In the 120 women , the sensitivity , specificity , positive predictive value , and negative predictive value of PAMG-1 , IGFBP-1 and nitrazine test were 100 % , 100 % , 100 % , and 100 % , 93.33 % , 98.89 % , 96.55 % and 97.80 % , and 93.33 % , 94.44 % , 84.85 % , and 97.7 % , respectively .