Every time you write something, whether it is a note to a friend or a paper for class, you write with an audience and purpose in mind. It is probably second nature to you to think of the audience and purposes in these more familiar situations and to tailor your writing accordingly. It may be less obvious who your scientific audience is or how you can tailor your scientific writing to better achieve your purpose.

To write effectively, you must identify the audience you are trying to reach. When writing lab reports in your introductory level science courses, your audience was likely only your professor. In more professional types of scientific writing, this is not the case. Your professor (or research advisor) may still may be one member of your audience, but will your classmates also be reading your paper? Will your paper be shared with others in the department? Submitted for publication? Who reads the articles in that publication? Who decides whether your paper will be accepted for publication? Whether real or simply intended for the purposes of an assignment, these “intended” groups should direct what and how you write.

When identifying your audience, ask yourself “Who am I writing for?”

    • Is it a specific person, an organization, a diverse group of people with varying needs?
    • What is my audience’s background knowledge, training, or experience in the field? In this specific topic?
    • What does my audience need to know? find useful? find interesting?
    • What does my audience expect to learn from me?

To write effectively, you must identify the purpose of your writing. The purpose of jokes is to make people laugh. The purpose of textbooks is to teach. The purpose of professional scientific writing is often to share original findings and explain the significance of the findings, but other purposes are possible, too. The purpose for writing scientific grants, for example, is to convince someone to fund your research, typically by persuading them that your idea is original, important, and feasible and that you are the right person to carry out the work. When you focus on your purpose for writing, you are acknowledging that you are trying to achieve something with your writing.


When identifying your purpose, ask yourself

  • Why am I writing?
  • What am I trying to achieve?
  • What does my writing need to do in order to be effective?
  • What would success look like for this piece of writing?


Let’s use an example to explore how Audience and Purpose influence what and how we write.

Imagine that you are writing a headline for an article about global warming. How would you write that headline differently in order to achieve the following purposes?

1) To teach; 2) To impress; 3) To persuade; 4) To spark interest

Some possibilities are:

  1. To teach: “Global CO2 Levels Surpass 400 ppm in March”
  2. To impress: “CO2 Reaches Highest Levels on Earth in 3 Million Years”
  3. To persuade: “Toxic CO2 Milestone Warrants Action by Lawmakers”
  4. To spark interest: “March Made Climate History, and not in a Good Way”



Aud-1: Practice exercise

Now let’s flip the exercise. Can you identify a likely intended purpose and audience in a given piece of writing? How do the purpose and audience differ in the following sets of sentences (compare a and b)? Note what features of the writing led to your conclusions regarding the intended purpose and audience.

SET #1

a. Porosity was determined using the following method: samples were dried in an oven at 40 °C; sample dimensions and dry mass were recorded; samples were blotted and weighted to obtain saturated mass.

b. Determine porosity using the following method: 1. Dry samples in an oven at 40 ˚C overnight. 2. Record the dimensions and the dry mass of each sample. 3. Blot each sample using MMX Oval paper. 4. Weigh each sample and record its saturated mass.


SET #2: (Adapted from Costanza-Robinson and Brusseau 2002)

a. Although several methods for measuring air-water interfacial area have been proposed, each with associated advantages and disadvantages, it is not clear that the methods yield consistent information. It is possible, for example, that the various methods probe different physical interfacial domains within the soil.

b.The current study was conducted to evaluate one of the proposed methods for measuring the air-water interface in greater detail, a gas-phase interfacial tracer method.


SET #3

a. Isotope 136Xe exhibits very high transition energy Q = 2457.8 keV, and the probability of decay by the neutrinoless channel is proportional to ~Q5. (Adapted from Belov et al. 2012)

b. Xenon (Xe) has over 30 unstable isotopes. 136Xe, which is the longest-lived with a half-life of 2 x 1021 years, undergoes double beta decay, a process that involves a nucleus releasing 2 beta particles.



a. Here, subglacial ice velocity is well correlated with moulin hydraulic head but is out of phase with that of nearby (0.3–2 kilometres away) boreholes. (Adapted from Andrews et al. 2014)

b. Our boreholes display high mean hydraulic head (close to or above overburden) and low-amplitude diurnal variability (less than 25 m or <5% of overburden).

Possible solutions

  1. a. Audience: scientists, especially those who want to be able to conduct a similar experiment. Purpose: to convey how a study was conducted.
    b. Audience: students. Purpose: to instruct on how to conduct an experiment.
  2. a. Audience: scientists, especially professionals interested in air-water interfacial areas. Purpose: to explain what hasn’t been done yet.
    b. Audience: scientists, especially professionals interested in air-water interfacial areas. Purpose: to describe how the “current study” addresses a poorly-understood topic.
  3. a. Audience: scientists who are well-versed in isotope decay and its associated terminology. Purpose: to inform about the decay properties of 136Xe.
    b. Audience: students. Purpose: teach about the decay properties of 136Xe.
  4. a. Audience: scientists interested in subglacial ice velocity. Purpose: to describe experimental results.
    b. Audience: professional glacial scientists. Purpose: to describe experimental results.

As you can see, sometimes similar-sounding information can address 2 entirely different audiences and/or purposes, while different purposes can be achieved with the same audiences in mind. The vocabulary, level of detail, and amount of explanation you use can all help tailor information to your intended audience and purpose.


Think: For your most recent writing assignment, what was your purpose? Who was your audience (other than your professor)?


Addressing your audience

Imagine that you get in a car accident. How would you tell your friends what happened? Would that be different from what you would tell your parents? What kinds of things would you say to the insurance company? Likely, the way that you tell the story and the details you include would be different depending on your audience. In scientific writing, too, who your audience is greatly impacts what you say and how you say it, even if the topic is the same.



Who is my audience?


Your audience consists of people who will most likely read a particular piece of your writing. Your audience may include:

  • Experts, who are highly familiar with the specific area or topics you discuss
  • Scientists, who may be a part of any scientific field and therefore will automatically understand the basic scientific concepts but not all of the details you discuss
  • Students, who will be reading with limited prior knowledge but are hoping to learn more.
  • The general public, who may be interested in the subject but have little to no prior knowledge of it.

Identifying your audience is before you begin writing will determine how much context and background information you need to provide, how much detail you include throughout your writing, and the formality with which you say it.

As a student learning to write scientifically, you will most likely be addressing only experts, scientists, and other students. Journal articles, research proposals, and scientific posters can be written for any or all of these audiences, so long as you understand how to modify the levels of formality and detail you use in your writing. The general public tends to read popular science articles such as those in National Geographic, so this audience will not be addressed here.



How does my audience affect the level of detail I use?


Different audiences require different amounts and kinds of detail. An expert would probably want to know the details of how results were obtained and analyzed because this would impact how they saw the research impacting their field. A scientist might require more details on the previous research that led up to your project, since they would be less familiar with the specific area of your research. A student, meanwhile, could be most interested in the fundamental scientific concepts discussed so they could better connect the research to other concepts they were learning.


Let’s compare the audiences of and details in the methods sections of lab reports and journal articles as an example:


Journal article Lab report
Audience Experts Students
Detail of Methods Instrumentation used, general methodology Safety precautions, equipment used, how to conduct procedures
Examples measurements taken using a Bohlin Gemini rheometer; “Dried cellulose was immersed in 0.1 M NaOH.” “Dried 0.4132 g cellulose under vacuum for 15 min. Added 10 mL 0.1 M NaOH, being careful to immerse all particulate.”


But how do you determine what level of detail is appropriate for each audience? To help get at the answer to this, you might want to ask yourself two questions:

  • What does your audience already know?
  • What does your audience want to do with the information?

In a journal article, your audience probably wants to know how you conducted your experiments and the results and implications of the work. In a research proposal, they want to be convinced that your research is important and worthwhile, so lots of background information and data is a key element. Your audience for a poster wants to gather a summary of your entire project in a short amount of time, so details should be chosen carefully.

In the example above, a student needs to know in great detail how to perform an experiment. An expert only needs to know what was done in enough detail to replicate the experiment; of less utility are such things as the general equipment that was used or how much of a reagent was made.


Aud-3.1: Test yourself – Biology

Based on the kinds of details used, which audience (expert, scientist, or student) do each of the following statements seem to be most addressing?

  1. Measure 140 mg ammonium sulfate into a 15-mL conical vial. Add 4.0 mL cell lysate preparation and rotate at room temperature for 30 min.
  2. The testosterone assay is based on a four-position tritium competitor and an antiserum raised against testosterone-11-BSA. Hydrolysed urine samples were extracted twice in diethyl ether prior to assay, with recoveries individually monitored by the addition of trace amounts of tritiated testosterone (Muller and Wrangham 2004).
  3. In plants, miRNAs base pair with messenger RNA targets by precise or nearly precise complementarity, and direct cleavage and destruction of the target mRNA through a mechanism involving the RNA interference machinery (adapted from Ambros 2004).
  4. MicroRNAs pair to the messages of genes that code for proteins to prevent them from allowing the synthesis of these proteins. (adapted from Ambros 2004).

Solutions – Biology

1) student; this is the kind of detailed procedural instructions that would be found in a lab manual or notebook.
2) expert; enough important detail (such as “extracted twice in diethyl ether”)  is given in scientific terms that an expert could replicate the project, but the nitty-gritty of the benchwork (like the volume of the urine samples) is left out.
3) scientist; this description of miRNAs is a little more in-depth than could probably be given to a student all at once, yet it helps more sophisticated scientists grasp the background of the project.
4) student; this is a much more surface description of miRNAs that requires only minimal knowledge of biology.

Aud-3.2: Test yourself – Chemistry

Based on the kinds of details used, which audience (expert, scientist, or student) do each of the following statements seem to be most addressing?

  1. The appropriate function of insulin-producing pancreatic β-cells is crucial for the regulation of glucose homeostasis, and its impairment leads to diabetes mellitus, the most common metabolic disorder in man (Leibiger, Leibiger, and Berggren 2008).
  2. Thermal cycling conditions were set as follows: initial denaturation step at 50°C for 2 minutes and 95°C for 10 minutes, followed by 40 cycles at 95°C for 15 seconds and 60°C for 1 minute (Mitani et al. 2009).
  3. Although the mechanisms of its antitumor effects remain unclear, it appears that cell cycle arrest and apoptosis induction via various regulatory pathways may play fundamental roles (Mitani et al. 2009).
  4. The most performing ligand architectures are based on tetra-arylporphyrins (N4), Schiff bases (N4), salens/salphens and related ligands (N2O2), substituted phenols (N2O) or complex bridged bisphenols (N4O2) (Adolph et al. 2015).

Solutions – Chemistry

1) student; this statement includes a simple explanation of what diabetes is but doesn’t go greatly into detail about the chemistry of β-cell function.
2) expert; the details of exactly how the PCR was conducted would mostly be of interest to an expert trying to replicate the experiment.
3) scientist; suggestions of possible mechanisms would help scientists better understand the direction of the field but wouldn’t necessarily help a student learn more about how the molecule functions.
4) scientist; the statement lists the types of structures that are functional but doesn’t go into detail about why they work, making it somewhat less useful for an expert.

Aud-3.3: Test yourself – Physics

Which audience (expert, scientist, or student) do each of the following statements seem to be most addressing?

  1. It describes the coherent exchange of energy between a quantized electromagnetic field and a quantum two-level system at a rate g/2π, which is observable if g is much larger than the decoherence rates κ and γ (Wallraff et al. 2004).
  2. In order to identify the sources of turbulence in astronomical systems, it is also important to determine the behavior of velocity and magnetic field correlations on larger spatial scales (adapted from McKee and Ostriker 2007).
  3. Two electrical components are in series if they are joined together at one end each; electric current flowing through the first component has nowhere to go but through the second component as well (Ratcliff 2014).
  4. Although chaotic communication experiments with electronic circuits have typically demonstrated information transmission at bandwidths of tens of kilohertz or less, the fast dynamics of optical systems offers the possibility of communication at bandwidths of hundreds of megahertz or higher (adapted from VanWiggeren and Roy 1998).

Solutions – Physics

1) expert; “g/2π” and “the decoherence rates κ and γ” are so specific that they would likely only be of interest to someone with prior knowledge of quantum physics.
2) scientist; “turbulence in astronomical systems” is somewhat specific to the area of study but is not so detailed that a non-physicist couldn’t understand it.
3) student; this a clear and simple explanation that requires no prior knowledge of physics.
4) scientist; telling us the orders of magnitude of bandwidth is necessary to understand a key difference between electronics and optics, yet the overall statement only involves fairly basic scientific concepts.

Aud-3.4: Test yourself – Geology

Which audience (expert, scientist, or student) do each of the following statements seem to be most addressing?

  1. Extracellular polymeric substances, widely produced by microbes for attachment and protection, are important in facilitating sediment trapping in cave and soil environments (adapted from Riding 2000).
  2. Sandstone composition is influenced by source rock composition, climate, relief, slope, vegetation, and characteristics of the depositional environment (adapted from Johnsson, Stallard, and Meade 1988).
  3. Sands were cemented with epoxy, and standard thin sections were stained for both potassium feldspar and plagioclase (adapted from Johnsson, Stallard, and Meade 1988).
  4. Grain surfaces of first-cycle sands from the lowland shield are typically densely covered with dissolution etch pits and are frequently deeply embayed, features that are rare on the surfaces of first-cycle sands from the elevated shield (adapted from Johnsson, Stallard, and Meade 1988).

Solutions – Geology

1) scientist; understanding this statement requires some scientific background to understand such phrases as “extracellular polymeric substances,” but none of the details require highly specific knowledge about geology.
2) student; the details used would be accessible to someone with minimal scientific background and are used to teach fundamental knowledge about sandstone.
3) scientist (or expert); this level of methodological detail would be useful to any scientist trying to better understand your project (but could also be used by someone trying to replicate the experiment).
4) expert; such detail would be of little interest or use to someone who did not already understand the implications of “first-cycle sands” and want to know extremely specific information about grain surfaces.



How does my audience affect the formality of my writing?


Tone is a quality that writers across all disciplines often struggle with. Yet it is critical to understand how to adjust the tone of your writing so that you can most effectively communicate your meaning to your audience. In scientific writing, your tone will almost always be fairly formal, which will help you maintain objectivity.


Informal Formal
Personal pronouns (e.g., “We analyzed”) Passive voice (e.g., “It was analyzed”)
Contractions (e.g., “can’t,” “won’t”) Full words (e.g., “cannot,” “will not”)
Colloquial expressions

  • a lot
  • totally
  • at the same time
  • interesting
  • look into
Academic expressions

  • many
  • completely
  • simultaneously
  • compelling
  • investigate
Wordiness Conciseness


While you want to maintain your credibility as a scientist by using formal language, you also don’t want to alienate or lost the interest of a reader who might be less familiar with your subject. Thus, your level of formality should generally increase with the expertise of your audience.


Level of formality
General public    <     Students    <    Scientists    <    Experts


Writing for scientists and experts should be very formal but can be somewhat less formal for students. The following are examples of what kinds of language are appropriate for different audiences:


Your writing Audience…….. Acceptable aspects of informality
Poster at a student symposium Scientists Personal pronouns and contractions maybe okay
Poster at a national conference Experts None
Journal article for publication Experts or scientists None
Research proposal Experts None
Textbook Students Contractions and colloquial expressions
Class handout Students Personal pronouns, contractions, and colloquialisms


Note that the exact level of formality you should adopt for a given assignment is ultimately up to your professor.


Aud-4: Practice exercise

Re-write each of the following statements to make them more formal.

  1. When I first mixed the dried cell extract into the solution, it didn’t dissolve. After I stirred it for a while, it finally did.
  2. The oscilloscope said that the frequency wasn’t above 25 Hz.
  3. DNA, or deoxyribonucleic acid, packs a lot of genetic information into a relatively tiny molecule.
  4. When the sediment collected downstream after the storm event from the week previous to the week that this study happened, buildup caused troubles for the water to flow from the stream into the main lake.

Possible solutions

  1. The dried cell extract dissolved completely after continual stirring.
  2. Using an oscilloscope, the frequency was determined to be less than 25 Hz.
  3. Genetic information is compactly stored in cells using DNA. [“DNA” usually does not have to be spelled out, as it is common knowledge.]
  4. Sediment accumulation from a storm event the week previous hindered drainage from the stream into the main lake.

Note that by using formal language, your writing will also become more concise!