A potential strength of PIT is that it is just as effective if not more so than current treatments at improving depressive symptoms. Research support comes from Elkin, who found that when compared to CBT, PIT is just as effective at treating depression. This is strength because PIT provides an alternative treatment to CBT that is just as effective. We must therefore be more trusting of the PIT therapy for depression as it provides another treatment for people who struggled with CBT that is just as effective. Meaning that more people can have their symptoms improved, in theory.
However, a weakness of Elkins findings is that just because PIT is as effective of CBT, this is a weakness because CBT may not be effective in the first place, making them both equally as ineffective. Therefore we must be cautious in trusting this therapy of depression as it may be used based on those findings even though it potentially could be very ineffective. This could lead to very serious consequences which could be dangerous for the patient.
Furthermore even though PIT as often been found to be effective research has also shown that after 12 months the majority of patients revert to their previous state suggesting it may not be a completely curative treatment, instead it acts in the same way as drug therapy does in reducing the symptoms as more of a palliative treatment.
On the other hand BDT is also a common therapy for depression, as the treatment isn’t as time consuming as its counterpart and instead focuses on negative emotions and intervenes in them. Whereas often therapies will use abreaction to help with vivid recall allowing the patient to release their feelings through catharsis.
Despite the fact that research such as Leichsenring has shown that BDT is at least as effective as CBT, there is still only a small amount of research for the therapy due to the lack of practitioners for the therapy compared to the number of psychologists trained in CBT. Although this may be because CBT can often be used in group therapy allowing for a larger sample size, and that measuring thought processes are easier to than repressed emotions.
This means than even though the majority of research on BDT has shown it to be effective compared to CBT the sample sizes are much smaller due to the way in which the treatment must be delivered, and the effort the psychologist must put in to educating the patient. This increased effort may also mean psychologists would be more likely to only publish data that is positive to justify the research, meaning some research may be subject to researcher bias.