How to write in science Shah Ebrahim Co-Editor, International Journal of Epidemiology Professor of Public Health London School of Hygiene & Tropical Medicine & South Asia Network for Chronic Disease Above all: You must be clear. Why? To help the reader and avoid misunderstandings! To clarify your own thinking Overview of session •  General principles •  Nuts and bolts •  The sections of research paper •  Technicalities of writing for journals General principles Characteristics of scientific writing •  Appropriateness •  Balance •  Persuasiveness •  Brevity •  Consistency •  Precision •  Sincerity • Clarity The four stages of composition 1: Think •  •  •  •  •  Define purpose and scope Who are you writing for? What readers need to know. Allocate available time Who else is involved? Manage your time Phases and resources The four stages of composition 2: Plan •  Draft an outline •  Effective beginning •  Put topics in order •  End •  Set the outline aside •  Liaise with others Battle plan The four stages of composition. 3. Write •  Write so that you can easily revise •  Use outline •  Try to complete your first draft of the paper, or of a section, in one sitting Write as you like ம"க$%: &பா)*+,& ம"க$% வ,த ஏ0 இ,2யா 4மான6, தைர இற":‌6;&, ஓ= தள?2@ Aைல த=மாC ஓD 4ப?2E:Fளான& Migration is a source of economic gain but also of losses (stuff from previous intro). Cite IJE paper. Avoid distractions The four stages of composition 4: Check Read draft aloud •  Main points emphasised? •  Anything essential missing? •  Meaning of each sentence clear and correct? •  Think of the reader: style, vocab Revise •  Ask two readers to check your corrected draft •  Revise again Turn to Exercise 1. Which text is easier to read aloud? A or B? WORDS MATTER! EXERCISE: PRINCIPLES OF WORD CHOICE •  Look at the underlined parts in the following sentences •  Could the be written better? •  What is the principle of word choice that is violated •  If you are not sure, guess. •  Just change the words not the sentence structure 1.  The odds ratio was drastically reduced when adjusted for confounders. 2.  Participants were asked to fast for several hours before venapuncture. 3.  The cells were exposed to with lipoprotein-deficient serum for 48 h 4.  With inhalation of salbutamol, lung function improved. Principle? 1.  The odds ratio was attenuated when adjusted for confounders. 2.  Participants were asked to fast for eight hours before venapuncture. 3.  The cells were incubated with lipoprotein-deficient serum for 48 h 4.  After inhalation of salbutamol, lung compliance decreased. Principle? PRECISION 1.  Blood samples were drawn from 5 female and 3 male children at 1, 2, 3 and 4 h following the initiation of dialysis. 2.  Rapid dehydration was caused by elevated body temperature. 3.  Meningococcal infection causes erythematous, peticial lesions in severe cases. 4.  Sampling was indicative of suboptimal participation of younger men Principle? 1.  Blood samples were drawn from 5 girls and 3 boys at 1, 2, 3 and 4 h after starting dialysis. 2.  Rapid dehydration was caused by fever. 3.  Meningococcal infection causes a red blotchy rash in severe cases. 4.  Sampling was showed poor participation of younger men Simplicity Principle? 1.  After 4 h of interviewing, we ended the interview process. 2.  Socio-economic status and mortality was examined and found to vary considerably. 3.  Obesity decreased in families with lower household incomes but smoking increased in poorer households. Both the decrease in obesity and the increase in smoking were greater when only men were included in the analyses. Principle? 1.  After 4 hours, we ended the interview. 2.  Socio-economic status and mortality varied considerably. 3.  Obesity decreased in families with lower household incomes but smoking increased. Both trends were greater among men. Principle? Necessity 1.  This study assessed the feasibility of integrating quacks into governmental malaria treatment services. 2.  While the male focus group chewed the fat, the female focus group demonstrated child-cleaning practices. 3.  Lymphoedema isn’t perceived as sufficient reason to spend money on consulting a doctor. Principle? 1.  This study assessed the feasibility of integrating all health practitioners into governmental malaria treatment services. 2.  While the male focus group discussed the principles, the female focus group demonstrated child-cleaning practices. 3.  Lymphoedema isn’t perceived as sufficient reason to consult a doctor. Principle? Appropriate register Principles of word choice •  Precision •  Simplicity •  Necessity •  Appropriate register General vs specific •  Avoid clichés and over used words: . (e.g. without doubt, deliver care, address a problem, day-to-day basis, gold standard) •  Use more accurate and precise words when you can •  Avoid trendy euphemisms resource-poor = poor policy endpoints = results Exercise Correct these phrases. Why is this needed? five different villages a specific example available evidence observed values Correct these phrases. Why is this needed? five different villages= five dissimilar villages, five similar villages a specific example = an unambiguous example, a detailed example available evidence = evidence on hand, obtainable evidence observed values =observed measurements, observed standards Improving precision = clearer meaning Exercise: Make these phrases concise. •  are found to be in agreement •  has the ability to •  in no case did any of the controls develop lesions •  mortality in patients in Group 1 was higher when compared to patients in Group 2 •  population growth increased by 100% Make these phrases concise. •  are found to be in agreement = agreed •  has the ability to = able to •  in no case did any of the controls develop lesions = none of the controls •  mortality in patients in Group 1 was higher when compared to patients in Group 2 = mortality was higher in group 1 than group 2 •  population growth increased by 100% = the population doubled Sentences 7 Make the message the grammatical subject of the sentence The message is that the index case came from Mumbai. •  It was discovered that the index case originated in Mumbai. •  The index case originated in Mumbai. Put the action in the verb phrase Measurement of the median distance to the closest health post was done. We measured the median distance to the closest health post. Mass administration of antibiotics occurred twice in 2004. Antibiotics were mass administered twice in 2004. Avoid putting the action as a NOUN An increase in chloroquine resistance occurred. Chloroquine resistance increased. With parasitaemia of longer duration or severer degree cognitive ability deteriorates progressively. What is parasitaemia doing? When parasitaemia lasts longer or is more severe, cognitive ability deteriorates progressively. Verbs are the lifeblood of sentences. To weaken them or to omit them saps the sentence of its liveliness and makes it difficult and dense to read. Avoid noun clusters range of patient data communication requirements can have six! meanings: •  Meet requirements for communicating patients' data •  Meet data-communication requirements of a wide range of patients •  Meet the requirements for communicating data from a wide range of patients •  Meet the requirements for communicating data to a wide range of patients •  Meet the requirements for communicating a wide range of data about patients •  Meet the requirements for communicating data about wide range of patients Write short sentences Do not cram too many ideas in one sentence. Success of this method crucially depends on timely delivery of the drug and on correct dosing, as delayed or incorrect administration would lead to development of resistance in the population, which we saw in Kosovo, where migrant workers were missed and children overdosed, resulting in a fresh epidemic, comatose infants and loss of trust in the health services, something the government cannot afford and must avoid in the future. Point of view Author’s point of view + active voice + more lively and natural - does not make the topic the subject of the sentence - may be inappropriate if fieldworkers or technicians actually did the work - gets obnoxious with overuse Point of view of the experiment or study - passive voice - a bit dull + makes topic the subject + emphasises what is important To keep writing interesting, alternate: •  Use ‚ we for sentences that move the story forward, i.e., in the study design subsection but not for methods of measurement. Paragraphs •  Mini-story •  One paragraph for each aspect of the subject (topic) •  Use transitions to make clear the continuity between sentences •  General approach: Overview first, then details. •  To identify the topic, use a key term, and repeat it exactly. Patterns of organization for paragraphs Most to least important Announced order Pro – con Funnel (Introduction section) Chronological order (Methods & Results sections) Problem – solution Continuity •  Repeat key terms. •  Use transitions to indicate the train of thought. •  Keep a consistent order. •  Keep a consistent point of view. Keep a consistent order To establish the chain of transmission, we had to collect venous blood samples from the suspected 1index case, from his 2immediate family, from his 3recent contacts in the village and from 4trade partners outside the village. The sample from the 1index case could be obtained in hospital; to collect the samples from his 2immediate family, we visited his compound. Obtaining samples from his 3recent contacts required that we spoke to the village children to identify the contacts, and to then visit them at home. To collect samples from 4 trade partners outside the village, we had to interview the local taxi companies …. Writing a scientific paper •  Interactive work •  Titles and abstracts Titles and abstracts Hallmarks of a good title •  Accurate: use same key terms in title as in paper •  Complete: include all necessary information – e.g. study design •  Unambiguous: avoid abbreviations •  Concise: omit unnecessary words •  Important word first •  Engaging (e.g., a question) What is wrong with this title? A brief account of smoking by Tibetan migrants and modification by the effects of living conditions, SEP and length of time spent in India. A possible improvement? A brief account of smoking by Tibetan migrants, COPD and modification by the effects of living conditions, SEP and length of time spent in India. Smoking in Tibetan migrants to India is associated with chronic obstructive airways disease: a cross-sectional survey The Abstract EXERCISE 1 Abstract Abstract Abstracts What? Why? How? Who? Where? When? Findings? Conclusion? Only essential information following the overall structure of the paper. Structured vs. unstructured abstract •  Structure focuses the mind Facilitates conciseness Is easier to read and retain •  Write a structured abstract before you start and again when the paper is finished The Introduction EXERCISE 2 Page 1 EXERCISE 1 3 1 2 4 Role in the Story Line •  First step •  Research question (hypothesis-testing paper) •  Message (descriptive paper) •  New or improved method, apparatus or material (methods paper) •  Working metaphor: Funnel Content •  •  •  •  •  •  Known Unknown Question Material or population Study design References: only the first, the most important, the most recent •  Newness, importance (optional) No answers, results, implications Funnel principle S t a r t b r o a d l y N a r r o w s t e p by s t e p to a focal point From the Known to the Unknown to the Question Step 1: What is known •  In first sentence, state general topic of the paper •  Explain background/motivation in a few sentences or paragraphs •  Within this framework, narrow down to what is not known in the research area Step 2: What is unknown •  Brief statement, usually one sentence. •  Important because it indicates that work is new links Known and Question, creating the story line Writing about what is unknown Clearest if flagged: … is unknown … needs to be determined … is unclear ... However, it is not yet known how low social support leads to increased mortality.... To answer this question, we randomly allocated participants to a social support intervention or to usual care ... Step 3: Your Research Question •  Specific topic of the paper •  Must inevitably follow from Known and Unknown Importance Best placed at the begining of the Introduction. Make sure the importance of the work is evident – state if necessary. Remember modesty. To develop the story line: •  Start a new paragraph for each of Known, Unknown, Question if the Introduction is long •  Use transition phrases and words •  Repeat key terms Length of the introduction Typically 1 double-spaced A4 page, i.e., 250-300 words Do not exceed 2 pages or 600 words Materials and Methods EXERCISE 3 Materials and methods •  •  •  •  •  •  What is the study design? What is the independent variable/ intervention? What are the dependent variables? How were the data collected and analysed? What is the sample size? Could you redo this study from the methods as reported here? •  Readability? Page 2 EXERCISE 2 Page 2 EXERCISE 2 Functions •  Sufficient detail to permit evaluation and replication of your work •  Hypothesis-testing papers: what you did to answer the research question •  Descriptive studies: what you did to obtain the message •  Methods papers: (1) new method in detail; (2) what experiments done to test the new method Role in the Story Line The plot thickens. Overview of the experiments or study, the plan Participants •  Age, Sex, Race •  Selection process •  State of health or disease •  Specific medical or surgical management •  Ethical approval What constitutes sufficient detail? Study design (overview of the methods) •  Questions asked •  Independent variables = interventions •  Dependent variables = measured variables •  Comparison groups •  Sample size – prior estimates of requirements made? •  Methods, laboratory assays and equipment – Well-known: reference only – Less well-known or modified: essential features & reference •  If in doubt, give more detail Statistical analysis •  Tests used and which measurements they compare. Only reference uncommon tests •  Program used including version/release number •  Sample size if it is not obvious from study design •  P values + 95% Confidence Intervals Overall organization of M&M Generic subheadings Study subjects Study design Interventions/exposures Methods of measurement Calculations Analysis of data Ethical approval The Results EXERCISE 4 Page 3 EXERCISE 3 Page 3 EXERCISE 3 No strong evidence of associations between any exposure and phlegm were found. Functions •  State results of experiments described in M&M section •  Direct the reader to tables and figures •  In terms of story line: the plot unfolds •  Working metaphor: snapshot Content of the Results section •  Report only results pertinent to the research question stated in the Introduction •  Report results whether or not they support your hypotheses •  Present data in figures and tables and refer to these; mention only the most important data in the text Results vs. Data Data are facts, often numbers, obtained from experiments and observations. Raw data = e.g., all bodyweights measured in a newborn population Summarized data = e.g., mean plus standard deviation Transformed data = e.g., percent of control Results are general statements that interpret data, i.e., the meaning of the data. Data can rarely stand alone. The result should be stated. Example: Data but no result In the 20 control subjects, the mean resting blood pressure was 85 ± 5 (SD) mmHg. In the 30 tennis players, the mean resting blood pressure was 94 ± 3 mmHg. Revision A: Result but no indication of magnitude The mean resting blood pressure was higher in the 30 tennis players than in the 20 control subjects [94 ±3 (SD) vs. 85 ± 5 mmHg, P < 0.02]. Revision B: Result and general idea of the magnitude The mean resting blood pressure was 10% higher in the 30 tennis players than in the 20 control subjects [94 ±3 (SD) vs. 85 ± 5 mmHg, P < 0.02]. Data •  must be accurate. •  must be internally consistent For example, each percentage should show the same level of exactness, such as 1 or 2 digits after the period. If a value is given in several places, i.e. in the Results, in the Discussion, in a figure or table, it must be same everywhere. Statistical analysis results •  Interpretation of confidence intervals should focus on the implications (clinical importance) of the range of values in the interval •  Avoid the term „statistically significant“ the strength of evidence for or against the null hypothesis is indexed by the P value. The smaller the P value, the stronger is the evidence Statistical analysis results •  take a very sceptical view of subgroup analyses in clinical trials and observational studies. •  In observational studies considerations of confounding and bias are as important as statistical significance See: Sterne J, Davey Smith G. BMJ 2001;322:226–31 The Discussion EXERCISE 5 Page 4 EXERCISE 4 Page 4 EXERCISE 4 Page 4 EXERCISE 4 (CONT) Functions and Content •  Answer research question(s) •  Explain answers •  Contextualise •  Draw conclusions Story Line: Denouement •  What we have learnt and its implications •  Hypothesis-testing paper: true / false •  Descriptive paper: key features of the observations described + implications •  Methods paper: advantages and disadvantages, applications Question-answer match Research question in Introduction: Does mass administration of artemisinin induce resistance in P. falciparum? Answer in Discussion: This study shows that mass administration of artemisinin induces/does not induce resistance in P. falciparum. Giving credit to yourself and others •  Mention other people’s supporting results These results thus lend further credence to X’s earlier suggestion that … Y previously hypothesised that … . In this study we found that a similar situation emerges for … •  If your work pulls together a lot of loose threads, say so. This reconstruction, which incorporates and confirms the separate observations of X, Y and Z (refs), includes several new observations that provide a more complete understanding of … •  Be matter-of-fact. Defending your answer Necessary if •  other answers have been proposed for the question you asked •  other answers are easy to imagine Explain both •  why your answer is satisfactory and •  why others are not Examples for defending an answer “In this study we found that the effects of migration on obesity occurred within 5 years. We believe that this duration is credible as increases in dietary intake and adoption of sedentary habits are rapid after migration. However, much longer durations have been reported by other investigators 6, 7. But their study populations were subject to seasonal migration and substantial losses to follow up. We suspect that valid estimates of migration effects can only be established in relatively stable populations, such as ours … “ “Apparent discrepancies between our human growth hormone values and those of earlier studies27,48 may be due to differences in the study design …” Conflicting results •  •  mention explain “This finding cannot be attributed to increased calorie intake of urban men, since values were no different from those of rural dwelling men. Rather, it appears that physical activity levels were higher in rural men, allowing them to maintain their body mass index rather than become obese.” Newness of your findings •  should be established in the Introduction •  To remind the reader, contrast: “Associations with social isolation and self-ratings measures of ill-health have been reported 38-40. In this study, we report a comprehensive, clinically validated, assessment of mental health status...” Unexpected findings •  signal at the beginning •  explain …A surprising finding was that bug-o-kill did not eliminate the parasite, but that it induced somnolence in human subjects. We suggest two possible explanations: … If these explanations are correct, they imply that bug-o-kill may be used to treat sleeplessness …” Shortcomings and presuppositions Explain •  limitations •  weak study design •  basic assumptions If the explanations are only 1-2 sentences long, think harder about why the work could be considered flawed or inadequate. Reviewers will come up with a very long list for sure! Importance of your work •  •  •  •  Obvious importance may not need to be established. Applications applications (X will/can … do Y), Implications our results suggest/ imply that X may/might Recommendations we recommend that … should/must Speculation gives rise to the speculation that X does Y Place at the end of Discussion section. Organization of the Discussion •  Start: answer research question; support answer with results •  Continue: (1) put your work in context, (2) discussing limitations and assumptions. •  Finish: Indicate applications/implications. How not to begin the Discussion •  with a second Introduction •  with a summary of the results •  with secondary information How to end the Discussion: Make a point •  Signal the end (“In summary, …” “In conclusion, we …”) •  Indicate the importance of the work by stating its uses. How not to end a Discussion •  stating that further research/studies are needed •  claiming research territory by staking out your next project •  claiming that your study is the only/first one to answer the research question Subsections Subheadings are not necessary, unless: •  Discussion exceeds 1000 words •  Discussion contains 3+ subsections each dealing with a separate major topic •  But can be useful in drafting to ensure you don’t overlook something Conclusions •  Link conclusion to goal of your study –  e.g. should provide the answer to the question posed in introduction –  should make it clear whether hypothesis was or was not supported by the data •  Should not over-reach into areas not covered by the research •  Beware data  conclusion mismatches Acknowledgements •  Contributors •  Funding sources •  Reviewers A brief comment on plagiarism •  Don’t do it – editors check! •  Word for word cut and paste is plagiarism •  Using quote marks “There is no more important question than finding the best means of controlling the obesity epidemic in China” Popkin 2011. is fine. Technicalities of writing for journals Step 1: Writing up – formal aspects One common, reader-friendly font No more than 2 sublevels Ask colleague to proofread Step 2: Fitting your manuscript to the formal requirements of your target journal •  Read the instructions. •  Use a reference software (e.g. Endnote) for ease of changing citation format •  Stick to word count limits •  Be realistic about where to send your manuscript •  Check and recheck references. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi •  Get permission to reproduce text or graphics from a previous publication Step 3: Get all authors on board BEFORE you submit •  Authorship = must fit the journal’s criteria – being the boss is insufficient •  Agree on the final text and send it to each author. •  Decide on the order in which authors are to be named. •  Decide who gets acknowledged. •  Agree on corresponding author. •  Describe each author’s role, collect signatures •  Declare conflicts of interests, if any. •  Make sure you have copies of ethical approval documents. Step 4: Check the STROBE* guidelines http://www.strobe-statement.org/ •  These guidelines are intended to help authors to produce good descriptions of epidemiological studies •  You should certainly ensure you cover all the points •  Several journals have decided to use these guidelines in reviewing epidemiological papers *STrengthening the Reporting of OBservational studies in Epidemiology Step 4: Submit paper for peer review •  Write a short!!! cover letter •  Include authorship statement, all authors’ contact details, and, as required, declaration of interests, the copyright transfer and suggestions for reviewers if applicable. •  Expect acknowledgement of receipt within a week. •  Expect feedback after 8-12 weeks. Step 5: Revision •  Stick to the time frame given by the editor. •  Make your revision as easy to evaluate as possible. •  Include a revision with changes tracked and one without. •  You do not always have to agree with the reviewers, but you must comment on each suggestion! •  Expect final decision in another 6-8 weeks. Step 6: Acceptance •  You should, again, ensure that all authors have the version of the paper that is to be published. •  Some journals will inform you when the paper is scheduled to appear. •  Make sure the editors have contact details of at least two authors! Step 7: Proofs The responsibility for correctness lies with you, the author! Return the corrected proofs as soon as possible. Most common step – REJECTION! •  No-one likes a rejection letter •  At IJE we reject 90+% of manuscripts •  Everyone gets upset – so don’t take it personally •  Leave it a week and then re-read your paper and the reviewers’ comments •  Discuss with colleagues •  Try again – taking the comments into account – it may go the same reviewers! Summary •  •  •  •  •  •  •  1: Writing up – formal aspects 2: Fitting manuscript to journal 3: Get all authors on board 4: Submit paper for peer review 5: Revision 6: Acceptance 7: Proofs GOOD LUCK!!