Personally, I use the ProRealTime "SuperTrend" indicator to indicate the current trend... it tends to stay below price on Long trends, and above price on Short trends, and ATR is part of the algorithm for calculating the levels.
In practice, I use SuperTrend on 4-Hr and 1-Hr and 15-min charts to establish a common trend direction, be it Long or Short, then trade only in that direction when Day Trading.