Center Treatment Response Freq 
 a 1 1 11 
 a 1 2 25  
 a 2 1 10  
 a 2 2 27
 b 1 1 16 
 b 1 2 4   
 b 2 1 22  
 b 2 2 10
 c 1 1 14 
 c 1 2 5   
 c 2 1 7   
 c 2 2 12
 d 1 1 2  
 d 1 2 14  
 d 2 1 1   
 d 2 2 16
 e 1 1 6  
 e 1 2 11  
 e 2 1 0   
 e 2 2 12
 f 1 1 1  
 f 1 2 10  
 f 2 1 0   
 f 2 2 10
 g 1 1 1  
 g 1 2 4   
 g 2 1 1   
 g 2 2 8
 h 1 1 4  
 h 1 2 2   
 h 2 1 6   
 h 2 2 1