BSCI 1510L Literature and Stats Guide: 3 Style of scientific writing

Scientific writing differs in several ways from writing in the popular press.  It is focused exclusively on a description of the methods, results, and relevance of a particular experiment or series of experiments.  Extraneous comments, speculation, and humor are avoided.  It is considerably more "dense" than typical writing in the sense that what is to be communicated is reduced to the clearest and most succinct wording.  Generally passive voice is used (e.g. "The samples were mixed…" rather than "We mixed the samples…").  Citations within the text refer to previous work related to the particular item being discussed.  Finally, the text is generally divided into standardized sections, each with a particular purpose.  The third section of this Guide will describe the details that you need to know to be a successful scientific writer.

It is often challenging for students to know what details to include in a research paper, because this intuition comes from reading hundreds of published papers. The appropriate level of detail depends on the subject matter and scientific field, the preferred style of a particular journal, and the complexity of the overall procedure. Generally, methods sections should be written so that a scientist who is familiar with your research topic, but does not know the details of your specific experiment, could reproduce your procedure. When professors write protocols for their classes, they often include detailed reminders (wear gloves, use a blue 1.5 mL tube, etc.) because they’re writing for students. If you read through published research papers, you'll notice that these details are omitted, and that their methods are much more concise.

As an example, here are details that (typically) do not need to be described in a biology methods section:

• the size/ color of the microcentrifuge tubes or other equipment – descriptions that do not impact the study results can be left out.
• Repetitive use of transition words (then, after that, finally, first of all). It is assumed that methods are written chronologically, so unless you are specifying a specific waiting period between steps, repetitive transition words just take up unnecessary space.
• Assumed steps were taken to clean or sterilize equipment and reagents. Though of course you should wash your hands, wear gloves, wipe down your bench space, and sterilize reagents for biology labs, this usually doesn’t need to be explained in a methods section, unless it directly relates to the experimental variables.

Student methods excerpt:

First of all, measures were taken to prepare a sterile workspace prior to transformation. Tubes and reagents were autoclaved. Then, a tube of reporter plasmid DNA was mixed. Then, the plasmid DNA sample was added to eight 1.5 mL blue microcentrifuge tubes. Then, each tube was vortexed. The tubes were incubated for 25 min at 30 degrees Celsius. The tubes were then incubated at 42 degrees Celsius for 20 min. The cells were spun for 1 min at 3500 RPM, and the supernatant was removed. The pellets were added to sterile water and mixed up and down with a pipetter.

Rewrite to eliminate repetition and unnecessary language:

Reporter plasmid pA10 DNA (10 mg/mL) was incubated at 30°C for 25 minutes and heat shocked at 42°C for 20 minutes. Pellets were centrifuged (3500 RPM, 1 min) and resuspended in sterile water.

The rewrite conveys the important information necessary for repeating the procedure (plasmid name, incubation time and temperature), without including unnecessary information (size and color of tubes, cleaning of equipment) that could be safely assumed by the reader. It also employs grammatically complex sentences to eliminate unnecessary language and repetitive sentence structures. Notice how some information is conveyed parenthetically; this can be a useful grammatical tool for listing ingredients or concentrations.