mteb/BrightProPsychologyRetrieval huggingface dataset:
This was a meta-epidemiological study, a study design used to compare
intervention effect estimates between trials with and without a characteristic
of interest [  12  ]. In this study, we focused on the
setting, with the aim of comparing PC-RCTs to ST-RCTs. A meta-epidemiological
study is performed by generally using a two-step approach and, contrary to
traditional epidemiological studies, units of analysis are studies rather than
patients [  13 :S1.") ]. First, for each
selected MA, we assessed the difference in intervention effects between
studies with the characteristics of interest (i.e., primary care setting) and
without the characteristics of interest. This step involved using a meta-
regression for each selected MA (with the intervention effect considered the
outcome and the characteristic of interest the independent variable). Second,
results from the meta-regression were meta-analysed over the different MAs.
*  Parallel-group  – each participant is randomly assigned to a group, and all the participants in the group receive (or do not receive) an intervention.  [39]  [40]
*  Crossover  – over time, each participant receives (or does not receive) an intervention in a random sequence.  [41]  [42]
*  Cluster  – pre-existing groups of participants (e.g., villages, schools) are randomly selected to receive (or not receive) an intervention.  [43]  [44]
*  Factorial  – each participant is randomly assigned to a group that receives a particular combination of interventions or non-interventions (e.g., group 1 receives vitamin X and vitamin Y, group 2 receives vitamin X and placebo Y, group 3 receives placebo X and vitamin Y, and group 4 receives placebo X and placebo Y).
---|---
 Association  |
*  Linear regression 
*  Ordinary least squares 
*  Bayesian
Main article:  Blinded experiment
*  Mean 
*  Arithmetic 
*  Arithmetic-Geometric 
*  Cubic 
*  Generalized/power 
*  Geometric 
*  Harmonic 
*  Heronian 
*  Heinz 
*  Lehmer 
*  Median 
*  Mode  "Mode \(statistics\)")
Q: You mentioned MultiLevel Models as a specific type of mixed model, how
would the use of MLM differ to whats been performed here?

It would be performed exactly the same way. We would describe it differently
though.

For example, we’d talk about the County  level
 (level 2) and the Observation level (level 1).
The outcome, number of jobs (n thousands), would be measured at the
Observation level. In other words, we have one measurement per county in each
decade.

Rural seems like it’s measured at the County level, but it’s not. That’s
because some counties switch from being rural to urban over the course of the
study.

Decade is measured at the Measurement level.
Related Posts

*  Specifying Fixed and Random Factors in Mixed Models 
* [ Confusing Statistical Term
*  Diffusion of innovations 
*  Health belief model 
*  Health communication 
*  Health psychology 
*  Positive deviance 
*  PRECEDE–PROCEED model 
*  Social cognitive theory 
*  Social norms approach 
*  Theory of planned behavior 
*  Transtheoretical model
https://doi.org/10.1016/j.respe.2017.09.004
This is a  hyperlinked text  in a blog post.
* Accepted  :  05 December 2022
* Subjectively assessed (e.g., pain)
16. Cochrane Bias Methods Group Cochrane Statistical Methods Group, Higgins Julian PT, Altman Douglas G, Gøtzsche Peter C, Peter J, David M, et al. The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials. BMJ. 2011;343:889–93.  https://doi.org/10.1136/bmj.d5928  .
###  Allocation concealment
Observational studies  |
**_30 Ways to Say “No” to an MLM Pitch_ **
Dependence 
|
BMC Medical Research Methodology
.") ], and they particularly express concerns about the applicability of clinical trial results used to establish guidelines to their own patients [  5 :359–63.
https://doi.org/10.1093/fampra/18.4.359
Shape  |
*  Contingency table 
*  Frequency distribution 
*  Grouped data
*  Health education 
* Higher education
*  Bachelor of Science in Public Health 
*  Doctor of Public Health 
*  Professional degrees of public health 
*  Schools of public health
20. Page MJ, Shamseer L, Altman DG, et al. Epidemiology and reporting characteristics of systematic reviews of biomedical research: a cross-sectional study. PLoS Med. 2016;13:e1002028.  https://doi.org/10.1371/journal.pmed.1002028  .
10: Mixed and Multilevel Models ](https://www.theanalysisfactor.com/many-names-multilevel-models/)
*  The Difference Between Random Factors and Random Effects 
*  Mixed Models: Can you specify a predictor as both fixed and random?
*  Adaptive clinical trial 
*  Stochastic approximation 
*  Up-and-down designs
* General enquiries:  journalsubmissions@springernature.com
*  Meta-epidemiological study 
*  Cochrane systematic review 
*  Primary care
*  Kaplan–Meier estimator (product limit) 
*  Proportional hazards models 
*  Accelerated failure time (AFT) model 
*  First hitting time
**Table 2 Characteristics of the included trials**
Written By  Brittany Morgon
*  Partial correlation 
*  Pearson product-moment correlation 
*  Rank correlation 
*  Kendall's τ 
*  Spearman's ρ 
*  Scatter plot
The terms "RCT" and "randomized trial" are sometimes used synonymously, but
the latter term omits mention of controls and can therefore describe studies
that compare multiple treatment groups with each other in the absence of a
control group.  [7]  Similarly, the  initialism  is sometimes expanded as "randomized clinical trial" or
"randomized comparative trial", leading to ambiguity in the  scientific
literature  .  [8]  [9]
Not all RCTs are randomized _controlled_ trials (and some of them could never
be, as in cases where controls would be impractical or unethical to use). The
term randomized controlled clinical trial is an alternative term used in
clinical research;  [10]  however, RCTs are also employed in other research
areas, including  many of the social sciences  .
Adeline Hoang & Clarisse Dibao-Dina
Risk difference  ,  Number needed
to treat  ,  Number
needed to harm  ,  Risk
ratio  ,  Relative risk reduction
 ,  Odds ratio
 ,  Hazard ratio
Clinical research  and 
experimental design
Although subjects almost always provide  informed consent
 for their participation in an
RCT, studies since 1982 have documented that RCT subjects may believe that
they are certain to receive treatment that is best for them personally; that
is, they do not understand the difference between research and treatment.
[31]  [32]  Further research is necessary to determine the prevalence of and
ways to address this "  therapeutic misconception
 ".  [32]
Some standard methods of ensuring allocation concealment include sequentially
numbered, opaque, sealed envelopes (SNOSE); sequentially numbered containers;
pharmacy controlled randomization; and central randomization.  [48]  It is
recommended that allocation concealment methods be included in an RCT's 
protocol  , and that
the allocation concealment methods should be reported in detail in a
publication of an RCT's results; however, a 2005 study determined that most
RCTs have unclear allocation concealment in their protocols, in their
publications, or both.  [57]  On the other hand, a 2008 study of 146  meta-
analyses  concluded that the results of
RCTs with inadequate or unclear allocation concealment tended to be biased
toward beneficial effects only if the RCTs' outcomes were  subjective
 as opposed to  objective
 "Objectivity \(philosophy\)") .  [58]
The first published Randomized Controlled Trial in medicine appeared in the
1948 paper entitled "  Streptomycin 
treatment of pulmonary  tuberculosis  ",
which described a  Medical Research Council
 "Medical Research Council \(UK\)")
investigation.  [20]  [21]  [22]  One of the authors of that paper was 
Austin Bradford Hill  ,
who is credited as having conceived the modern RCT.  [23]
Flowchart of the selection process
Testing hypotheses  |
Graphics  |
Observational study 
(  EBM II-2 to II-3  )  |
Trial/test types  |
An RCT in  clinical research 
typically compares a proposed new treatment against an existing  standard of
care  ;
these are then termed the 'experimental' and 'control' treatments,
respectively. When no such generally accepted treatment is available, a 
placebo  may be used in the control group so that
participants are  blinded  to
their treatment allocations. This blinding principle is ideally also extended
as much as possible to other parties including researchers, technicians, data
analysts, and evaluators. Effective blinding experimentally isolates the
physiological effects of treatments from various psychological sources of 
bias  .  [ _ citation needed
 _ ]
Other  |
---|---
 Regression analysis  |
|   Occurrence  |
*  Dickey–Fuller 
*  Johansen 
*  Q-statistic  (Ljung–Box)  
*  Durbin–Watson 
*  Breusch–Godfrey
Controlled experiments  |
*  Wikiquote
* Bland M (19 March 2008).  "Directory of randomisation software and services"  . _University of York_ .
* Evans I, Thornton H, Chalmers I (2010).  _Testing treatments: better research for better health care_  (PDF)  . London: Pinter & Martin.  ISBN  "ISBN \(identifier\)")  978-1-905177-35-6   . Archived from  the original  (PDF)  on 2010-12-25.
* Gelband H (1983).  _The impact of randomized clinical trials on health policy and medical practice: background paper_  (PDF)  . Washington, DC: U.S. Congress, Office of Technology Assessment. OTA-BP-H-22. Archived from  the original  (PDF)  on 2016-03-03.
*  "REFLECT (Reporting guidElines For randomized controLled trials for livEstoCk and food safeTy) Statement"  .
* Wathen JK, Cook JD (12 July 2006).  "Power and bias in adaptively randomized clinical trials"  (PDF)  . _M.D. Anderson Cancer Center, University of Texas_ .
###  Interpretation of statistical results
###  Transport science
---|---
 Engineering statistics  |
*  Exponential families 
*  Logistic  (Bernoulli)   /  Binomial  /  Poisson regressions
To balance group sizes in smaller RCTs, some form of  "restricted"
randomization  is
recommended.  [54]  The major types of restricted randomization used in RCTs
are:
*  Cohort study 
*  Cross-sectional study 
*  Natural experiment 
*  Quasi-experiment
In the early 20th century, randomized experiments appeared in agriculture, due
to  Jerzy Neyman  [18]  and  Ronald A.
Fisher  . Fisher's experimental
research and his writings popularized randomized experiments.  [19]
##  Blinding
https://doi.org/10.1002/jrsm.1392
*  Correlation 
*  Regression analysis
##  Conclusion
###  Meta-epidemiological analysis
And the causal mechanisms:
*  Biostatistics 
*  Child mortality 
*  Community health 
*  Epidemiology 
*  Global health 
*  Health impact assessment 
*  Health system 
*  Infant mortality 
*  Open-source healthcare software 
*  Multimorbidity 
*  Public health informatics 
*  Social determinants of health 
*  Commercial determinants of health 
*  Health equity 
*  Race and health 
*  Social medicine
*  Blocking  "Blocking \(statistics\)")
*  Factorial experiment 
*  Interaction  "Interaction \(statistics\)")
*  Random assignment 
* Randomized controlled trial
*  Randomized experiment 
*  Scientific control
respond)

Multilevel models and Mixed Models are generally the same thing. In our recent
webinar on the basics of mixed  models,  Random Intercept and
Random Slope Models  , we had a number of questions about
terminology that I’m going to answer here.

If you want to see the full recording of the webinar,  get it here
 . It’s free.
In 2004, the  International Committee of Medical Journal Editors
 (ICMJE) announced that all trials starting enrolment
after July 1, 2005, must be registered prior to consideration for publication
in one of the 12 member journals of the committee.  [34]  However, trial
registration may still occur late or not at all.  [35]  [36]  Medical journals
have been slow in adapting policies requiring mandatory clinical trial
registration as a prerequisite for publication.  [37]
---|---
 Hazard function  |
*  Selection bias 
*  Survivorship bias 
*  Correlation does not imply causation 
*  Null result 
*  Sex as a biological variable
* ** Optimal design  ** :  Bayesian 
*  Random assignment 
*  Randomization 
*  Restricted randomization 
*  Replication versus subsampling  "Replication \(statistics\)")
*  Sample size
|   Biostatistics  |
Like all statistical methods, RCTs are subject to both  type I ("false
positive") and type II ("false negative") statistical errors
 . Regarding
Type I errors, a typical RCT will use 0.05 (i.e., 1 in 20) as the probability
that the RCT will falsely find two equally effective treatments significantly
different.  [82]  Regarding Type II errors, despite the publication of a 1978
paper noting that the  sample sizes  of
many "negative" RCTs were too small to make definitive conclusions about the
negative results,  [83]  by 2005-2006 a sizeable proportion of RCTs still had
inaccurate or incompletely reported sample size calculations.  [84]
Spatial statistics  |
Some RCTs are fully or partly funded by the health care industry (e.g., the 
pharmaceutical industry  ) as opposed to government, nonprofit, or other sources. A
systematic review published in 2003 found four 1986–2002 articles comparing
industry-sponsored and nonindustry-sponsored RCTs, and in all the articles
there was a correlation of industry sponsorship and positive study outcome.
[102]  A 2004 study of 1999–2001 RCTs published in leading medical and
surgical journals determined that industry-funded RCTs "are more likely to be
associated with statistically significant pro-industry findings."  [103]
These results have been mirrored in trials in surgery, where although industry
funding did not affect the rate of trial discontinuation it was however
associated with a lower odds of publication for completed trials.  [104]  One
possible reason for the pro-industry results in industry-funded published RCTs
is  publication bias  .  [103]
Other authors have cited the differing goals of academic and industry
sponsored research as contributing to the difference. Commercial sponsors may
be more focused on performing trials of drugs that have already shown promise
in early stage trials, and on replicating previous positive results to fulfill
regulatory requirements for drug approval.  [105]
The Difference Between Random Factors and Random Effects

Random Intercept and Random Slope Models

Get started with the two building blocks of mixed models and see how
understanding them makes these tough models much clearer.

 Take Me to The Video!  

Tagged With:  fixed effect  ,  Fixed Factor  ,  hierarchical linear model
 ,  mixed
model  ,  multilevel
model  ,  panel
data  ,  random effect
 ,  Random Factor
##  Reciprocity
*  Analysis of variance (ANOVA, anova) 
*  Analysis of covariance 
*  Multivariate ANOVA 
*  Degrees of freedom  "Degrees of freedom \(statistics\)")
*  Compare means 
*  Multiple comparison
Retrieved from " 
https://en.wikipedia.org/w/index.php?title=Randomized_controlled_trial&oldid=1212831182

"
*  Clinical trial 
*  Trial protocols  "Protocol \(science\)")
*  Adaptive clinical trial 
*  Academic clinical trials 
*  Clinical study design 
*  Evidence-based medicine 
*  Real world evidence 
*  Patient and public involvement
* Trial type (PC-RCT or ST-RCT)
The number of treatment units (subjects or groups of subjects) assigned to
control and treatment groups, affects an RCT's reliability. If the effect of
the treatment is small, the number of treatment units in either group may be
insufficient for rejecting the null hypothesis in the respective  statistical
test 
. The failure to reject the  null hypothesis  would imply that the treatment shows no statistically significant
effect on the treated in a given test. But as the sample size increases, the
same RCT may be able to demonstrate a significant effect of the treatment,
even if this effect is small.  [59]
##  Definition and examples
Test  |
* If study designs are ranked by their potential for new discoveries, then  anecdotal evidence  would be at the top of the list, followed by observational studies, followed by RCTs.  [78]
* RCTs may be unnecessary for treatments that have dramatic and rapid effects relative to the expected stable or progressively worse natural course of the condition treated.  [79]  [80]  One example is  combination chemotherapy  including  cisplatin  for  metastatic   testicular cancer  , which increased the cure rate from 5% to 60% in a 1977 non-randomized study.  [80]  [81]
The _ CONSORT 2010 Statement
 _ is "an evidence-based, minimum set of recommendations for
reporting RCTs."  [70]  The CONSORT 2010 checklist contains 25 items (many
with sub-items) focusing on "individually randomised, two group, parallel
trials" which are the most common type of RCT.  [1]
A well-blinded RCT is considered the  gold standard
 "Gold standard \(test\)") for clinical trials.
Blinded RCTs are commonly used to test the  efficacy
 of medical  interventions
 and may additionally
provide information about adverse effects, such as  drug reactions
 . A randomized
controlled trial can provide compelling evidence that the study treatment
causes an effect on human health.  [6]
Time-series  |
Main article:  Sample size determination
####  Restricted
Rank statistics  |
####  Subgroup analyses
###  By hypothesis (superiority vs. noninferiority vs. equivalence)  ") ]
##  FOMO
###  Search strategy
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Completely
randomized  |
* All-cause mortality
You can also search for this author in   PubMed
  Google Scholar
* Type of primary care setting
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Categorical  / 
Multivariate  / 
Time-series  /  Survival analysis
A freebie or favor does not necessitate a debt.
* Number of included studies
---|---
 Survey methodology  |
|   Categorical  |
2. INSERM CIC1415, CHRU de Tours, Tours, France
*  Chi-squared 
*  _G_ -test 
*  Kolmogorov–Smirnov 
*  Anderson–Darling 
*  Lilliefors 
*  Jarque–Bera 
*  Normality  (Shapiro–Wilk)  
*  Likelihood-ratio test 
*  Model selection 
*  Cross validation  "Cross-validation \(statistics\)")
*  AIC 
*  BIC
Adaptive designs  |
Population impact  |
###  Relative importance and observational studies
[ Next  Next
* This page was last edited on 9 March 2024, at 19:41  (UTC)  .
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Partition of variance  |
* 2  Altmetric
5. Cranney M, Warren E, Barton S, et al. Why do GPs not implement evidence-based guidelines? A descriptive study Fam Pract. 2001;18(4):359–63.  https://doi.org/10.1093/fampra/18.4.359  .
*  Index of dispersion
18. Dechartres A, Trinquart L, Faber T, et al. Empirical evaluation of which trial characteristics are associated with treatment effect estimates. J Clin Epidemiol. 2016;77:24–37.  https://doi.org/10.1016/j.jclinepi.2016.04.005  .
Correspondence to  Amandine Dugard  .
---
General  |
15. Savović J, Jones HE, Altman DG, et al. Influence of reported study design characteristics on intervention effect estimates from randomized, controlled trials. Ann Intern Med. 2012;157:429–38.  https://doi.org/10.1002/sim.1184  .
MA: meta-analysis.
*  Drug development 
*  Hypothesis testing 
*  Impact evaluation 
*  Jadad scale 
*  Pipeline planning 
*  Patient and public involvement 
*  Observational study 
*  Blinded experiment 
*  Statistical inference
##  Supplementary Information
Time domain  |
An RCT may be blinded, (also called "masked") by "procedures that prevent
study participants, caregivers, or outcome assessors from knowing which
intervention was received."  [58]  Unlike allocation concealment, blinding is
sometimes inappropriate or impossible to perform in an RCT; for example, if an
RCT involves a treatment in which active participation of the patient is
necessary (e.g.,  physical therapy  ), participants cannot be blinded to the intervention.  [ _
citation needed   _ ]
##  Advantages
*  _Z_ -test  (normal)  
*  Student's _t_ -test 
*  _F_ -test
#  Randomized controlled trial
* Author
Controlled study 
(  EBM I to II-1  )
|
Main article:  Allocation concealment
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.") ]
* ** Random effect  **
*  Mixed model 
*  Hierarchical model:   Bayesian
* For  dichotomous  (binary) outcome data,  logistic regression  (e.g., to predict sustained virological response after receipt of  peginterferon alfa-2a  for  hepatitis C  [66]  ) and other methods can be used.
* For continuous outcome data,  analysis of covariance  (e.g., for changes in blood lipid levels after receipt of  atorvastatin  after  acute coronary syndrome  [67]  ) tests the effects of predictor variables.
* For time-to-event outcome data that may be  censored  "Censoring \(statistics\)") ,  survival analysis  (e.g.,  Kaplan–Meier estimators  and  Cox proportional hazards models  for time to  coronary heart disease  after receipt of  hormone replacement therapy in menopause  "Hormone replacement therapy \(menopause\)") [68]  ) is appropriate.
An analysis of the 616 RCTs indexed in  PubMed 
during December 2006 found that 78% were parallel-group trials, 16% were
crossover, 2% were split-body, 2% were cluster, and 2% were factorial.  [38]
##  Classifications
|   Correlation  |
History  |
1. Amandine Dugard
---
 Goodness of fit  |
2. Elsa Tavernier
##  Join the Conversation on Instagram
The first reported  clinical trial 
was conducted by  James Lind  in 1747 to
identify treatment for  scurvy  .  [11]  The first
blind experiment was conducted by the  French Royal Commission on Animal
Magnetism  in 1784 to investigate the claims of  mesmerism
 . An early essay advocating the
blinding of researchers came from  Claude Bernard  in the latter half of the 19th century.  [ _ vague
 _ ]  Bernard recommended
that the observer of an experiment should not have knowledge of the hypothesis
being tested. This suggestion contrasted starkly with the prevalent 
Enlightenment  -era
attitude that scientific observation can only be objectively valid when
undertaken by a well-educated, informed scientist.  [12]  The first study
recorded to have a blinded researcher was conducted in 1907 by  W. H. R.
Rivers  and H. N. Webber to
investigate the effects of caffeine.  [13]
Main article:  Pragmatic clinical trial
##  Wrapping it Up
Preventive healthcare 
|
###  Selection of relevant MAs and trials
Population health  |
Time:  2024/03/30 16:24:08
####  Sensitivity analyses
Specific tests  |
###  Ethics
_For each meta-analysis:_
34 languages
Mann HB  (1949). _Analysis and design of
experiments: Analysis of variance and analysis of variance designs_ . New
York, N. Y.: Dover Publications, Inc. pp. x+195.  MR
 "MR \(identifier\)")  0032177
 .