHANGES WERE STATISTICALLY INSIGNIFICANT. SEVERAL POSSIBLE EXPLANATIONS TO THE FINDINGS ARE EVALUATED AND DISCUSSED. IT IS CONCLUDED THAT INCREASING THE CONTROL LEVEL AT UNSIGNALIZED INTERSECTIONS WILL NOT NECESSARILY RESULT IN AN OVERALL REDUCTION IN ACCIDENTS.(Author/publisher).
Abstract