Does the target of a grab-based power remain grabbed after the attack?

From my understanding a grab-based power involves the following:

  1. The user spends a standard action to make a grab attack on the target.
  2. The target can resist the grab as per the normal grab action rules, using Strength or Dodge.
  3. If the target fails to resist the grab he then needs to resist the normal effects of the power (for example toughness for a damage power)

My question is whether this grab attack that is made as part of using the power is supposed to be an actual grab attempt that remains in effect if the target fails the grab resistance check or merely an additional resistance check that must be overcome that is based on grabbing rules.