1、例 7-1 某医院欲比较异梨醇口服液（试验组）和氢氯噻嗪+地塞米松（对照组）降低颅内压的疗效。将 200 例颅内压增高症患者随机分为两组，结果见表 7-1。问两组降低颅内压的总体有效率有无差别？表 7-1 两组降低颅内压有效率的比较组别 有效 无效 合计 有效率（%）试验组 99(90.48)a5(13.52)b104 )(ba95.20对照组 75(83.52)c21(12.48)d96 c78.13合计 174 )(26 )(200 n87.00Chi-Square TestsValue dfAsymp. Sig. (2-sided)Exact Sig. (2-sided)Exact Si
2、g. (1-sided)Pearson Chi-Square 12.857a 1 .000Continuity Correctionb 11.392 1 .001Likelihood Ratio 13.588 1 .000Fishers Exact Test .001 .000Linear-by-Linear Association 12.793 1 .000N of Valid Cases 200a. 0 cells (.0%) have expected count less than 5. The minimum expected count is 12.48.b. Computed only for a 2x2 table
