For example, this title is ok:
But it only includes the intervention (low-air loss beds), the outcomes (pressure ulcers) and the design (systematic review).
This title is better:
Notice that this title includes both the intervention and the comparator (foam mattresses). It also adds in the population (nursing home patients).
Of course, if you have character limits for your title, you might have to remove some of the elements of PICO(D). Do that by removing the least important elements first. In this case, you might start by removing the population (nursing home patients).