Question

Research comparing the effectiveness of psychotherapists who received training in a number of different areas (psychology, psychiatry, counseling, social work) has demonstrated

psychologists and psychiatrists tend to be more effective than counselors and social workers
clinical psychologists tend to be more effective than psychiatrists
psychiatrists tend to be more effective than clinical and counseling psychologists
no reliable association exists concerning therapists professional training and effectiveness

Answer 1

no reliable association exists concerning therapists' professional training and effectiveness

Step-by-step explanation:

Psychotherapy is designed based on the assumption that the problems which exist within the patient is caused by underlying unconscious thought that influence the patient's behavior.

The problem is that we can't really have a method to proof whether the diagnosis that the therapists made is correct. This make psychotherapy has notoriously low rate of success (only around 26.5%)