meta analysis vs systematic review

1. Systematic review vs meta-analysis | What’s the difference?
2. Systematic Review VS Meta-Analysis
3. Whats the Difference between a Literature Review, Systematic Review, and Meta-Analysis ?
4. Systematic Literature Review and Meta Analysis
5. What is the Difference Between a Systematic Review and a Meta-analysis?
6. Intro to Systematic Reviews & Meta-Analyses
7. 2. Systematic reviews and meta analysis

Systematic review vs meta-analysis | What’s the difference?

[Music],you may ask what is the difference,between a systematic review and a,meta-analysis,or is a systematic review the same as a,meta-analysis,in this video ill explain both of these,concepts,by using an example,well start with what is a systematic,review a researcher may study the,effectiveness of balance exercises after,an ankle sprain on the time it takes to,go back to football practice,the research team will analyze the,results by comparing the time taken to,return to practice between the group who,did the balance exercises and the group,who did no home exercises at all,and then theyll publish their findings,in an academic journal,this study is referred to as a primary,or empirical study,over time many researchers and research,groups generate new knowledge by,performing similar primary studies,worldwide,therefore,there may be more than one study that,investigate for example the,effectiveness of balance exercises after,an ankle sprain,these primary studies may be done on,different populations lets say some in,adolescent football players either,female football players maybe others in,hockey players,university students and so on,then one day a group of researchers with,a special interest in balance exercises,well come along and realize that there,are so many primary studies on the,effectiveness of balance exercises that,they decide to do a systematic review,the research group will then take all,these primary studies and using a very,systematic process to summarize the,findings into one research paper,they will put together a systematic,review,then lets get to what is a,meta-analysis,the research group who conducted the,systematic review may do a meta-analysis,as part of the systematic review,a meta-analysis is done by taking the,results from each of the primary studies,pooling these results together and,re-analyze them to look at the,effectiveness of balance exercises,across all studies,a meta-analysis cant always be done to,do a meta-analysis the primary studies,that,are being pulled together need to be,similar enough to one another,or in some cases the primary studies,consist of qualitative data where for,example interviews were done with,participants in which case no,statistical analysis can be done,let me know whether this explanation,makes sense to you by leaving a comment,in the comment box below this video,and also if you have any other questions,please ask and lets see how we can help,each other navigate this systematic,review journey together,how do you know whether youre dealing,with a systematic review or a systematic,review with a meta-analysis,youll often see the title of the,publication states whether its a,systematic review or a systematic review,and meta-analysis although it doesnt,always feature in the title so sometimes,youll have to read the abstract to,figure out that theres a statistical,analysis done if its not apparent from,the abstract you can scroll down to the,full paper,and have a look at the methods section,and the results section to see if a,statistical analysis were done,to summarize a systematic review refers,to the summary of primary studies into,one study using rigorous and systematic,methods while a meta-analysis refers to,the statistical analysis used to pull,all the findings from the different,primary studies into one analysis,not all systematic reviews include a,meta-analysis but all meta-analyses are,part of systematic reviews,if you have any questions around,systematic reviews see if you can find,the answer amongst the videos in the,systematic review playlist on the,research masterminds youtube channel or,feel free to ask a question by posting,it in the comment box below this video,see you on the other side of this,exciting systematic review journey,if you found this video helpful smash,the like button for more useful tips to,boost your research experience subscribe,to my channel by clicking the subscribe,button below this video,and while youre at it hit the bell so,that you get notified whenever i produce,a new video,if you need a solution to a challenge,not yet covered on my channel leave a,comment in the box below see you in the,next video

Systematic Review VS Meta-Analysis

el auto anda pasando a igual siguen with,us en 6 del gas del sistema de vida por,seis meses,[Música],systematic reviews words mcdonald s,works aquí está de frente terror sumen,students for learning for the first time,dirección field between the frames es,bonito acabar systematic review bolsas,vayan a voces indies ferial el fútbol de,diferentes sabores de clics de,diferentes nuestro fútbol benito antes,de anwar desde este mar y remember,systematic review y ser bíblico los,beckham sistemática admin es we can,previos lavables wars en salt and,publish papers son relectura y company,the weather sistemático y androide,primer guante verán de actor de 690,sistema de revue labora de manera no se,genera la sensación soy de aquí de sinn,fein sería sano bien final esta labor,desde el primer medio análisis es nada,se prestan disonante biberones mediana,veces están opcional componen el sistema,nervioso está estimado y bicameral se,les terminó pidiendo mediante la cesión,componen systematic review y es el,sistema de cribado que empezamos a mi,canal es el de metanálisis el actual,sistema de reviews bears va a dar al,sistema de virus que me comentan a veces,ya explicar de france berwyn son varios,los masters en saber igual es dentista,lo que no había requerido pista el otro,gato de nuestro esfuerzo es en tener un,cáncer del sistema de vives más terso,butters en manos del espíritu el primer,análisis exacto,normalmente los estudiantes de este,campo de conexión de antes de andar de,frente now when youre a del sistema,nervioso ryder y colectiveros from,previos la ifab las historias y un palo,press machac las reformas por sistema,nervioso en más tres masters por perforó,por de ítems por sistema de,matrículas,regresen mañana los estudios de,actualización visual para lópez maya,college and you que la vida a 40 pies,marcha que les han you by the paper de,áreas del sistema de nervios en mediana,bases es en extensión no les toca valdés,quake live sistema nervioso sistema de,viajar de facebook the last station,hasta planning state su plan el sistema,de revivir plan de orissa cuestión del,planeta para planear esta cuestión,javier incluyen excluyen bring your,shoulder de expresión definir el control,en ciudad planeta georges sistema de,radio station o facebook es radio en,yogur de facebook de esto se espera de,face new girl celeste aprender a veces,el centro nuevos,i,de fuld ex o antigua gran verdad en,remember duda han sido de han guardado,work el japón han extinguido el nuevo,rector colectivos de estar exterior que,han sido siete colegios testar is now,you,are,space for fighting tareas de actual,marcan a los space action se,distribuirán a las space y estos países,así que en facebook nada de todo face es,de mañana los space world,el wish book and the course ahora me dan,avances y es de game smart girls and the,matrix mago en efecto frax mar,remember,actual hijas del efecto de la federación,está sin efecto lo consideres de cruyff,también example acceder a esa medicación,yo estaré en adicionales de wright las,manos de muchos caminos de ambos líderes,tradicionales braille de llevar lo que,en arizona desde efecto en serio equipo,al tener acción en texto fragmento de,artes medicación de la décima efecto en,freising o persona en realidad por de,realidad es decir es normal decir red,world efectivo friend regular,diferenciación definitivo sólo basta de,frente en realidad soy enferma de la,ciudad y este es otro efecto sólo,ficción that we can you speak se,trasladó entonces usted está calmado el,debido proceso en el track btr texto,próximo en buenos deberías no desea que,la solución es fundamental,darwin medianoche,tú,efe,el,rector eladio frente en exteriores e,inversores el cantón y personal con,impresión esta desviación de los,ingresos hermoso las resolución de,fórmulas de oficio se renueve la,exmodelo efecto de su viuda de sainz,lewis moneyball y el aniversario del,team and highlights en el borde del,libro de flores para defender hoy en,haití han sido de ford explorer de,nexter pesos del fondo proyecta,publication más ansiado final para don,orione ex indudable wanda de la radio,céntrico de ganarla se están dando en el,labrit en guadix de qlikview danger,bendición a la ciudad como interesado en,estar y ser más en el club del estadio,workhen exterior sistemática and history,software similar a la de newton granados,es la distracción y la arena pública,main jugador de new que el número de los,lcd exteriores de millones de yenes,terios lugar mediante direcciones tareas,y estar y stock en evaluaciones en el,software antes que en el distrito de,mayor próximo la intervención antes en,el arauca media realmente francés en de,12 en 28 soles edición stories que nunca,mandé absolutely de akamai nivel soy es,del sistema de greg bagwell hard to be,cameron alces soy yo que nadie se escape,este es el género de los bailes este mar,y oliver inauguraban oportunidad,educación nuevas ganancias remember me,dan a la sesión componen el sistema de,gremio son el séptimo yo cambiado su,versión,historia,gueder combina entidades one wing,airlines cuando me raid vaya de esta vez,fue de us mayor producción de granadas,estamos viviendo,desde savona ganarlas está subiendo seis,equilibrios de diferentes remembering,systematic review de cambiar canales y,figuras similares tareas en google,plummer análisis by doing fix orden de,vedas martín exterior de frente al canal,con bailes y estamos teresa bernal,cambio estamos tenido activos,descontables el álbum problema semejante,valor problemas sexuales y gore por su,genio como en análisis tradicional con,by nivel no termina sistema y sobre,member of the stars y la combi nivel y,divulgó en the camera análisis y,despedida nada campaña del que no,guardar entonces en este medio,la situación es urgente diseñar como la,de nestares dice que ryan studies y,canadá como van der does white ball room,in a systematic review soy hubo la vía,express space one planet face del,desesperado beige de android en 2010,esas temática bíblica ciudad de roldán,star is different historias van y,convenimos tareas similares tareas nadie,sabe en el partido anterior sistema de,viento matinales explicación mayorista,opcional componen la meta navas es,generar como mínimo estar al aire libre,son de mera navajas de casas reverse gol,ácido es cuestión wyden ago amarán a la,sensualidad similares tareas a nivelar,el vicente calderón huerto escogerán,dudando guardia valores no artificiales,y si ya estoy desde la transición al,estadio del camp nou state street,station por facebook twitter o facebook,new haven ex profe destruida olvidado el,mañana bases baidu sándwiches ustedes,tricolor juniors en la ciudad de new,bilingüe de andar volvió maternal se,nombran a veces que inviten manuel willy,dejando el software igualmente pidió,work software de la mosca view manager,realmente son hablamos con él,como persona los problemas en el sistema,de preview y donny grant a las sesiones,el distrito de canales es,extranjero y está en análisis vaya,software sistema de gráfica en cualquier,sistema de gravilla escolar eide view,the sky werner desamor y en devolver el,primer barco de momento similares tareas,bolt inyectó manera de protesta mente,frente factible en realidades muy,diferentes en desventaja de los meses,número a word se ha contado con varios,frentes temarios bicamerales estoy este,astro servir ganan bien desamor y es,este medio vividos en mediana los es,hora de diferentes actividades no te,ofrece becas es tema de virus vuelve con,más ganancias y fijados similares tareas,del sistema de google no terminen,colectivos no termine de google la,rubiana bases se desgrana basados en el,software de google,mañana,de matemáticas historia de las mayores,en ciudad del este,cuesta de san vicente calderón a las,donde administra con banderas del sol de,estadísticas mar análisis de actualidad,público,este plan y guardias como en esta,historia de river hay de angers sombrío,el resultado el bayern jörg tengan,hambre si eres cuenta y te vas

More: clickbank review

Whats the Difference between a Literature Review, Systematic Review, and Meta-Analysis ?

hello my name is evan orlieb and welcome,to another edition of,education for today were going to be,looking at the differences,in the nuances associated with,literature reviews,systematic reviews and meta-analyses so,lets go ahead and get started,first lets try to define what is a,literature review we know that,often times in undergrad or graduate,school or even our perf,in our profession were oftentimes asked,to do a literature,literature review see whats out there,and essentially it requires that you,synthesize a variety of sources,of different subtopics to come to a,greater understanding,of the state and not of knowledge on a,larger issue so lets say that youre,trying to look at,uh uh teacher retention or youre trying,to look at,um uh you know what are the struggles,that that,eighth graders have in mathematics or,whatever the topic might be cancer,treatment et cetera,youre going to oftentimes conduct a,literature review,to see what does the extant literature,what out there,already exists that has been researched,that we can learn from that,in order to identify the gap that may,exist within,that extant literature essentially it,works,like a jigsaw puzzle where you can,arrange,a literature review oftentimes based on,a topic,or a theme in particular and together,these individual pieces,have to be put together in order to,reveal a greater sum,and at the bottom of this page is its,its very important to note,that a literature view is not the same,thing as,a bibliographic reference list which is,where you,take lets say five or ten different,studies and you write a paragraph on,each of those,thats not a synthesis thats simply,recording,a a list of bibliographic references,and sort of putting in an abstract or a,summarization,of what is each of those articles a,literature review is very different,its a synthesis its putting all of,that together,these three articles talked about such,and such these other ones talked about,this other sub theme,and then trying to put those together to,really cover,uh what youre looking on doing uh,within this,literature review the next slide talks,about uh,what are the sources that we want to,primarily use,for our literature reviews of course the,most respected ones,are those that are peer reviewed,oftentimes in scholarly journals,so thats articles in these journals,textbooks come,far later down the road we often,uh have a habit of over,quoting if you will instead of using our,own words to guide the literature review,in our write-up of that uh we oftentimes,uh overly rely upon other peoples words,so,think about the synthesis oftentimes has,a paraphrases rather than direct quotes,the other ones that are okay to use in,moderation,include white papers conference,proceedings from,from conferences and other sort of think,tanks,other ones that you might want to just,use on a rare occasion,are news sources bbc washington post etc,and then other ones to avoid altogether,as it says here,uh wikipedia and other websites from,predatory journals are ones that cant,necessarily be,confirmed for being valid and or,reliable,when we go into a systematic review what,what,constitutes that and how is it different,from a literature review a systematic,review,essentially is one thats on a,particular topic,its been systematically identified,appraised and summarized,and so lets say that your topic is,school choice and you wanted to conduct,a systematic review of that,here are some things that we want to,further consider,within this so a systematic review as we,said,already is different from a literature,review in that,um it it is sort of,is a subset of what a literature review,exists and so were going to talk about,what are the criteria,that you might use to conduct a,systematic review and how is it further,unique from that literature review and,then were also going to dovetail that,into a discussion,on the differences between a systematic,review,and a meta analysis so in,the systematic review is an overview of,primary research studies using an,explicit,and reproducible methodology so its not,just,you google search and these are the,first 10 that popped up,it could be lets say that youre,looking at reading fluency,it could be all the reading fluency,studies that were conducted in the last,10 years,it could be all those that use case case,study methods only,so whatever it could be on fluency,issues between,kindergarten and second grade so,whatever those criteria are that you use,and you dont have to just use one of,those it could be a combination of,multiple ones,thats the methodology for your,systematic review,of the extant literature and so this is,a rigorous method,uh summarizing what ex what research,already exists and it will oftentimes,show what we know and what we dont yet,know,on that topic and as it says in red on,the bottom literature reviews,dont always use that criteria as a lens,for including studies within a,literature review but in a systematic,review,we definitely do,further systematic reviews uh the aim of,it is to find,all the relevant research studies,published and unpublished,within that criteria where i said grade,levels or,time periods or what have you and youre,trying to assess,the overall um assess each study to the,overall criteria as i mentioned before a,date range methods used etc,synthesizing those findings in an,unbiased way and presenting a balanced,impartial summary of all of that,together including the flaws and,limitations of each of those studies,the advantages of a systematic review,over a literature review,including summarizing evidence keeping,people up to date on the latest,uh research findings allowing a large,amount of data to be presented and,assimilated in a smaller way,a clear picture if you will and in a,sense,in doing all of that youre reducing the,bias that is included within this,systematic review,as opposed to just a smorgasbord array,of studies included within a literature,review,those explicit methods that are included,are going to allow you to hone that,focus,and as a result you will also have more,reliable,conclusions because of that,if were looking at the type of design,research design that is included within,studies that that you want to use within,your,systematic review for instance these are,the ones in terms of ones that are more,rigorous,in nature and more reputable overall,so as we talked about before it depends,upon your field of study,as to whether or not truly experimental,studies can be done,oftentimes in my field education youre,going to be looking at,a non-randomized quasi-experimental,control,and experimental groups,a meta analysis again uh,is is again were looking at so we went,from literature review,to systematic review to a meta-analysis,and a meta-analysis,is the process of using statistical,methods to combine,different studies in order to come up,with a new finding,so the aim is to integrate all those,findings pull the data,and identify trends overall so some of,the benefits of that,which is more of an advanced approach,than i would say the other two were,somewhat more fundamental or,foundational in nature,youre going to aggregate that,information to lead to a higher,statistical power,in order to derive more uh,greater credibility with your overall,study,also the investigator has to make,certain choices,including deciding how to search for the,studies,selecting studies based upon a set,objective criteria,how to deal with incomplete data which,is oftentimes difficult,analyzing the data and accounting for,which ones you included and also,potential biases along the way,and as a result youre going to be,making a lot of judgment calls,within this overall process and thats,going to affect your results,here is one example of a meta-analysis,done in my particular field literacy,education,uh just a little bit ago from some,colleagues over at george mason and what,they did is,they were curious what sort of topics,what sort of methods what sort of,theoretical frameworks are,are most popular

More: body fortress whey protein review

Systematic Literature Review and Meta Analysis

if youre planning to do or perhaps just,even read and understand systematic,literature review and meta-analysis,your starting point has to be that,youve got a clear understanding of,exactly what is being done and thats,what were going to deal with in this,video,if youre doing a systematic lit review,youre doing three things right firstly,youll identify relevant research that,focuses on a very specific question,now that research has to be selected,based on pre-specified eligibility,criteria and were going to talk more,about the importance of systematic,literary view being replicatable later,on in this video,secondly youre going to appraise the,research and that means that you can,look at both the quality of the studies,performed and at the strength of the,evidence in the papers that you find and,finally youre going to synthesize your,findings so that you can draw some kind,of conclusion right this is often but,not always done using meta-analysis,right and were going to talk more about,meta-analysis in just a minute so stay,tuned,now its important to note that if you,do a systematic literal because youre,trying to answer a question you are in,fact undertaking a kind of research so,your methods must be clearly stated,youve got to describe how you,identified how you appraised how you,synthesize the studies so that your work,can be replicated and sometimes even,repeated as additional evidence gets,added to the body of literature over,time,now you have to start by clearly,defining the question that youre trying,to answer and its quite common to use,the mnemonic pico as a framework now,pico stands for p patient or problem or,population i intervention right c,comparison or control and o outcomes and,its by defining these aspects of your,research question very clearly it,becomes possible for you to get going on,your literature search strategy,a super quick interruption to this video,to say thanks to nested knowledge nested,knowledge sponsored this channel and i,absolutely love them nasas knowledge is,an online platform that you can use to,do literature review and systematic lit,review and what i love about this,platform is that im using it for the,entire process beginning to end all the,way from search screening tagging,extraction all the way through to,actually writing the manuscript creating,a living document online ive got my,entire team using it so we collaborate,different people doing different parts,of the process i used to hate litterview,now i love it if you want to love lit,review check out nested knowledge click,on the link in the description below and,without further ado on with the video so,lets talk about your search strategy,one of the biggest challenges that,youre going to face when doing a,literature search is that youre going,to find too many papers,so you need predefined inclusion and,exclusion criteria this might include,limiting the search to only those that,contain certain types of studies like a,randomized control trial for example or,limiting the search to include only,studies that were published in a certain,time frame like over the last 10 years,for example these limitations are fine,provided that you can provide a,rationale for them and that you define,them ahead of doing the search itself,now lets talk about appraising the,studies or the appraisal of the studies,the quality and the strength of each,study must be appraised this includes,both the size of the study but also the,type of study performed so a randomized,control trial provides stronger evidence,than a cohort study which provides,stronger evidence than a case control,study for example look for things like,whether or not the study protocol was,registered before the study was,undertaken registering a study is an,excellent way to protect against p,hacking now p hacking is a process,whereby researchers will consciously or,unconsciously adjust their research,methods as they go along to nudge the,study results in a certain direction so,as to draw a certain desired conclusion,and finally lets talk about the,synthesis,the evidence is extracted and,synthesized and this could be,quantitative right pooling of the,results using a meta-analysis or it,might be a narrative synthesis which is,sort of more qualitative and often its,a combination of both,so lets talk about meta-analysis this,is the most common form of synthesis,meta-analysis is a statistical technique,for quantitatively pooling results of,individual studies the results are,usually presented in a forest plot okay,and im going to talk you through how to,interpret a forest plot in just a minute,so stay tuned and importantly studies,can only be combined in this way if,theyre sufficiently similar in other,words if studies are too heterogeneous,right theyre too different from each,other then it doesnt make sense to pool,results,heterogeneity can result from number one,differences in the population being,considered number two differences in the,intervention being considered number,three differences in the outcome being,measured number four methodological,differences and number five chance now,lets take a look at the elements,included within a meta-analysis first we,have the names of the trials of course,then for each trial weve got the trial,results again its usually an odds ratio,and the size of the square indicates the,relative size of the study here we have,the 95 confidence limits around the,individual trial results and of course,weve got the weight that each trial,contributes to the overall pooled,results then weve got the pooled,results thats if meta-analysis is done,and its not always done and the points,of the diamond indicate the 95 percent,confidence interval here weve got the,significance of the pooled results,and here weve got test for,heterogeneity in other words if the p,value is less than 0.05 this indicates,significant heterogeneity between the,studies thanks for watching this video i,hope you found it useful stay and watch,another video and hit the like button if,you enjoyed it write a comment below,ill try and respond if i can dont ever,change dont do drugs always do your,best to speak to you soon

What is the Difference Between a Systematic Review and a Meta-analysis?

whats the difference between a,systematic review and a meta-analysis,stick around and find out today on this,episode of navigating academia,[Music],whats up everybody my name is dr. J,Phoenix Singh and I want to warmly,welcome you to this episode of,navigating academia your leading source,for guidance on how to advance your,career in academia before we get started,you know I appreciate the love so please,take a moment to like this video share,it with your friends with your,colleagues with your students and be,sure to comment below we always love to,hear from you especially if you have,recommendations for future episodes you,can also follow us on these social media,accounts so youve decided to get into,the field of reviewing now this is an,incredibly important area when it comes,to scientific research because,eventually in any field you have so many,primary studies that they literally,almost can be perceived as individual,trees but you can spend so much time,looking at these trees that you,literally forget to see the forest,itself its so important to be able to,zoom out and see that 10,000 foot view,every now and again and thats what the,field of reviewing does now theres,three main kinds of reviews we have,narrative reviews systematic reviews and,meta-analyses and my goal today is to be,able to distinguish them for you,narrative reviews first the thing about,a narrative review is that basically you,can use it as a soapbox to be able to,say whatever you want for example some,people are very anti vaccination for,example regardless of the tremendous,amount of peer-reviewed research,literature suggesting that there is no,harm that comes from vaccination you,still have some research very few pieces,but a few pieces that suggest that there,could be some issues there if you want,to do a narrative review you could just,disregard the preponderance of,scientific research and write an entire,piece talking about you know the the,potential harms of vaccination you could,put that in there right and if you,wanted to you could make the whole,article on that without even mentioning,everything else so it can serve as,almost a political soapbox and of course,you could also do it the other way you,could basically get on the soapbox and,talk about everybody needs to be,vaccinated and never mention there that,there is any kind of counter arguments,that people talk about in the field as,well you can do either,we see this all the time with stuff like,climate change and a variety of other,kind of politically contentious issues,where the research literature is,relatively clear so that is a narrative,review at the end of the day were not,specifically going through the,literature to be able to kind of have a,systematic review of anything were just,doing it to be able to give you a,general sense of me the author or the,authorship teams opinion essentially on,a given area second weve got a,systematic review now a systematic,review is really where we start to,inject really just a concept of science,into the reviewing process and really,its going to take a few key steps to,get a systematic review done the first,step is conducting whats called a,systematic search the idea here is that,youre going to go on to a database a,search database like a Google Scholar,and Eric a cinahl and EMBASE pubmed,right there are so many of these things,and depending on the field that youre,in youre going to be able to find ones,that really have or focus on your fields,literature because theres so many tens,of thousands of journals out there no,single search engine can really do a,great job and really drilling down for,for every single field together right so,find the one that really has the bit,that is gonna be the best fit for you,once youve got it come up with a list,of search terms these are going to be,terms that you can either use one by one,or you can combine them using what are,called boolean operators if you dont,know how to spell boolean its Bo o el,eam and what youre going to do is,essentially use these operators words,like or and the use of parentheses the,use of quotes theres so many ways to be,able to do this to systematically search,the entire literature for articles that,meet your pre specified inclusion,criteria now you got to come up with,inclusion criteria and these could be,things like publication status maybe you,want to include everything maybe you,want to say no conference presentations,no government-wide papers I only want,things that have been published in,peer-reviewed journals already and,within a certain date range maybe only,between 2000 until the present year made,you could be something where you only,want studies published in Europe maybe,you only want studies where the sample,is comprised a hundred percent of women,whatever it is you get to pick but make,sure that in your methods section when,youre writing it up youre really clear,about the terms that you search the,limits that you said all this kind of,stuff right what search databases did,you search you got to be really,transparent such that somebody else,could come use the identical methodology,and get the exact same findings,this is science right its got to be,reproducible its critical so that is,the systematic search now when youre,done you got to get your hands on these,articles and this could take a long time,but once youve got the different pieces,you got to read everything usually,youre gonna come up with a coding sheet,in terms of information you want to,extract maybe you want to extract things,like lets say that youre taking a look,at the efficacy of a drug lets say,youre in big pharma right and youre,doing a review on lets say the efficacy,of zoloft right and the the effect size,that youre going to take out of every,single study is something called Cohens,D right which is a measure of efficacy,right of an intervention so okay so out,of everything I can extract Cohens DS,to the extent possible right,as well as just demographic information,what percentage of the the of the sample,is male what is the average age what is,the diagnostic breakdown of people in,the sample were they in the community or,in an institution whatever theres so,many things you could pick apart and,usually you do that with some sort of a,coding sheet and then after you actually,have done that coding you should have a,secondary person come in and code like,recode a random sample of what youve,coded and then take a look at the,interrater reliability of the codings,using something like a Cohens CAPA and,intraclass correlation coefficient also,known as an ICC something like that to,be able to again scientifically prove,that youve extracted the data correctly,now when thats done though youre,basically done and what I mean by that,is that then you can do thumb attic,analyses you can read the papers look,for patterns in the data,but you,are not quantitatively synthesizing,youre not taking those individual,Cohens DS that youve collected and,wrapping them together to be able to get,kind of one summary Cohens D youre not,doing that okay this is the end of the,systematic review and systematic reviews,are great to be able to come up with,with both suggestions for future,research but also to be able to recap,whats already been done in a field,right so its more hypothesis-generating,than it is hypothesis testing as it were,now in terms of hypothesis testing youd,want to go on to the third approach and,the third approach is a meta-analysis,now think about it like this every,meta-analysis is a systematic review but,not every systematic review is a,meta-analysis okay now what does that,mean,well to do a meta-analysis you got to do,everything that I just said for a,systematic review the only difference is,that were going to use very advanced,statistical techniques and theres so,many kinds of meta-analysis tabular meta,analyses individual data analysis,Network meta-analysis theres so many of,these things but were going to use it,to be able to combine quantit

Intro to Systematic Reviews & Meta-Analyses

hi in this video were going to talk,about meta-analyses and systematic,reviews now systematic reviews sit atop,the evidence-based medicine,pyramid you can see here because they,represent the strongest form of evidence,that we have and the way these are,constructed is by taking individual,studies which we had looked at before,looking at individual studies and now,you take them all and you combine them,into one review now why would you want,to do systematic review what may perhaps,you have a complex issue that has many,different papers that are done on it you,want to look at all of them in one place,and come up with conclusions or perhaps,you want to increase the precision each,one of these papers may have a smaller,sample size and so it has it doesnt,have good precision meaning its,confidence intervals are huge and you,want to increase that so by taking a,bunch of them you can put them all,together and get a bigger pooled sample,size and increase the precision or,perhaps theres a lot of discrepancies,in the literature so maybe you have some,studies that are for a particular,therapy and others that are against it,and so you want to you want to take a,definitive look at all of them up come,up with a conclusion now theres,different ways that you can come up with,these overviews and the first one is,called a narrative review and in a,narrative review an author will take a,bunch of these papers theyll just pick,you know pick a bunch of them and,theyll read them review them and then,come up with their conclusions now these,are pretty good they look at a bunch of,different studies so its better than,looking at one paper but theres no real,process by which these are the papers,are selected so there could be bias in,there why did the author pick these,perhaps they pick the ones that were,only in line with what they were,thinking with their own conclusions and,so they pick things that supported their,conclusions these are often good for for,getting answers to background questions,and theyre good for a brief overview,but theyre not there theyre definitely,prone to bias now a systematic review,you dont just pick any articles you,have a system by which you pick them,thats why its called systematic you go,to the literature in a systematic way,and you get all the articles and so that,process exists and anyone who does that,process would get the same bunch of,articles then theres a systematic way,by which,you evaluate the individual articles in,a systematic way that you combine them,all into one and make your conclusions,now meta-analysis its a subset of,systematic reviews and these are the,ones where you would take the data from,each individual studies and then pull,them all together and then evaluate that,so before we look at how to evaluate a,systematic review lets look at how you,would do one itll itll make it make a,little bit more sense so lets say you,have an author here who has a particular,question about the literature now that,question needs to be formulated in a,nice tight and focused way and the best,way you want to define that question you,can use the Pico method right with,patients,the particular patients to find the,intervention the comparison and the,outcome we need to be sure that we are,asking a question that is focused you,cant ask in all treatments for mi does,it help right you need to know is it,different between cardiac Caths,versus TPA versus medical treatment but,you also dont want it to be too focused,like you cant see Im only looking at,47 year-old left-handed people who have,a heart attack it has to be,generalizable and so you want to have a,question that is not too broad but not,too focused and Goldilocks question the,other thing you also need to do is you,need to identify your inclusion and,exclusion criteria from the start so if,youre going to go to the literature we,need to know which articles were going,to look at are we going to include older,people maybe we dont want to look at,people who are 75 or older or dont want,to look at people who are 18 and younger,maybe we dont want to look at studies,outside of the United States maybe we,dont want to look at that we do want to,look at those but you need to decide on,that from the start,before you go searching the literature,because this is one way to avoid bias,now the next thing that were going to,do is were going to conduct a,literature search so Ive depicted the,literature here is this big cloud with a,bunch of papers in it theres a lot of,things that you need to look at and so,we want to look at as many of these,papers as possible and so where is the,place that most of us will go well,well go to PubMed and we will look at,MEDLINE and so thats the first place,that were going to look as redline but,our other databases that exist for,example EMBASE is the European version,of MEDLINE theres also a database of,systematic reviews by the Cochrane,Collaboration called the Cochrane,Library and thats another great place,to look but what about stuff that is not,in one of those databases how are you,going to find those perhaps you want to,look at something that are in the,smaller journals that has not included,in these catalogs or even unpublished,research maybe theres a study that had,no effect it showed it was a negative,study and those dont tend to get,published and so perhaps its just,sitting in the desk drawer of a,researcher somewhere and so wed like to,include that or maybe there are some,trials that are currently going on right,now and so they havent been published,yet or maybe there are abstracts that,have been presented at conferences,theres a lot more information that we,want to look at so you want to do a full,literature search you need to look at,all of these places but how are you,going to find these if theyre not,specified in here well the best thing we,can do is to ask an expert you know when,you get when you go to MEDLINE and you,find the one author whose name seems to,appear and on all the papers ask them do,you know of any other some other studies,that are done perhaps in a smaller,Journal or perhaps others that are not,published and they can help you find,more more of these studies you can also,look in the references of the articles,that you pulled and so that will help,broaden your your your list that youre,going to look at so now that youve,defined your database you also have to,also define your search terms that,youre going to look for and do your,literature search and then youre going,to go ahead and pull the articles so,after having supplied the search terms,you get a bunch of articles and you,first start by reading the abstracts and,applying the inclusion and the exclusion,criteria,perhaps we said were only going to look,at articles that took place in the,United States from the year 2004 word,and so one of them was from 1996 he,would get rid of that one theres,another one from 2003 but it was in,Canada maybe you want to get rid of that,one and so then you decide which ones,you want to keep,or not and so this person might say it,okay look I want to keep that one I,dont want to keep that one I want to,keep this one but how – how do we know,that this person wouldnt introduce bias,when they look at these well the trick,there is you want to have multiple,reviewers doing this so lets say this,person looks at the article and this,person looks at this article if they,both say keep it you keep it if they,both say get rid of it you get rid of it,but what if theres disagreement what if,one says keep and one says get rid of it,well then you have a third person thats,a tiebreaker who can decide whether or,not we need to keep that article so we,would pull the articles read the,abstract apply the inclusion and,exclusion criteria and then the next,step is to actually read the articles,now we go back and go into the other,ones that met the first pass now you,read them again and you decide which,ones continue to meet our inclusion and,exclusion criteria and again were going,to use the mu

2. Systematic reviews and meta analysis

welcome to the second video in this,series of critical appraisal modules in,this module we will be focusing on the,critical appraisal of systematic reviews,and meta-analysis using the critical,appraisal skills program or CASP,approach the learning outcomes for this,module aim to demonstrate to you the key,principles and stages of systematic,reviews so you will know broadly how,they are conducted and when we might,want to refer to this type of evidence,in decision-making we also want to get,you thinking about those critical,appraisal concepts relating to validity,trustworthiness of results and value and,relevance in the context of systematic,reviews and how they might be applied in,practice finally there will be a link to,a short quiz at the end of this video,which will give you the opportunity to,test your knowledge on concepts we will,have discussed using multiple-choice,questions and answers we will be making,reference to a recent Cochrane review,entitled inpatient vs. outpatient care,partial hospitalization and waiting list,for people with eating disorders by heya,Tao in the context of this training when,we talk about systematic reviews we will,be referring to those that,systematically summarize and analyze the,results from quantitative healthcare,studies namely randomized controlled,trials or RCTs these types of systematic,reviews can provide a high level of,evidence of effectiveness of healthcare,interventions and rely on meta analyzing,the results from several RCTs this is,done in order to obtain an overall,estimate of treatment effect across our,CTS that tests the same intervention on,similar participants and under similar,treatment conditions a common analogy is,that systematic reviews bring together,apples and oranges and that combining,these can yield a meaningless result,this is true if apples and oranges are,of intrinsic interest on their own but,may not be if they are used to,contribute to a wider question about,fruit for example a meta-analysis may,reasonably evaluate the average effect,of a class of drugs,by combining results from trials where,each evaluates the effect of a different,drug from the class systematic reviews,aim to present the best available,evidence in informing individual,patients and healthcare policies we can,also more reliably identify benefits and,harms of a particular intervention using,statistical methods to combine the,results of multiple RCTs in,meta-analysis this helps to add power,and reliability to findings because,there are now over 50,000 RT Ts,published per year systematic reviews,assist healthcare practitioners to keep,abreast with the continually increasing,number of publications reviews used as a,starting point for developing clinical,guidelines and they are also important,when researchers are considering,submitting applications for research,beds or ethical approval as they provide,justification and reinforcement of the,current state of the evidence in a given,healthcare field although they are,primarily concerned with the secondary,analysis of our CTS already undertaken,by other researchers systematic reviews,should follow a set protocol which,clearly set out the review question the,inclusion criteria for randomized,control trials and the data collection,process and procedure in an explicit and,transparent way by supplying this study,selection bias becomes less of a risk,this rigorous systematic process intends,that if a different research team were,to follow the same procedure they would,find the same studies and by using the,same systematic data analysis methods,they would ideally find the same results,as well although systematic reviews are,recognized as the strongest design in,identifying effects of interventions as,with all other research designs the,value of the review depends on what was,done what was found and the clarity of,the reporting reporting quality varies,and published research and systematic,reviews are not immune therefore it is,important to be able to be critical and,consider whether review authors have a,dear to their protocol,the steps of a systematic review are,typically as follows it includes,defining the question searching and,reviewing the literature sifting through,studies to select relevant ones,assessing the quality of the studies,calculating the outcome measure of each,study and combining them in meta,analysis if appropriate and interpreting,the results the CASP proach actually,follows this process in its item,checklist and asks us to consider where,the review authors have been transparent,and explicit in their planning execution,and delivery of their review youll,notice that the casper checklist breaks,down the three central principles of,critical appraisal into three sections,section a relates to validity section B,the trustworthiness of results and,section C focuses on value and relevance,or how the results would help locally so,well take a look at each step alongside,the checklist and the Cochrane review by,heya Tao the first question asks us to,consider whether the review authors have,been explicit and clear in their,inclusion criteria relating to the,population or participants of interest,the intervention given and comparator or,controlled condition and the outcomes,considered in shorthand this is known as,the Pico and helps systematic reviewers,to clarify and make explicit their,inclusion criteria when defining,participants what are the,characteristics of the patient,population and what is the condition or,disease the review authors are,interested in investigating when looking,at the intervention what is the,experimental drug treatment or exposure,of interests the review authors want to,measure the effects of including benefit,and harm and how is it defined,comparison what is the comparison or,control intervention that the review,authors want to measure against this may,include placebo sham treatment a,different drug or no treatment the,comparison should be a suitable measure,against the experimental treatment arm,and take into account the needs of the,participants and state of current,knowledge,finally what are the relevant outcomes,and how are the review authors defining,them as relevant how do they intend to,measure and analyze them in,meta-analysis some outcomes may be,measured differently between RCTs and it,is important to know how authors intend,to handle different data taking this,Pico format in the review by heya Tao we,can see that they have clearly defined,their participants as adults adolescents,and children with a diagnosis of acute,anorexia nervosa bulimia nervosa binge,eating disorder or specified or,unspecified eating disorder according to,specified criteria we can see that they,have defined their intervention as,inpatient care for either weight,restoration in Iraq SIA nervosa or,bulimia nervosa and other eating,disorders provided by a specialist,service for eating disorders and health,professionals they have provided a,longer list of comparator interventions,which have been detailed and described,as for their outcomes they pre specified,in their protocol that they would,include clinical improvement and,acceptability as their two primary,outcomes for anorexia bulimia and other,eating disorders they also detail their,secondary outcomes of interest of,clinical response recovery quality of,life depression scores general,psychiatric symptoms cost-effectiveness,and clinical improvement at one year,following the end of treatment the,authors have also clearly described how,each of these outcomes has been measured,its important to really familiarize,yourself with the Pico of a systematic,review before you start critical,appraisal in order to make sure that you,are clear about the definitions being,used by the review authors which may be,different definitions you are used to in,your own practice once the research,question and the Pico are clear you will,also want to familiarize yourself with,other criteria the review authors have,set in making sure they sele