Recent studies have shown that the most important factor to consider while buying running shoes in terms of injury risk, is comfort and fit. Every little discomfort issue in a shoe is amplified when running.
If the shoe is too short or too long, too wide or too narrow, if a little stitch in the inside rubs you in the wrong way, imagine dealing with this for thousands of steps, along with your feet swelling because of the impact of the heat, or the little stitch rubbing its way to a proper blister.
To ensure you get the correct-fitting, comfortable running shoe, remembering your feet will swell during the run, try on a range of sizes and brands, and do plenty of indoor walking before making your decision and taking them out on their first run.