Does psychotherapywork?

There are over 100 different types of therapy available in the US.For a long time, researchers showed little interest in evaluatingthe effectiveness of any of them. After all, if people want tospend their money to be hypnotized, or discuss their dreams, whyshould anyone object? Later, however, the US Congress held longdebates about national health care, including the possibility ofsetting up a national program to pay the costs of psychotherapy.Before saddling taxpayers with those costs, the lawmakers wanted toknow how effective psychotherapy really is.

The following studies incorporate progressively more complexexperimental methods. Critically examine each for flaws and discussthose here.

Study 1: This studyasked several therapists to state how seriously disturbed their newpatients were. Six months later, we asked them again. Nearly all ofthem declare that the majority of their patients are vastlyimproved. Does this answer the question? Why or why not?

Study 2: Assumestudy 1 is repeated using judges that were not the psychotherapiststhemselves but other therapists (\"blind observers\") who meet theclients for the first time to evaluate their psychological healthat the start of the study and again six months later. This studyreports that 75% are better adjusted, 15% are unchanged, and 10%are worse. What can we conclude?

Study 3: This studyrepeated study 2 but included an experimental and control group.The experimental group included troubled participants that went totherapists and the control group included troubled participantsthat did not see therapists. Participants were rated by a \"blind\"observer at the start of the study and again six months later. Theexperimental group has shown greater improvement than the controlgroup. Can we draw a firm conclusion?