A critical investigation of ISO 11948-2 and ISO 11948-1 for predicting the leakage performance of small disposable incontinence pads for lightly incontinent women

Abstract

ISO 11948-2--an international standard laboratory method developed to predict the leakage performance of small disposable pads for lightly incontinent women--was investigated. The repeatability and reproducibility (precision within and between laboratories, respectively) of two variants on the method were found to be poor. The coefficient of variation for each method variant in each laboratory (two laboratories ran each variant) was higher than 40% for about half the 12 products evaluated. Results differed by up to 94% between laboratories for a given product. The ability of the method to predict the leakage performance of pads was investigated by measuring correlations between the clinical evaluations of the 12 products, and technical evaluations using ISO 11948-2. Correlations were very weak (r < or= 0.487). Accordingly, it is recommended that 11948-2 is withdrawn. A second international standard method (ISO 11948-1)--developed for evaluating large pads, but sometimes used on small ones--was also investigated. Correlations between the clinical evaluations of the 12 products and technical evaluations using ISO 11948-1 were weak (r < or = 0.560). Accordingly, it is recommended that ISO 11948-1 is not used for evaluating small disposable bodyworn pads for women.