Performance of Tablet Breaking Strength Testers I: Intralaboratory Comparison and Prediction

Two motorized and two manually powered instruments were used to measure the breaking strength of tablets of three different shapes, each of two sizes and each at three different target breaking strength values. The experimental results were statistically analyzed. The uniformity among breaking strength testers was compared and these results are presented. A high correlation among devices was observed, allowing for the derivation of regression equations which could be used to predict precisely the breaking strengths from one instrument to another. Manually operated instruments tended to yield lower and more variable values than those of their electrically powered counterparts. Tablet shape and size were also found to affect the uniformity and consistency of tablet breaking strengths.