Writing Biomedical Research Papers Ding-I Yang Institute of Brain Science National Yang-Ming University
Essentials of Writing Biomedical Research Papers. Second Edition. By Mimi Zeiger the McGraw-Hill Companies, Inc.
Title • Abstract • Introduction • Materials and Methods
Function of Title • To identify the main topic or the message of the paper • To attract readers
Hypothesis-testing Papers • Stating the topic in the title: effects of X on Y in Z, Y in Z, and other pieces of information. • Stating the message in the title: either in a phrase or in a sentence.
Independent and dependent variables: Effect of X on Y in Z • The standard title of a biomedical research paper is a phrase that identifies the topic of the paper. For a hypothesis-testing paper, the topic includes three pieces of information: the independent variables that you manipulated (X), the dependent variables you observed or measured (Y), and the animal or population and the materials on which you did the work (Z).
Where necessary, two other pieces of information may also be included in the title: the condition of the animals or subjects during the study and the experimental approach. • Always include the animals studied unless in humans. However, when a subpopulation of humans was studied, the subpopulation is always included in the title.
Papers with only dependent variables: Y in Z • Y is the dependent variables that are observed or measured, and Z is the animal or population and the material on which the work was done.
Other information in the title • The condition the subjects or the animals were in during the experiments or the experimental approach. • However, include these pieces of information only if such details are important.
Stating the message in the title: phrase title • If the paper has a strong, unambiguous message supported by strong, unequivocal evidence, the title of the paper can state the message (the answer to the question) in a phrase or in a sentence. • In a phrase title, the message is expressed by either an adjective or a noun (depending on the verb used in the question and answer) placed before the dependent variable at the beginning of the title.
Stating the message in the title: sentence title • Using a sentence to state a message is stronger than using a phrase is. This is because verbs convey action more powerfully than nouns or adjectives. Thus, the same title stated as a phrase and as a sentence will sound stronger as a sentence. • However, you should use a sentence title only if you have a clear message backed up by solid evidence.
Descriptive Papers • For describing a new structure, the title names the structure being described and states its key function. • The structure comes first in the title followed by the function.
Methods Papers • A method, an apparatus, or a material: use the name in the title if the method has a name. If the method does not have a name, use a category term such as “method” or “apparatus”. • Its purpose: for doing… • Name the animal or specific population in humans the method is used for. • Whether the method is new or improved (for…., describe the most important advantage of this method, or just “improved” if it is difficult to name a specific important feature)
Hallmarks of a Good Title Is….. • Accurately, completely, and specifically identifies the main topic or the message of the paper, either in a sentence or in a phrase • Unambiguous • Concise • To begin with an important term
Accurate • For hypothesis-testing paper, check that your title is accurate by comparing it with the question and answer. • For a descriptive paper, the terms used for the structure and the function in the title should be the same as those in the message stated in the Introduction and the Discussion. • For a method paper, the name of the method, its purpose, and the animal or population should be the same in the title as in the Introduction, Discussion, and Abstract.
Complete • In a paper with two messages, select the most important one for the title if you cannot create a title that reflect both messages. • With several independent/dependent variables without a category term available to include them all, select the most important independent and dependent variable for the title. • Announcing the main variables of the paper is stronger then trying to fit all into the title.
Specific • And: use it only for parallel terms, NOT for joining the independent and dependent variables in the “X and Y in Z” instead of “Effect of X on Y in Z”. “And” does not implicate any relationship between X and Y. • With: change with to a more specific word.
Unambiguous • Avoid noun cluster (noun + noun: Blood-Brain Barrier CSF pH Regulation) • Do not use abbreviation. Even if an abbreviation is well known in one specialty, it could be confusing to readers from other specialties. • However, when the abbreviations are better known than the words they stand for, such as DNA and RNA, use abbreviations. In addition, abbreviations for chemicals, such as NO (nitric oxide), can be used. Nevertheless, if you have space, spell it out if it is a short familiar word like “oxygen”.
Concise • A concise title is a short title without sacrificing accuracy, completeness, specificity, or clarity. • Keep your titles shorter than 100 characters and spaces (120 is the outer limit). But how???
To make titles concise… • Omit unnecessary words such as “nature of”, “studies of”, “effects of”, omit “the” at the beginning of the title. • Compact the necessary words as tightly as possible by category terms (liver, blood…vs. extra-pulmonary) adjectives to express a message (reduced vs. reduction in), and noun clusters (NGF protection vs. protection by NGF).
Important word first • Either the dependent variable or the independent variable can be the most important word (considering the journal you are submitting your manuscript, who are the readers?).
Subtitles • A technique for putting an important word first is to use a main title followed by a subtitle. • The main title states the general topic and the subtitle states the specific topic. • A subtitle is separated from the main title by a colon (:).
Relation of the subtitle to the main title • Material: Variables Studied • Variable Studied: Experimental Approach • Variable: Function • You need to figure out the appropriate preposition between the subtitle and the main title in order to reconstruct the full title. • Whatever the relation, a crucial element in the use of subtitles is that the relation between the subtitle and the main title must be obvious. • Subtitles for a series of papers: a risky idea…. • Use subtitle only if it is the best way to put an important word first.
Details • Word choice: “increased” and “reduced” should be used to modify quantitative words; “improved” and “impaired” should be used for qualitative words. • Determining the length of a title: count both characters (a category term for letters and punctuation marks) and spaces between words.
Running titles • Also known as running heads. Short phrases that appear at the top or bottom of every page, or every other page, in a journal article. The purpose is to identify the article. Some journals use the authors’ names instead. • The running title is shorter then the title (probably less specific?).
Running titles for three types of articles • Hypothesis-testing papers: name the independent and dependent variables, but not the animal/population. • Descriptive papers: name the structure and a brief version of the function. • Method papers: name the method only or the population
Contents of the Abstracts for Hypothesis-Testing Papers • Question: as a question or as a hypothesis • Experiments: state the materials and experimental approach, including dependent and independent variables • Results: give data, if at all, only in percent change • Answer: state the answer to the question. Do not write vague statements.
Background and Implication • At the beginning of the abstract, you can include one or two sentences for background introduction. This is for those readers who may wonder why you are asking your question. This sentence should be the same as that given at the beginning of the Introduction, only briefer. • You can include a sentence stating the implication, speculation or recommendation, at the end of the abstract. However, DO NOT substitute implication for answer.
Organization of the Abstracts for Hypothesis-Testing Papers • Overall organization • Organization of results
Overall Organization • Often the details of the experiments done (specific independent and dependent variables, doses, methods) are given in the sentences that state the results found. This organizational strategy avoids repetition. • Although the overall organization of the abstract follows the organization of the paper, the abstract does not give equal weight to all sections of the paper. The abstract include much of the Introduction but only a few details from Methods, only key results/data from Results, and only the answer and maybe an implication from the Discussion.
Organization of Results • If you include two or more results in the abstract, arrange them in a logical order, such as chronological order, most to least important or least to most important. • When organizing from most to least important, describe control results last (if you include them at all).
Writing of the Abstracts for Hypothesis-Testing Papers • Continuity • Signaling Topics • Verb Tense • Sentence Structure • Word Choice • Abbreviations
Continuity • Repeat key terms • Use consistent order for details • Keep the same point of view in the question and the answer • Use either parallel form or consistent point of view for comparisons and other parallel ideas (Example 10.3: four different drugs).
Signaling Topics • Abstracts are conventionally written as one single paragraph, albeit with exceptions. Therefore, it helps the readers if you signal the parts of an abstract both visually (by starting a new sentence) and verbally (by signaling the topic at the beginning of the sentence). • Begin a new sentence for the question, the results found, and the answer. The question and the experiment done are often in the same sentence, so only the question needs to be signaled. However, if the sentence is too long, the question and experiment can be in separate sentences, each having its own signal.
Signaling Topics • Be careful to distinguish the implication from the answer by using a cautious signal such as “These results suggest that …..”. The verb in the suggestion can also be cautious, “may inhibit”, “may play a role in,” etc. • Always put answer and implication in separate sentences.
Verb Tense and Word Choice • Verb tenses in the abstract should be the same as those in the paper: present tentse for the question and the answer; past tense for the experiments done and the results found. • Use simple words. Avoid jargon.
Abbreviations • Avoid abbreviations wherever possible. You can use widely accepted abbreviations such as DNA, but semi-standard and nonstandard abbreviations should be avoided. • If you must use a nonstandard abbreviation that is not widely accepted, define it the first time you use it in the abstract. Try to have only one abbreviation in an abstract and certainly no more than three.
Length of the Abstracts for Hypothesis-Testing Papers • Most journals limit the length of the abstract usually to 250 words or less. It is better to keep it within 150 words. • If no limit is stated, make your abstract no longer than the abstracts in recent issues of the journal. • If you can summarize your apper in fewer words than the maximum allowed, do so. Do not add more and more details. The overview is easiest to see in a short abstract. • Do not write in the style of a telegram; that is, do not omit necessary “a”, “an” and “the”.
Abstracts of Descriptive Papers • Contents and Organization • Writing including signaling topics, verb tense, sentence structure, word choice, and abbreviations.
Contents of the Abstracts for Descriptive Papers • The message of the paper • The results that support the message • The implication of the message • If necessary, background information can be added at the beginning of the abstract.
Organization • Since there is no hypothesis to be tested in descriptive papers, the message is stated at the beginning of the abstract. • The results that support the message come immediately after the message, to convince the reader that the message is true. • The implication is stated at the end. Methods, if any, are included in the sentences that state the results.
Writing of the Abstracts for Descriptive Papers • Only the message and the implication are signaled in a descriptive abstract. • Verb tenses are a little trickier in descriptive abstracts than in hypothesis-testing abstracts. If a statement is still true, use present tense; if the statement is about something done or found in the past, use past tense. Use present tense to describe a structure; use past tense to describe the result of an experiment. • For implications, the verbs can be cautious or not (use the present tense).
As usual, sentences should be short, words should be simple, and abbreviations should be avoided. • Keep the abstract as short as possible, never more than 250 words.
Common Problems in Abstracts of Hypothesis-Testing Papers • Deviations from the standard for, including omitting the question, stating the question only vaguely, stating an implication instead of an answer, and substituting a descriptive abstract for a hypothesis-testing abstract.
Question omitted or stated vaguely • Without the question, the readers read the abstract blindly. They understand the abstract only at the end and then have to reread it to fit the details into the picture. • In a question stated vaguely, only the dependent variable is named, like “Y was studied”. You should use a verb to join the independent and dependent variables. For questions that have only a dependent variable, the specific aspect of the dependent variable studied must be named.
Answer Not Stated • The function of the abstract is to provide an overview of the story and the answer is the culmination of the story, not stating the answer undermines the abstract. • Further, most of the readers do not realize that the answer is missing, so they could be confused without knowing it. • Therefore, for a clear abstract that has an unmistakable message, the answer must be stated and clearly signaled. • The answer should use the same key terms, the same point of view, and the same verb as in the question, so it is easy to see that the answer answers the question asked.
Substitution of a Descriptive Abstract for a Hypothesis-Testing Abstract • A descriptive abstract implies that you had no hypothesis, but rather made a discovery. This implication is misleading and makes the story of the science unclear. • If your study tested a hypothesis or asked a question, you should include the hypothesis in the abstract and write a hypothesis-testing abstract, not a descriptive abstract.
To ensure that your abstract provides a clear overview, you must • State the question you asked • Make the statement of the question specific rather than vague or general (by naming both the independent and the dependent variables, using the same key terms and the same point of view as in the answer, using the same verb as in the answer) • State the answer clearly • Write a hypothesis-testing abstract, not a descriptive abstract, when you are testing a hypothesis.