Are deeply nested conditionals less readable?

There is some debate over the effect of using deeply nested control structures upon programmer comprehension. In order to test the effect of deeply nested IF-THEN-ELSE statements, we split 148 computer science students of varing backgrounds into two groups. One group received a listing of a program that made excessive use of deeply nested control structures. The other group received the listing of a functionally equivalent program that did not make use of deeply nested IF-THEN-ELSEs. Both groups answered the same list of questions about the program they were assigned. The results indicate no significant difference in the average performance on the questions between the two groups.Keywords: Program Comprehension; Program Complexity; Control Flow Complexity; Experimental Computer Scienc