J Dent Hyg Sci Vol.14, No.3, 2014, pp.269275 REVIEW ARTICLE Consolidated Standards of Reporting Trials 의소개 : 무작위대조군연구의보고지침 정회인 김희은 1 연세대학교치과대학예방치과학교실, 1 가천대학교보건과학대학치위생학과 Consolidated Standards of Reporting Trials: The Reporting Guideline for Randomized Controlled Trials HoiIn Jung and HeeEun Kim 1 Department of Preventive Dentistry and Public Oral Health, College of Dentistry, Yonsei University, Seoul 120752, 1 Department of Dental Hygiene, College of Health Science, Gachon University, Incheon 406799, Korea Recently, there are lots methodologies to improve the quality of research in medical and public health fields. One of them is to checking a process of research with a reporting guideline before reporting paper. Especially, reporting guideline for randomized controlled trials (RCTs) is the consolidated standards of reporting trials (CONSORT). Therefore, this review describes the latest version of the CONSORT statement, CONSORT 2010, including intent, background, and contents of this. The CONSORT statement comprises a checklist of essential items that should be included in reports of RCTs and a diagram for documenting the flow of participants through a trial. This report guideline aims at providing guidance to authors about how to improve the reporting of their trials. As consulting the CONSORT, authors could be strictly reported about research methods and results. From this review, we expect to elevate the quality of such research about dental hygiene and to establish the foundation for evidencebased dental hygiene. Key Words: Clinical trial, Evidencebased practice, Randomization, Research report 서론 수많은연구자들은자신이수행한연구결과를논문이라는형식을빌어보고하고, 이를통해독자들은해당연구의가치를판단하고실용가능성을가늠한다. 특히, 의료ㆍ보건분야의연구결과는의료정책입안이나공중보건사업추진및신의료기술등재등관련제도와정책변화에절대적영향력을가질뿐만아니라의학적패러다임을변화시킬수있다. 이러한이유로최근들어의료 보건분야의학술단체는객관적근거를바탕으로연구가수행될수있도록노력하고있으며, 이렇게얻어진결과를바탕으로하는근거 기반의의사결정을강조하고있다. 연구의계획에서부터진행과정과결과보고에이르기까지각수행단계의객관성과정확성및윤리성에대한모니터링은지속적인관심의대상이되고있다. 유수의의학연구저널의편집자들은투고된연구논문의연구방법및결과를투명하게공개하고표준화된지침에따라객관적으로평가할필요성을제기하였다. 따라서그들은연구진행중간과될수있는부분에대한사전점검을위하여연구보고에필수적인중요정보제공을위한보고지침 (reporting guideline) 을개발하기시작하였다. 우리나라치위생분야의연구동향을분석한선행연구에 Received: May 27, 2014, Revised: July 21, 2014, Accepted: July 22, 2014 ISSN 15984478 (Print) / ISSN 22337679 (Online) Correspondence to: HeeEun Kim Department of Dental Hygiene, College of Health Science, Gachon University, 191, Hambangmoero, Yeonsugu, Incheon 406799, Korea Tel: +82328204414, Fax: +82328204370, Email: hekim@gachon.ac.kr Copyright 2014 by the Korean Society of Dental Hygiene Science This is an Open Access article distributed under the terms of the Creative Commons Attribution NonCommercial License (http://creativecommons.org/licenses/ bync/3.0) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
J Dent Hyg Sci Vol. 14, No. 3, 2014 따르면, 과거 12년동안한국치위생과학회지에게재된치위생연구중설문지법을이용한단면연구가 72.3% 로분석되어가장큰비율을차지하는것으로나타났다 1). 이러한연구경향은치위생분야의타학회지도비슷한상황이었다. 이선행연구는최근의료ㆍ보건계열의전반적인연구동향을볼때, 치위생계에서도편향된연구수행에서벗어나임상시험이나치위생중재와같은근거기반의실무 (evidencebased practice, EBP) 를발전시킬수있는다양한주제로의접근이필요하다고하였다. 이와더불어한국치위생과학회지의논문심사의평가기준을더욱강화하여향후게재될논문의질적향상을도모할필요가있음을제안하였다. 이러한근거기반의연구추세에발맞추고치위생관련학술지의질적발전을도모하기위해서는앞서언급한것처럼연구방법론의정확성과신뢰성을갖추기위한제도적장치를마련할필요가있다. 이미 New England Journal of Medicine (NEJM), Lancet, Journal of the American Medical Association (JAMA), British Medical Journal (BMJ) 과같은세계유수의학술지들은논문제출시, 일정한양식의보고지침을따르도록권고함으로써연구보고의질적향상을도모하고있다. 이러한보고지침의대표적인양식은무작위대조군연구 (randomized controlled trials, RCTs) 를위한보고지침인 consolidated standards of reporting trials (CONSORT), 진단정확도에대한연구 (diagnostic accuracy studies) 의완결성을위한 standards for the reporting of diagnostic accuracy studies (STARD), 코호트연구, 환자대조군연구, 단면연구등관찰연구의평가도구로개발된 strengthening the reporting of observational studies in epidemiology (STROBE), 문헌분석과메타분석연구의질을평가하는 preferred reporting items for systematic reviews and metaanalyses (PRISMA) 등이있다. 이들중특히 CONSORT는학계내에서활발히활용되고있는데, 현재 PubMed에등록된의학잡지의 50% 이상이이보고지침에따라연구결과를보고할것을권고하고있다 2,3). 이는 CONSORT의평가대상인 RCTs가근거기반적접근의핵심적인방법론이기때문으로생각된다. 따라서본연구는 CONSORT의내용과특징을소개함으로써치위생연구의계획및수행에도움을주고더나아가 EBP의활성화에기여하고자한다. 본론 1. CONSORT 의소개 CONSORT 는경험적근거 (empirical evidence) 를제공 하는 700여개의연구자료를기반으로 1996년에임상연구자, 통계학자를포함한연구방법론자, 역학자, 의학관련학술지편집자등이참여하여만든 RCTs를위한보고지침의일종이다 4). CONSORT는논문저자들에게시험보고를개선하기위한방법에대한지침을제공하는것을최우선의목적으로한다. 이보고지침을활용함으로써연구자들은자칫소홀할수있는임상시험의내ㆍ외적타당도를점검할수있기때문에임상시험보고의질적향상을도모할수있다. CONSORT는 1996년최초로발표된이래끊임없이학술계의제안및요구를반영하여 2001년과 2010년 2회에걸쳐서개정되었고, 다양한확장판과각항목에대한배경과근거를자세히기술한해설판등을내놓았다 512). CONSORT 는발표 1년만에 RCTs에대한더나은보고 13), 근거기반보건의료를향한중요한한발자국 14), 편향되지않은연구를위한과제 15) 라는제목으로여러의학학술지에그내용이소개되었다. 저자들은논문작성단계는물론이고연구설계시점부터 CONSORT의각항목을참고함으로써연구의질을향상시키고, 독자나편집자는연구결과의도출과정을평가하는데이보고지침을활용할수있다 16). 여러선행연구들은연구진행과정중에이보고지침을준수하도록한결과, 실제로 RCTs들의질이향상되었다고보고하였다 17,18). 이러한성과는 RCTs 외의다른종류의연구를진행함에있어서도이와유사한보고지침을따르도록권고하는계기가되었다 19). 2. CONSORT 2010 statement의구성 2010년에개정된 CONSORT 2010 statement는 RCT 보고서에포함되어야할필수항목인체크리스트 (check list; Table 1) 와피험자들이연구에참여한과정을도식화하기위한순서도 (flow chart; Fig. 1) 로구성되어있다 4). 체크리스트는 25개의항목으로이루어져있는데하나의항목이보다세분화된항목으로나누어져있는경우가있기때문에이를독립적인것으로볼경우총 37개의항목으로이루어져있고, 연구자는각각의항목을근거에입각하여보고하여야한다. 순서도는연구의참가자가선정되고무작위배정되는때부터연구종료시점까지피험자의참여사항을연구진행과정과접목하여명확한그림으로나타낼수있도록구성되어있다. 일반적으로 CONSORT를채택한학술지들은 CONSORT를개발한그룹에서권고하는것처럼제시된양식을변경하지않고그대로사용하고있다 20). 체크리스트의각항목들은논문서술의일반적양식에따라제목및초록, 서론, 연구방법, 연구결과, 고찰로분류되어구 270
정회인 김희은 : 무작위대조군연구의보고지침 Table 1. CONSORT 2010 Checklist of Information to include when Reporting a Randomised Trial Section/topic Item No. Checklist item Reported on page No. Title and abstract 1a Identification as a randomised trial in the title 1b Structured summary of tria design, methods, results, and conclusions (for specific guidance see CONSORT for abstracts) Introduction Background and objectives 2a Scientific background and explanation of rationale 2b Specific objectives or hypotheses Methods Trial design 3a Description of trial design (such as parallel, factorial) including allocation ratio 3b Important changes to methods after trial commencement (such as eligibility criteria), with reasons Participants 4a Eligibility criteria for participants 4b Settings and locations where the data were collected Interventions 5 The interventions for each group with sufficient details to allow replication, including how and when they were actually administer Outcomes 6a Completely defined prespecified primary and secondary outcome measures, including how and when they were assessed 6b Any changes to trial outcomes after the trial commenced, with reasons Sample size 7a How sample size was determined 7b When applicable, explanation of any interim analyses and stopping guidelines Randomisation Sequence generation 8a Method used to generate the random allocation sequence 8b Type of randomisation; details of any restriction (such as blocking and block size) Allocation concealment 9 Mechanism used to implement the random allocation sequence mechanism (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned Implementation 10 Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions Blinding 11a If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how 11b If relevant, description of the similarity of interventions Statistical methods 12a Statistical methods used to compare groups for primary and secondary outcomes 12b Statistical methods used to compare groups for primary and secondary outcomes Results Participant flow (a diagram is 13a For each group, the numbers of participants who were randomly assigned, strongly recommended) received intended treatment, and were analysed for the primary outcome 13b For each group, losses and exclusions after randomisation, together with reasons Recruitment 14a Dates defining the periods of recruitment and followup 14b Why the trial ended or was stopped Baseline data 15 A table showing baseline demographic and clinical characteristics for each group Numbers analysed 16 For each group, number of participants (denominator) included in each analysis and whether the analysis was by original assigned groups Outcomes and estimation 17a For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) 17b For binary outcomes, presentation of both absolute and relative effect sizes is recommended Ancillary analyses 18 Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing prespecified from exploratory Harms 19 All important harms or unintended effects in each group (for specific guidance see CONSORT for harms) Discussion Limitations 20 Trial limitations, addressing sources of potential bias, imprecision, and, if relevant, multiplicity of analyses Generalisability 21 Generalisability (external validity, applicability) of the trial findings 271
J Dent Hyg Sci Vol. 14, No. 3, 2014 Table 1. Continued. Section/topic Item No. Checklist item Discussion Interpretation 22 Interpretation consistent with results, balancing benefits and harms, and Reported on page No. considering other relevant evidence Other information Registration 23 Registration number and name of trial registry Protocol 24 Where the full trial protocol can be accessed, if available Funding 25 Sources of funding and other support (such as supply of drugs), role of funders Adapted from the article of Schulz et al. (BMC Med 8: 18, 2010) 6). CONSORT: consolidated standards of reporting trials. Fig. 1. Flow diagram of the progress through the phases of a parallel randomized trial of two groups (that is, enrolment, intervention allocation, followup, and data analysis). 성되었다. 그리고피험자등록, 연구진행방법및연구비지원기관에대한항목은기타정보로구분되어있다. 이들항목을자세히기술하면다음과같다. 를충분히포함하고있어야한다. 초록에대한보다구체적인지침은별도로기술된문서인초록을위한 CONSORT 21) 와그해설판 22) 을참고할것을권고한다. 1) 제목및초록체크리스트의 1a 항목은제목에피험자가 무작위배정 된연구임을표시하도록하였다. 이는해당연구의성격을확실하게나타낼수있도록하기위함이다. 1b 항목은초록에대한것으로연구설계, 연구방법, 연구결과, 결론을구조화하여요약하도록하였다. 초록은독자가해당논문을평가하는첫번째기준이기때문에간단하지만필요한정보 2) 서론체크리스트의 2a 항목은해당연구에대한과학적인배경과논리적근거를제공하도록하였고, 필요한경우연구에적용한중재방법에대한장ㆍ단점등을제시하도록하였다. 2b 항목은구체적인연구가설과연구목적을구체적으로서술하도록하였다. 연구가설과목적의구분이모호할수도있으나, 연구가설은연구목적보다조금더구체적 272
정회인 김희은 : 무작위대조군연구의보고지침 으로표현되도록하였다. 3) 연구방법 CONSORT는연구가적절한방법으로수행되도록하고이를잘보고할수있도록할목적으로개발되었기때문에연구방법과연구결과에대한권고안을수록한체크리스트의 3a에서 19까지의항목들이 CONSORT 보고지침의핵심이라고할수있다. 3a 항목은병렬설계, 요인설계등연구설계의종류에대하여기술하고피험자들을실험군과대조군에어떠한비율로할당하였는지밝히도록하였다. 3b 항목에서는연구개시후에연구참여및제외조건과같이연구프로토콜중에서중요한부분을변경한경우이사실과이를변경한이유를함께명시하도록하였다. 4a 항목은연구참여및제외조건을, 4b 항목은연구자료를수집한기관과장소를밝히도록하였다. 5 항목은중재에대한것이다. 각군에적용한중재법을자세히설명하여다른연구에서재현 (replication) 할수있도록하였다. 또한이러한중재가실제로언제, 어떻게수행되었는지를보고하도록하였다. 6a 항목은일차그리고이차결과변수 (outcome) 에대한정의와이결과들을평가한방법을기술하도록하였다. 여기서결과변수는임상연구에서중재의효과를나타내는지표또는측정치이다. 6b 항목은 3b 항목과유사하게연구개시이후연구의결과변수가다른것으로바뀌었을경우변경된사실과그이유를명시하도록하였다. 7a 항목은표본크기를어떻게결정하였는지에대한것이다. 일부임상연구는최종목표로한표본크기에이르기전에중간분석 (interin analysis) 을수행함으로써조기에연구를종료할수있는지침을연구프로토콜에포함시키기도한다. 7b 항목은이러한경우에대한것이다. 8a부터 10 항목까지는무작위배정에대한항목들이다. 무작위배정은사람을대상으로한임상연구가인과관계를추론하기위한실험연구로서기능할수있도록해주는핵심이다. 8a는무작위배정을하기위한순서 (sequence) 를만든방법을, 8b 항목은연구에서사용한무작위배정의유형을자세히밝히도록하였다. 예를들어블록무작위배정 (block randomization) 을이용한경우블록의크기와구조등에대하여기술하도록하였다. 9 항목은무작위배정의효과가충분하게작용할수있게해주는눈가림 (blindness) 을가능하게하기위하여무작위배정단계에서배정은폐 (concealment) 가어떻게이루어졌는지기술하도록하였다. 10 항목은무작위배정순서를만든사람과피험자를연구에등록한사람, 그리고피험자를각중재로배정한사람을각각기술하도록하였다. 11a와 11b 항목은눈가림에대한 것이다. 11a는중재에대한배정을마친후눈가림이유지된사람들이누구인지기술하도록하였다. 12a와 12b 항목은통계분석방법에대한것이다. 12a 항목은중재군에대하여일차결과변수와이차결과변수를비교하기위해사용한분석법을, 12b 항목은하위군 (subgroup) 분석과같은부가적분석을기술하도록하였다. 4) 연구결과 CONSORT는연구결과에피험자가연구진행에참여한과정을도식화한순서도를포함시킬것을강력히권장하며구체적인틀을제시하고있다 (Fig. 1). 체크리스트의 13a는임의배정된피험자수, 배정된중재를받은피험자수, 일차결과변수분석이이루어진피험자수를각각기술하도록하였다. 무작위배정된피험자수와배정된중재를받은피험자수, 그리고일차결과분석이이루어진피험자수는서로상이할수있다. 그이유는 A 중재로배정을받았지만중재제공자의실수로 B 중재를받은경우, 피험자가추적기간을포함하여여러번의내원이필요함에도불구하고중도에내원을중단한경우등으로다양하다. 13b는이와같이무작위배정이후발생한중도탈락또는제외된피험자의수와그이유를기술하도록하였다. 14a와 14b 항목은피험자모집에대한것으로피험자모집기간과추적기간, 연구가완료되거나중도종료된이유에대하여기술하도록하였다. 15 항목과 16 항목에서는중재가이루어지기전각중재군의인구사회학적특성및임상적특성이어떠했는지표형식으로정리하고중재가이루어진후각분석마다대상자수가어떠했는지명시하도록하였다. 17a와 17b 항목은연구의최종결과에해당하는부분으로일차결과변수와이차결과변수측정값, 추정된효과크기와그정도 (precision) 를 95% 신뢰구간과같은형태로기술하도록하였고이분형결과변수인경우에는절대적효과크기와상대적효과크기를모두기술할것을권고하였다. 18 항목에서는미리계획된분석으로서탐색적분석과는구분되는부가적분석을한경우를기술하도록하였다. 연구결과부분의마지막항목인 19 항목은연구도중발생한위해에대한것이다. 중요한위해와예상하지못했던부작용이있는경우이를기술하도록했으며이에대한보다구체적인지침인위해를위한 CONSORT 23) 를참고하도록제안하였다. 5) 고찰체크리스트의 20 항목은연구의한계에대한것으로편의 (bias) 또는부정확성을발생시킬수있는요인 (source) 을밝히고다중비교에의해유의한결과가발생되었을가능성 273
J Dent Hyg Sci Vol. 14, No. 3, 2014 이있다면이에대해서도기술하도록하고있다. 21 항목은연구결과가외적타당도와적용가능성을갖춤으로써일반화될수있는것인지를기술하도록하였다. 22 항목은연구결과와일치하는해석을제시하되중재의이점과위험을균형있게기술하도록하였고선행연구의결과도고려할것을권고하였다. 6) 기타정보체크리스트의 23 항목은연구등록정보를, 24 항목은최종프로토콜의공개여부를, 25 항목은연구비지원정보를기술하도록하고있다. 국내에서제공되는연구등록시스템은질병관리본부의임상연구정보서비스 (clinical research information service, CRIS) 이다. 최종프로토콜을공개하는것은재현가능성을높여주므로외적타당도향상에기여한다. 결론 근거기반의학 (evidencebased medicine) 은 1992년임상역학자인 Gordon Guyatt 등에의해처음으로이름지어진이래임상의학의주요방법론으로서굳건하게자리매김하였다 24). 현재근거기반적접근 (evidencebased approach) 은근거기반치의학, 근거기반보건의료, 근거기반간호학등의학외의보건의료영역에서도보편적으로쓰이고있으며이를임상현장에적용하는 EBP에대한요구와관심또한높아지고있다 25). 또한건강보험심사평가원에서근거문헌활용지침을발간하는등의료정책결정기관에서근거기반의결정을강조함에따라근거기반적접근은치위생실무의발전과연관성이클것으로생각된다. EBP의정의는환자를치료함에있어서최신그리고최선의근거를이용하는것이다. 이는타당성있는연구로부터얻어진근거를수집, 평가, 통합한결과와임상가의전문적의견, 환자와환자가족의가치관및선호도를함께고려하여이를임상적결정에이용함으로써이루어진다. EBP는여러연구들의결과를적절하게종합 (synthesis) 하여내린결론을임상에적용한다는점에서단일연구의결과를임상에적용하는연구활용 (research utilization) 과차이가있다. 따라서 EBP를임상현장에정립시키기위해서는질평가를거쳐서타당성을인정받은연구들이다수필요하다. 이러한근거기반적접근을가능하게하는연구방법은 RCTs가대표적이다. 이연구방법은서로다른중재의효과를비교할수있는가장좋은방법론으로서인과관계를타당하게추론할수있다. 그러나부적절하게연구가수행될경우편향 된결과를도출함으로써올바른임상및정책적결정에위해를가할수있다. 따라서 RCTs의질적향상을도모하기위하여 CONSORT를준수하는것은치위생연구의타당성을인정받는바탕이되며, 이를통한질높은근거기반적접근은치위생실무의질또한향상시킬것으로생각된다. 이와더불어향후우리치위생계에도 CONSORT와같은표준화된보고지침을도입하여치위생관련연구과정에강력한근거를제시함으로써국민의구강건강향상은물론이고치위생학의학문적정립과임상치위생학의발전을도모할수있을것으로기대한다. 본연구에서는임상연구의대표적인형태인 RCTs에대한평가도구인 CONSORT의내용만을소개하였으나, 이보고지침이모든임상연구의보고지침이될수는없다. 앞서언급하였듯이다양한형태의임상연구에부합하는여러보고지침들이개발되어있기때문에향후에는 STROBE나 PRISMA와같은보고지침에대한고찰도필요하리라생각된다. 요약 세계유수의의학관련연구저널의편집자들은제출된원고의질을관리하기위하여연구진행의가이드라인역할을할수있는보고지침을개발하여평가에적용하고있다. 따라서본연구는 RCTs를위한보고지침인 CONSORT의 2010년개정판내용과특징을소개함으로써치위생연구의계획및수행에도움을주고더나아가 EBP의활성화에기여하고자하였다. CONSORT는시험보고의질을향상시킬수있도록논문저자들에게보고지침을제공한다. 이보고지침은 RCTs 보고서에반드시포함되어야할필수항목인 25개의체크리스트와연구과정의도식화를위한순서도를제시한다. 저자들은연구설계시점부터 CONSORT 의각항목을참고함으로써연구의질을향상시킬수있다. 따라서우리치위생계에서도이러한보고지침을준수함으로써치위생연구의타당성을높이고, 이러한연구결과를질높은근거기반적치위생실무로접목시켜발전시킬수있을것으로생각된다. References 1. Lee SM, Ahn SY, Han HJ, Han JY, Lee CS, Kim CH: The rsearch trends of papers in the Journal of Dental Hygiene Science. J Dent Hyg Sci 14: 6773, 2014. 2. Davidoff F: News from the international committee of 274
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