In an experiment to compare two pain relievers, seven subjects took one of the two pain relievers (randomly selected) for two weeks, then switched to the other for another two weeks. They rated their pain level from 1 to 10, with larger numbers representing higher levels of pain. The researchers want to know if there is a difference in the mean level of pain for the two pain relievers. Suppose the p-value for the test is 0.2199. Which of the following is the best conclusion based on this result?