A therapist is wanting to understand her client better, as a result, he turns to a number of resources such as reading previous files, speaking to client's medical doctor and possibly family members. Which research method is the therapist engaging in?

Ittle jake is strongly bonded to his mother. in fact, he has a difficult time letting her out of his sight. when his mother must leave him in daycare to go to work, the daycare provider calls because jake is inconsolable. since being placed in daycare, jake has also refused to sleep alone. what disorder do jake's symptoms suggest?