Which Treatment Is Better? A randomized controlled trial was designed to compare the effectiveness of splinting versus surgery in the treatment of carpal tunnel syndrome. Results are given in the table below (based on data from “Splinting vs. Surgery in the Treatment of Carpal Tunnel Syndrome,” by Gerritsen et al., Journal of the American Medical Association, Vol. 288, No. 10). The results are based on evaluations made one year after the treatment. XLSTAT results are given with the table. Using a 0.01 significance level, test the claim that success is independent of the type of treatment. What do the results suggest about treating carpal tunnel syndrome?

Splint Treatment Surgery Treatment 67 Successful Treatment Unsuccessful Treatment 60 Chi-square (Observed value) 9.750 Chi-square (Critical value) 6.635 23 DF p-value 6 alpha 1 0.002 0.01