Make clear and logical comparisons in your scholarly writing. Illogical comparisons often result from unparallel sentence structure or the omission of key words. 

Consider the following sentence: 

You have higher odds of being injured by a vending machine than a cat.

The sentence has two possible meanings:

You are more likely to be injured by a vending machine than by a cat. 

You (a human) are more likely than a cat (an animal) to be injured by a vending machine. 

To rewrite the sentence with the first meaning, repeat the word “by”: 

You have higher odds of being injured by a vending machine than by a cat. 

To rewrite the sentence with the second meaning, include a verb for the cat (here, “does”) and move the cat earlier in the sentence to emphasize the comparison with “you”:

You have higher odds than a cat does of being injured by a vending machine.

These examples demonstrate that thoughtful attention to word choice and sentence structure lessens the chance of ambiguity in writing.

Logical comparisons are covered in Section 4.10 of the APA Publication Manual, Seventh Edition