Drug-Information Week 3 Primary Literature 2B Study Design PDF

PRIMARY RESOURCES & INTRO TO STUDY DESIGN KRISTIN M. JANZEN, PHARMD, BCPS CLINICAL ASSOCIATE PROFESSOR | PHARMACY PRACTICE OBJECTIVES 1. Compare and contrast journals versus magazines 2. Describe the peer-review process and its role in maintaining the quality of scholarly publications 3. Ide...

PRIMARY RESOURCES & INTRO TO STUDY DESIGN KRISTIN M. JANZEN, PHARMD, BCPS CLINICAL ASSOCIATE PROFESSOR | PHARMACY PRACTICE OBJECTIVES 1. Compare and contrast journals versus magazines 2. Describe the peer-review process and its role in maintaining the quality of scholarly publications 3. Identify potential weaknesses in the peer-review process and in publishing in general 4. Identify funding sources for journals 5. List and define the types of publications found in journals INTRODUCTION What is a periodical? Publications issued at regular intervals Examples: journals, magazines, newspapers What is a journal? A periodical that features scholarly articles written by researchers and practitioners on different subjects Published under a “peer review” process (usually!) Journals may be categorized by scope (see Appendix A) JOURNAL VS. MAGAZINE Categories Journal Magazine disseminate current research disseminate news, trends Intent maintain current awareness promote consumer products education form of entertainment Review process peer-reviewed not peer-reviewed information is referenced most are not referenced Citations bibliography provided Length of article Generally lengthy generally short complex designed to be simple to understand requires understanding of specialized terminology and most are written at grade school level Content complexity knowledge of the subject interpret statistics and results Authors/ investigators clearly listed with credentials and affiliations often not listed nonprofit, scientific or professional societies or institutions for-profit organizations or businesses; large media corporations Sponsorship commercial publishers little advertising full-page ads Advertisements ads usually related to subject or specialty Audience professionals, scholars, researchers, students, instructors general public black-and-white pages, graphics colorful; use of photographs Appearance limited colored pages Example New England Journal of Medicine Time Magazine; Vogue WHAT IS THE PEER-REVIEW PROCESS? ¡ A process used by journals to ensure that articles accepted for publication represents quality scholarship, and is relevant and appropriate for the journal ¡ A research paper is critically evaluated prior to publication (e.g., accuracy, methodology, data presentation and interpretation, writing) ¡ Reviewers or “referees” are scientists and clinicians with in-depth knowledge of the paper’s focus of research or review topic ¡ Overseen by an editor of the journal ¡ How to determine: ¡ Ulrich’s Periodical Directory Online STEPS IN THE PEER REVIEW PROCESS 1. Receive manuscript 2. Assign corresponding editor 3. Select reviewers 4. Receive reviewers’ comments 5. Corresponding editor provides independent critique 6. Editorial staff discuss article and either accept, request revision, or reject 7. If requests revision, journal receives revised manuscript and either accepts revisions or sends it for re-review 8. If manuscript is accepted, small revisions may be requested and made 9. Prepared for publication (takes about 3-6 month from this point until published) CRITICISMS OF THE PEER REVIEW PROCESS ¡ Biased reviewers ¡ Failure to keep marginal papers from being published ¡ Failure to detect errors and improprieties before they become printed ¡ Failure to detect faulty statistical methods ¡ Publication bias ¡ Clinical trials with “positive” results more likely to be published than those with “negative” result ¡ Positive = significant results ¡ Negative = shows no difference PUBLICATION TYPES Type of Articles Description Clinical trial Will discuss later in more detail Observational study Will discuss later in more detail Miscellaneous materials published in ¡CaseMiscellaneous report/case materials published in journals: Will discuss later in more detail journals: series ¡ Abstracts of papers submitted to scientific meetings Abstracts of papers submitted to Survey Generally descriptive in nature ¡ Abstracts of papers published Presents in other data based journals on results of a questionnaire, or review of records scientific meetings and/or other available material ¡ Professional society information Abstracts of papers published in Guidelines Systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances other journals ¡ Conference/ proceedings Define the role of specific diagnostic and treatment modalities in the Professional society information ¡ Question/answer diagnosis and management of patients columns Contain recommendations Conference/ proceedings ¡ Book reviews Review article Compiles, summarizes, and evaluates information previously published on a Question/answer columns ¡ Advertisements subject Review generally includes no new data Book reviews Letter to the editor Written by one or more individuals and addressed to the editor of the Advertisements journal Frequently are written as comments on other articles published in that journal, but sometimes are written to provide new information Editorial Expresses a viewpoint or opinion on a subject Generally used to highlight the opinions of some expert on a paper published in that issue of the journal JOURNAL ECONOMICS Nonprofit vs. profit-making Sources of revenue Voluntary or involuntary subscriptions Support from sponsoring organization Advertisements Primary revenue generated Page charges/sale of reprints ABUSES OF PUBLISHING ¡ Research project results divided into separate publications, rather than a single unifying publication ¡ Publication in more than one journal or other literature source ¡ Scientific fraud ¡ Establishment by academic, government, etc. of guidelines for scientists conducting research (IRB protocols help avoid this) ¡ Reducing and limiting the number of publications reviewed when scientists are considered for tenure ¡ Acceptance of full responsibility for a paper's content by ALL authors instead of the "partial" responsibility many authors claim today (I was only responsible for...) ¡ All authors need to assume full responsibility! MISCELLANEOUS CONSIDERATIONS ¡ Publication of abstract only and not the full article ¡ Disclosure of data/information from a study prior to publication ¡ Most journals will not publish a manuscript/study, if the results have been published to a significant extent elsewhere ¡ Popular press usually comply with an embargo on reporting data from studies until the first day of publication, even though they may receive advanced copies of the manuscript ¡ Quality of the journal: archival quality vs. “throwaway” journal ¡ Means of acquiring manuscripts and other materials for publication ¡ Editorial policies of the journal ¡ *Refer to Categories of Journals by Scope* GENERAL PRINCIPLES OF STUDY DESIGN OBJECTIVES ¡ Identify and describe the different sections of a journal article (e.g., abstract, introduction, methods, etc.) ¡ Describe the different designs and differentiate between the structure of each design (e.g., the point at which a study begins, when data are collected and measured, etc.) ¡ Compare and contrast the similarities and differences between study designs ¡ Given examples of studies, categorize them by their study designs ¡ Identify the three characteristics of descriptive studies and explain the importance of each  Section Usual Content Abstract Overview or summary of the work Highlights of results STRUCTURE OF AN General statement of significance (may have some embellishments) Usual format: study objectives, design, results, conclusion ARTICLE Never make a recommendation just based on abstract! Introduction Background information: history, pathophysiology, clinical presentation Summary of previous work/research Rationale for present study Study objective(s) Methods Study design Subject selection procedures, including inclusion and exclusion criteria Outcome measures and methods of outcome measurement Description of analytic techniques This is a must read! Results What happened? Describe events, or present data for outcome measures (i.e., primary outcomes, secondary outcomes) Use of graphics to summarize findings (e.g., tables, charts, figures) – be cautious! This is meaningless if there is a flaw in the methods section Discussion/ Meaning, significance of work Authors’ critique of study: discussion of limitations and strengths Comments/ Further analysis of data Conclusions Comparison with previous work/ research Disclaimers, equivocations, apologies, speculations, etc. Reader’s job is to read beyond authors’ conclusions based on results/date and strengths/weaknesses References/ Evidence that previous work has been considered Bibliography Background/Introduction Abstract EXAMPLE Background/Introduction STUDY DESIGN Descriptive: document and communicate experiences; begin search for explanations Explanatory: examine etiology, cause, efficacy, using the strategy of comparisons DESCRIPTIVE STUDIES ¡ Commonly used tool in epidemiology (i.e. Foodborne outbreak) ¡ Fundamental to epidemiology is the premise that disease does not occur randomly, that human disease or health condition has causal and preventive factor that can be identified through systematic investigation ¡ 3 important characteristics of descriptive studies (basic tenets of any epidemiologic study): ¡ Person (age, sex, marital status, race and ethnicity, nativity and migration, religion, socioeconomic status) ¡ What patient information do you want to know? ¡ Who is being affected? ¡ Place (within country/international, urban/rural, localized occurrence) ¡ Where is the problem occurring ¡ Time (seasonal/cyclical, point estimate, clustering) ¡ When is the problem occurring? DESCRIPTIVE STUDIES: CASE REPORT & CASE SERIES Definitions Case report: observations of the clinical course of a single patient are described in detail Case series: observations of the clinical course of a group of patients are described in detail Purpose Record events, observations, and activities Communicate significant or interesting findings or observations with the medical community Often serve as the initial step in the formulation of hypotheses Scope Use of new therapy for some condition Treatment of rare disorders Occurrence of a specific adverse drug event Poisoning Unexpected presentations of diseases Examples of Significance Early recognition of drug toxicities and teratogenicity Early identification of potential toxicities of dietary supplements Identifying treatments for rare disorders Limitations Usually is the first evidence Looks like a relationship so it warrants further study Does not draw a solid conclusion but can be used as evidence EXAMPLE: CASE REPORT EXAMPLE: CASE SERIES Citation Series of 5 cases STUDY DESIGN Descriptive: document and communicate experiences; begin search for explanations Explanatory: examine etiology, cause, efficacy, using the strategy of comparisons  Measure/ classify EXPERIMENTAL and compare DESIGN (CLINICAL TRIAL) Begin now and follow through There is an intervention! o Drug vs. no drug (placebo) o Drug 1 vs. drug 2 EXAMPLE: EXPERIMENTAL DESIGN STUDY DESIGN Descriptive: document and communicate experiences; begin search for explanations Explanatory: examine etiology, cause, efficacy, using the strategy of comparisons  Classify and OBSERVATIONAL compare Begin STUDIES: Exposed + CASE-CONTROL Cases People with disease/ DESIGN outcome Exposed - Exposed + Controls People without disease/ outcome Exposed - Past Present Begins in the present and looks to the past for exposure Compares case vs. controls for exposure in the past EXAMPLE: CASE- CONTROL DESIGN STUDY DESIGN Descriptive: document and communicate experiences; begin search for explanations Explanatory: examine etiology, cause, efficacy, using the strategy of comparisons OBSERVATIONAL Measure outcome/ compare STUDIES: FOLLOW-UP Begin Disease/ outcome + DESIGN Exposed + (COHORT Free of disease Disease/ outcome - STUDY) Sample from a defined population Disease/ outcome + Exposed - Exclude Disease/ subjects already outcome - with outcome Present Future Prospective – takes place in present and follows group forward (could be 10-20 years) No intervention! EXAMPLES: FOLLOW-UP DESIGN (COHORT STUDY) American Cancer Society Cancer The Framingham Heart Study Prevention Study 1 ¡ Started in 1948 ¡ Started in 1959 ¡ Identify risk factors for cardiovascular disease ¡ Cigarette smoking and cancer mortality ¡ Population: residents of Framingham, MA, ages 28-62 ¡ Population: U.S. men and women aged 30 years and years older ¡ Follow-up exposure instruments: interview, clinic ¡ Follow-up exposure instruments: self-administered examination questionnaire ¡ Frequency of exposure follow-up: every 2 years ¡ Frequency of exposure follow-up: every 2 years STUDY DESIGN Descriptive: document and communicate experiences; begin search for explanations Explanatory: examine etiology, cause, efficacy, using the strategy of comparisons OBSERVATIONAL STUDIES: CROSS- Begin Measure/ Classify & Compare SECTIONAL Exposure or risk factor + DESIGN Free of disease/ outcome Exposure or risk factor - Sample from a defined population Exposure or Have disease/ risk factor + outcome Exposure or risk factor - Present Snapshot of one point in time (could be on day or months) Prevalence study What is happening right now? EXAMPLE: CROSS-SECTIONAL DESIGN ¡ Birth rates among adolescents aged 15 to 19 years ¡ Prevalence of cigarette smoking among U.S. adolescents from 1974 to 1991 ¡ Prevalence of congenital malformations across maternal age PRIMARY RESOURCES & INTRO TO STUDY DESIGN KRISTIN M. JANZEN, PHARMD, BCPS CLINICAL ASSOCIATE PROFESSOR | PHARMACY PRACTICE