Dodo bird verdict

Some people say that all empirically validated psychotherapies have similar outcomes, no matter what their components are. This is known as Dodo bird verdict, or Dodo bird conjecture in psychotherapy. Saul Rosenzweig introduced the concept in 1936, and named it after Dodo, a character from Lewis Caroll's book Alice in Wonderland. The topic is controversial. It only became widely known with new research evidence, in the 1970s.
History.
Saul Rosenzweig introduced the terminology in 1936 to illustrate the notion that all therapies are equally effective. Rosenzweig borrowed the phrase from Lewis Carroll's 1865 book, "Alice in Wonderland". In the setting, some characters become wet and, in order to dry themselves, the Dodo Bird decided to issue a competition: everyone was to run around the lake until they were dry. Nobody cared to measure how far each person had run, nor how long. When they asked the Dodo who had won, he thought long and hard and then said, "Everybody has won and all must have prizes." In the case of psychotherapies, Rosenzweig argued that common factors were more important than specific technical differences, so that (on the Dodo bird conjecture) all therapies are winners; they all produce equally effective outcomes.
In 1974, Lester Lubarsky, Barton Singer and Lise Luborsky published the results of one of the first comparative studies: They showed that there were only few significant differences in the outcome of different psychotherapies. After the study was published, there were many other similar studies: some agreed with the Dodo bird verdict, others didn't.
In very basic terms, the Dodo bird debate is focused on the following: Can different components of specific treatmenrs lead to the fact that some of these treatments perform much better than others, for specific disorders? Those supporing the Dodo bird verdict say that all treatments are equivalent, because they all have "common factors". Critics say that the different therapies use different techniques, and these differences are important. For this reason, for a given problem, some therapies produce results that are not equivalent to the others.
Importance.
The outcome of the Dodo bird debate is very important for the future of clinical psychology. For one, policymakers have to know how effective each existing psychotherapy is in order to be able to decide which therapies should be supported. This controversy may also lead government officials to no longer fund psychological treatments and other public health measures.