While
marking a set of 127 student papers each containing a summary for “formative”
feedback, I realised they need more guidance. The most common comment I made
was to tell them to remove “I”, “me”, “my” from this type of writing. That part
is easy to solve. The structure and content of a good abstract is more difficult.
I
have written previously about this, but there is still more to go.
What is
needed in a good scientific summary or abstract? This varies. At the
undergraduate level abstracts usually need context and the more routine the
analysis, the more important the presentation of the context. Within the set of
papers I marked, many students wanted to measure things like fluoride, or
sodium, or potassium. They selected a sample to analyse, but rarely indicated
why. Consider cocoa. It turns out that cocoa contains potassium and is one of the richest dietary sources known. An assignment covering this topic should begin with
something about potassium and cocoa. Potassium is a key element of diet and essential to
maintaining a proper electrolyte balance. Many diets contain excessive sodium
and less potassium. Cocoa powder has been reported to contain up to
4.5% potassium.
Does this context
raise your interest more than a discussion of the operation of a high performance liquid chromatography column? Context will engage your reader more than will a typical
approach which might be like this: “This experiment will measure fluoride with an ion selective electrode machine. A set of standards will be prepared...” Somewhere
toward the end a sample will be mentioned, but the reader has lost interest. Those still
reading are likely wondering, to quote my PhD supervisor, “who the hell cares?”
(Read properly that should be yelled using a strong Texas accent.)
Having
established the context, your reader will be ready for more. When you continue,
explain the study’s goal of sampling commercially available cocoa powders and
measuring potassium content using flame photometry (or ion chromatography, or
inductively coupled plasma atomic emission spectroscopy, or...). Your audience
is prepared.
Finish an
abstract with the results and a conclusion. If you do this well, your
reader will know the what, why, and how of your study as well as the results.
Let’s see
how this fits together.
Abstract: Potassium
is a required nutrient and essential for maintaining a proper electrolyte
balance. Many diets contain excessive sodium and insufficient potassium leading to a need to monitor dietary intake of these elements. Cocoa powder
is one of the richest sources of potassium containing up to 4.5% by weight, however, little is known about
variability between commercially available brands. This project sampled commercially
available cocoa powders and assessed the potassium content using flame
photometry following a dry ash procedure. The samples contained between 1.03%
and 1.32% K by weight. Replicate analyses indicated the precision of the method
was ±0.04% indicating significant differences in potassium content between
brands. These results confirmed that, despite the observed variability between
brands, cocoa powder is an excellent source of potassium.
Note: The study and
results provided are fictitious. Interested readers wanting to know more about
potassium in cocoa powder should go here.
