In a double-blind experiment neither the researcher nor the participants know who belongs to the control group and who belongs to the experiment group. This helps to eliminate conscious and unconscious bias by experimenter and participants. One variable is manipulated to get a true experiment while other variables are held constant. These trials establish the efficiency of a treatment as well as learn about its side effects. Administering this treatment has been proven to have powerful psychological effects on the participant which is known as placebo effect.
Though randomized controlled trials are criticised by some experts these trials are used in psychological research as a means to establish results effects and side effects of a treatment as analysed in a report Psychotherapy and the placebo effect (Rosenthal, D and Frank ,J. D). Randomized controlled trial is designed to make decisions that address questions like if we have disorder X is treatment A or treatment B going to be effect to treat the disorder? There is always a need to know if there is an alternative treatment and randomized trials help to make a decision the treatment is effective or not.
It has been found that placebos are as effective as other ingredients in the reduction of symptoms and distress. In a study of cold vaccines by Diehl, Baker and Cowan (1940 there was a 55 percent reduction in yearly colds among those who received the vaccine and 61 percent among those who injections of isotonic sodium chloride solution. In another study by Jellinek 60 percent of 199 subjects with chronic headaches received relief from a placebo on one or more occasions.
Although placebos have no medical benefits they have been proven to reduce anxiety, ain and depression and as result therapists need information about comparative treatments that are efficient and randomized trials are able to give answers to these questions. It is essential for therapists to have knowledge of the results of randomized controlled trials the pharmacotherapy and the psychotherapy. Knowing the outcome of an active agent in treatments enhances physicians ability to relieve their symptoms as well as improve patients way of life as well. Harmful treatment may be administered without trials to provide efficient treatment information.
Therapists will have information on treatment options or alternatives to offer patients as randomized controlled trials scientifically back their recommendations. Randomized trials help to show that therapy is better than no treatment. It is therapists ethical responsibility to inform patients of findings and treatments available. Randomized trials reduce bias as the participants are randomly selected and do not know which group they belong to during a trial. In an experiment of mephenesin versus placebo over a four two week period, the first two weeks showed a decrease in distress following placebos in the first two weeks.
A slight increase in distress occurred , statistically insignificant but the effect of placebo was great as after two weeks at the end of the eight weeks. Clinical trials enable these comparisons to be carried out to observe changes, strengths and the qualitative measure of effects of the therapy scientifically and unbiased. Validation of statistical tests of significance is guaranteed with randomized trials. The Chi-square test and the t-test can be justified alone without making further assumptions or distribution of variables.
Randomized controlled trials design allow for data to be capture and represented clearly for comparison. Data capturing software commonly used are EXCEL and SPSS. This software is used to maintain database for studies and keep track of any modifications and participant follow ups. Randomized controlled trials provide statistical evidence which can be used by this software and in turn allow for statistical analysis. This helps create a final report for and audience to read the important scientific findings. It also helps future therapists to be able to replicate the study at a later date.
Placebo in randomized controlled trials when supported by sound methodological consideration are justifiable. Trials with placebo used can be conducted with fewer patients as compared to trials with active ingredients being used. The trials with placebo group offer comparisons in which maximum treatment separation, the group that is exposed to the treatment and the group not exposed to the treatment. This increases the likelihood of detecting if the treatment works or could produce harmful side effects. Randomized controlled trial is the most accurate test of efficiency especially in pharmacotherapy trials with the use of placebos.
Researchers have argued that randomized controlled trials method favour biological treatments over psychological ones and it cannot assess the role that psychosocial factors like doctor-patient relationships. Wolf believe that the effects of placebos on his patients were dependent for the force on their conviction of the patient that this or that effect will result. Patients are convinced that a treatment works depending on the experience they encounter with their physician, the manner the physician suggests the treatment and the faith in or fear of the active agent itself.
The attitudes mentioned are relevant to psychotherapy and as such critiques scrutinise randomized trials on this aspect. In randomized controlled trials placebo effect is not always favourable and may result in adverse reactions or anxiety. Sometimes stopping the placebo will stop the counter reactions. Wolf and Pinsky reported of one patient who had overwhelming weakness, palpitation and nausea within 15 minutes of taking her tablets. Wolf and Pinksy found that placebos produced more improvement in subjective rather than objective manifestations of anxiety and tension but objective changes do occur.
It has been reported that placebo may reverse the action of pharmacotherapy. Wolf reported Tom, a human subject with a large gastric fistula, was repeatedly given Prostigmine which induced stomach cramps and diarrhoea. The same response occurred to tap water and lactose capsules and to atropine sulfate which usually has an inhibiting effect on gastric function. If the drop out of an experiment is high because of side effects the trial becomes ineffective as the sample will have been altered.
The results of randomized controlled trials are considered to not address if treatment will work on a particular patient. The experts argue that randomized trials are too generalised and as such cannot be applied to clinical and psychotherapy situations. A phenomena as diverse and complicated as psychotherapy as aspects are not equal and it is felt that no amount of clinical intervention or manipulation can alter this. Therapist, patients and their therapeutic interactions are not equal and this will not alter no matter how randomized or meticulous the selection of participants has been carried out.
Gold field and Wolfe, 1996, further discuss this and in assuming all things are equal randomized controlled trials risk studying an unfamiliar phenomenon that may not be practiced by therapists. Randomized controlled trials are generally considered to be more costly and time consuming. Analysis has to be made as to whether the intervention is developed enough to warrant an evaluation. This may prove difficult of the interventions that are dependant upon are skilled clinicians such as surgeons or psychotherapist. Some therapists are not willing to work in randomized trials and the search for therapists that will is time consuming.
Randomized trials need to be carried out for months or even years to come out with a good comparative result and this cost money. In some instances after months or years of study the trials may yield no results or no advantages over placebo. Time in randomized trials is required to assess the true effects of treatment as shown when a trail was carried out on mephenesin versus placebo. If the trial was carried out for longer information may have been obtained as to much longer the effect of placebo would have lasted. There are some concerns with ethical issues in relation to randomized controlled trials.
The use of placebo makes it possible for blinding in an experiment or controlled trial. Incomplete disclosure is used to accomplish results in an experiment and placebo is commonly used in this instance. The declaration of Helsinki demands that participants in a study be assured of the best diagnostic and therapeutic method even if in the control group(Rothman and Michels, 1994). The statement disagrees with the use of placebos as a control if a proven treatment exists. Failing to inform participants that they are receiving placebo raises some serious ethical issues.
There is also an ethical issue with the use of placebo if there is an effective treatment, the use of placebo will deprive an individual of treatment that they require. The use of placebo may answer the wrong question. If a new treatment has been tested and found to be worse or ineffective compared to the old treatment it may still be effective and better than no treatment or placebo. Randomized controlled trials are a powerful tool. Evidence for improvement under psychotherapy can be taken if the theory in which it is based is true and the efficiency of the technique used to investigate.
Random allocation and double blinding ensures that the views of the participants and therapists cannot bias the outcome of the assessment. The use of placebo needs to be examined with reference to the scientific relevance of the findings. All consideration needs to be taken into account of the medical and ethical implications of randomized controlled trials. Randomized controlled trials are the most commonly used and described by most experts as the most reliable form of scientific evidence.