Clinical trials vs anecdotal evidence




















Participants will be randomized into group 7 to be queried about their comfort with medication for treating their child's atopic dermatitis after hearing varying amounts of information about the treatment. Participants will be randomized into group 8 to be queried about their comfort with medication for treating their child's atopic dermatitis after hearing varying amounts of information about the treatment.

Outcome Measures. Primary Outcome Measures : Survey responses on "willingness to treat" [ Time Frame: 1 day ] Groups 1, 2, and 3 will be compared to assess whether caregivers are more willing to use a medication to manage their child's atopic dermatitis if presented with clinical trial evidence, anecdotal evidence, or both.

Groups 7 and 8 will be compared to assess how caregiver's willingness to treat with a doctor's recommended medication is impacted by the exclusion of anecdotal evidence, clinical trial evidence, or both. Eligibility Criteria. Information from the National Library of Medicine Choosing to participate in a study is an important personal decision.

Contacts and Locations. Information from the National Library of Medicine To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor. Please refer to this study by its ClinicalTrials. More Information. Perspect Psychol Sci.

Epub Feb 3. National Library of Medicine U. National Institutes of Health U. Department of Health and Human Services. The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Atopic Dermatitis. Study Type :. Actual Enrollment :. Actual Study Start Date :. Actual Primary Completion Date :. Actual Study Completion Date :. Group 1 Participants will be randomized into group 1 to be queried about their comfort with medication for treating their child's atopic dermatitis after hearing varying amounts of information about the treatment.

On the other hand I have come to seriously consider anecdotal stories. At this point I have hundreds of examples of people who have responded to alternative treatments for mental health. First I had to entertain that the early stories I became aware of might have validity. I did not immediately assume each and every story was conclusive of anything. But over time, scouring over websites, participating in email groups, reading countless books and then finally experiencing anecdotal relief myself, I can no longer deny that anecdotes are powerful evidence when accumulated en masse.

There are some alternative treatments that have been studied. Fish oil to treat mental anguish is now considered viable since there has been clinical trials. But the vast majority of alternatives have no studies. No one. You just have to try it yourself. Money is simply limited when it comes to studying extensively and then especially when it comes to marketing alternatives. Neither is done enough and it never will be as long as we as a society are beholden to traditional medicine.

This is true in all medicine, not just psychiatric medicine. And if we as a society were responsible about health care we would include serious scientific study of alternatives. I know responsible science would shed light on the truth of alternatives. Science, as practiced, however is beholden to pharma and capitalism.

I am a scientist and a survivor of mental illness. Of course I believe in math and studies that include a control. However, anecdotal evidence has its place.

It can lead to new treatments. Many of our well known drugs originated as folk cures—people noticed that certain plants took away pain. Today we use aspern which is found in many plants, especially willows. If one follows the research, all of our antidepressants do only slightly better than sugar pills. In some cases antidepressants do not do as good as a sugar pill—but these results are not published.

Much research that is good with a control has found that some things are as good as antidepresants—cognitive therapy and exercise for example. If we embrace the scientific method we should offer patients everything that has been found useful—not just pills.

Exercise, even if it is just as good, has many, many health benefits. This is called unplanned crossover. Ideally, analysis is performed on the basis of intent to treat: patients assigned to the surgical arm at randomization are analyzed as the surgical group although some patients did not get surgery , and patients randomized to medical arm are analyzed as the medical group although some patients had surgery.

Unplanned crossover study in a randomized study of Nissen fundoplication vs lansoprazole medical management. Analysis by treatment would analyze patients who underwent Nissen fundoplication vs patients who were treated with lansoprazole alone. However, intent-to-treat analysis would compare patients randomized to fundoplication all infants with light yellow onesies to patients randomized to lansoprazole only all infants with dark red onesies. The primary outcome variable is daily weight gain.

After 1 week, fortification is stopped in both groups for a week washout period so that carryover effects of one fortifier to the other group are avoided.

After 1 week of the washout period, group B is fortified with liquid fortifier, and group A is fortified with MCT oil crossover period. Weight gain is compared between groups A vs B and also within each group Figure 6. Planned crossover design. At the end of the week, outcome variable mean weight gain per day was measured and compared between the 2 groups. After a washout period of 1 week to avoid residual carryover effect, group A was fortified with MCT oil and group B was fortified with liquid human milk fortifier.

Within-group comparisons can be performed between 2 fortifications. Planned crossover studies are attractive and useful because they evaluate within-group and between-group comparisons Figure 6. Crossover design removes between-patient variation and requires fewer patients.

Order in which therapy is given may elicit psychological responses and difference in physiologic maturity with increasing postnatal age may influence response. Open-label study is a type of clinical trial in which the researchers and participants or parents know which treatment is being administered. This contrasts with single-blind and double-blind designs.

An open-label study may still be randomized. Strengths: A blinded trial is not possible in certain circumstances involving surgery abdominal drain vs laparotomy for NEC or intestinal perforation or physical intervention optimizing cooling trial for hypoxic ischemic encephalopathy [randomization to Limitations: A blinded trial is regarded as being less subject to bias than an open trial because it minimizes the effect of knowledge of treatment allocation on reporting of outcomes.

If the hypothesis was formulated after the data were analyzed, it is known as a post hoc hypothesis. Because spurious associations may be present just by chance, post hoc analysis should only be hypothesis generating and should be tested in future trials to confirm the effect seen. Strengths: A clinically relevant association may be detected during post hoc analysis. In a study evaluating inhaled nitric oxide in pulmonary hypertension, a finding associating respiratory alkalosis with later-onset sensorineural deafness may be detected by post hoc analysis.

As noted above, however, this hypothesis ideally should be tested in a future trial before an association can be confirmed. However, such a trial may not be ethically appropriate. Limitations: In addition to caution regarding interpretation of a finding on post hoc analysis, if the number of analyses increases, some positive results may be due to chance. The risk of erroneous conclusion increases with post hoc analysis.

Subgroup analyses are defined as comparisons between randomized groups in a subset of the trial cohort. The main reason for performing these analyses is to discover effect modification interaction in subgroups, for example, whether inhaled nitric oxide is more effective in reducing the incidence of death or BPD in preterm infants with birth weights greater than 1, g compared with infants with birth weights of 1, g or less.

To preserve the value of randomization, subgroups should be defined by measurements that were made before randomization. The subgroup effect should be one of a small number of hypotheses tested. If a large number of hypotheses are tested, some of the statistically significant findings may be due to chance alone. To discover whether the effect of treatment is different based on sex, gestational age, or birth weight.

Being smaller than the entire trial population, there may not be sufficient power to find important differences. A systematic review is the assembly, critical appraisal, and synthesis of all relevant studies addressing a clearly formulated clinical question and incorporating strategies to minimize bias. A comprehensive search of the literature is performed to identify, select, and critically evaluate all relevant research using systematic and explicit methods and to collect and analyze data from all relevant studies included in the review.

Statistical methods meta-analysis may or may not be used to combine the data in the included studies. Systematic reviews are retrospective analyses and, similar to other retrospective research, are subject to bias.

To limit bias, the clinical question should be clearly stated and explicit and systematic methods that can be reproduced by others should be used throughout the process.

The inclusion and exclusion criteria for the search and selection of studies, the subgroup analyses planned including the anticipated direction of subgroup effect , and sensitivity analyses planned should all be specified a priori.

The purpose of a systematic review: Systematic reviews summarize the available evidence relating to a specific clinical question. In addition to providing an overall estimate of treatment effect to guide clinical decisions, systematic reviews can also help to inform research by identifying the areas of uncertainty requiring further study and guide policy decisions based on the entire body of evidence. Advantages of adding a meta-analysis to a systematic review and interpreting the results of a meta-analysis.

A meta-analysis is a statistical method to pool effect estimates of individual studies and provide an overall estimate of treatment effect. The results of a meta-analysis are presented in a forest plot Figure 7. The forest plot has a horizontal scale that displays the possible values of treatment effect. If the effect estimate is a ratio eg, odds ratio or risk ratio , the scale is logarithmic.

Alternatively, if the effect size is presented as a difference eg, risk difference or difference in means , the scale is linear. On the logarithmic scale, the value of 1 lies on the line of no effect, whereas on the linear scale, the value of 0 lies on the line of no effect.

The vertical line in a forest plot is called the line of no effect, and if the confidence interval CI crosses this line, it indicates no difference in outcomes in the treatment and comparator arms.

Characteristics of a forest plot. This plot can be shown on a logarithmic scale when the line of no effect is at 1 or on a linear scale when the line of no effect is at 0. The squares represent individual treatment effects, and the diamond represents pooled effect. If the diamond crosses the line of no effect, the meta-analysis does not significantly favor experimental or control group. On a forest plot, the treatment effect of each individual study is represented by a square.

The point at the center of the square is the point estimate. The relative weight given to each study is represented by the size of the square usually determined by the study size , the CI is represented by a horizontal line that runs through the center of the block.

The pooled effect estimate is represented by a diamond at the end of all individual study estimates. The point estimate of the pooled effect is at the center of the diamond, and the CI is represented by the width of the diamond. If the diamond crosses the line of no effect, this indicates that after combining all relevant studies, there is no significant difference in effect in the treatment vs comparator.

It is not always appropriate to pool results of individual studies in a meta-analysis. Data from different studies can be combined when the studies address a common question and measure and report outcomes similarly. Alternatively, if the studies are very dissimilar or if the studies are at a high risk of bias, leading to a low confidence in the estimate of effect, the data should not be statistically pooled. The advantages of adding a meta-analysis to a systematic review can be summarized in the following points:.

The combination provides a pooled quantitative estimate of the effects of the intervention, and the uncertainty associated with the result can be inferred using the CI. Combining studies results in greater power to detect treatment effects and decreases uncertainty narrower CI and greater precision. The differences in included studies can be analyzed to explore differences in treatment effect in different study populations and settings.

The comparison of different studies may lead to new ideas and hypotheses for future trials. Because a systematic review is a retrospective review, similar to other retrospective studies, it is at risk of bias.

Use of explicit criteria and critical appraisal of the literature reduce the likelihood of a biased review. Not recognizing publication bias and bias in the conduct of the studies included in the review may lead to unreliable results. A thorough evaluation of the risk of bias of included studies and assessment of publication bias will limit this possibility. Publication bias is a distortion of the published literature that occurs when published studies are not representative of all studies that have been performed.

This bias is secondary to a tendency to submit and publish positive results more often than negative results. Careful consideration should be given to the studies that are included in the meta-analysis. The results are a direct reflection of the studies included in the analysis.

If the studies included are at a high risk of bias, and the results of the individual studies do not represent the true effect, combining these studies may result in increased precision of the wrong results, giving biased results credibility garbage in, garbage out. Analyzing the data by different statistical methods may give different results with the same set of studies. Heterogeneity should be considered and explored in the results of the meta-analysis.

The second part of this review covers bias and confounding, causation, incidence and prevalence, screening, sensitivity analysis, and measurement and will appear in a subsequent issue of Neoreviews.

National Center for Biotechnology Information , U. Author manuscript; available in PMC Dec 1. Author information Copyright and License information Disclaimer. Copyright notice. The publisher's final edited version of this article is available at Neoreviews. See other articles in PMC that cite the published article.



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