Lesson: Building Paragraphs

The way you organize the information within paragraphs is central to a successful paper describing your science research. You want the reader to be able to quickly access the information with full understanding. To do this, you need to place sentences in a very logical order and pay careful attention to how one sentence “flows” into the next. Here are some questions to think about:

  • What are the characteristics of a well-written paragraph in science writing?
  • How long should a paragraph be?
  • How do you organize the ideas/sentences within a paragraph?
  • What else should you consider when writing or revising a paragraph?

 

Part 1: Characteristics of a Well-Written Paragraph

  • Each paragraph contains one controlling idea, usually one of the following:
    • main idea with supporting explanation and details
    • main idea divided into key categories
    • one step in a process
  • Every paragraph should be easy for the reader to navigate and understand.
  • The first sentence of a paragraph is usually a "topic sentence" that introduces the main idea.
  • The order of sentences must be logical, but this will vary depending on the topic/purpose of the paragraph.

 

Part 2: Paragraph Length
Usually, the length of a paragraph is a topic sentence followed by 3-5 sentences but can vary between 1 and 8 sentences (Wallwork, 2011). Each sentence usually has one or two clauses. Avoid including multiple ideas in one sentence unless the results can be easily read.

 

Part 3: Organization of Sentences within a Paragraph
Sentences within a paragraph must be carefully organized according to a logical relationship between ideas. Common patterns for doing this in scientific writing include the following:

  • moving from general ideas to more specific ideas
  • introducing one theme and then dividing this into subthemes
  • chronological order

Analyze the following example paragraphs to decide how the information is organized.

1.   What organization pattern best describes this paragraph?

Reaching populations in need continues to prove challenging as we at the Bill & Melinda Gates Foundation frequently observe working with partners to fulfill our mission. The challenges point to a high degree of complexity in the interplay of stakeholders in the global regulatory and delivery systems. The key stakeholders include global and regional pharmaceutical companies, non-governmental organizations, national medical product regulatory agencies, ministries of health and others who make product utilization recommendations. In particular, regulatory and procurement requirements vary widely between countries, creating a system with many inefficiencies and redundancies, only a few of which have been adequately documented.*

Answer: It moves from a general idea to consecutively more specific ideas.

2.   What organization pattern best describes this paragraph?      

Twenty field teams consisting of one enumerator, one field worker, and one person trained for blood sample collection were equipped with high resolution maps and a handheld GPS receiver (GPSMAP 62s; Garmin International) with preloaded waypoints for 16 randomly selected compounds and cell boundaries. Compounds were eligible for sampling if at least one adult and one child (< 15 y) were permanent residents (defined as sleeping regularly in the structure) and written informed consent was obtained. If a selected compound did not satisfy these criteria, the nearest non-selected inhabited compound was selected as a replacement. Participating individuals in the community survey were screened by axillary thermometer for fever, and those with fever were tested by RDT (HRP-2, Paracheck, Orchid Biomedical Systems) for on-site malaria diagnosis and treatment with artemether-lumefantrine (AL) (Coartem, Novartis) if RDT positive. Febrile individuals who were RDT negative, pregnant, or below 6 mo of age were accompanied to a local health facility for a full clinical assessment and treatment.*

Answer: Chronological order is used to describe the steps in this part of the data collection.

3.   What organization pattern(s) best describes this paragraph?

We identified several potential root causes of this time spread. First, as mentioned earlier, large multi-national manufacturers typically did not prioritize early registration and introduction of their novel products into low-income countries. This is due to limited commercial potential in most of those countries. Additionally, varying requirements and legislative frameworks in low-income countries limit the ability of manufacturers to submit a single dossier concurrently to those countries. The enormous resources required to prepare unique submissions for each country and respond to questions from each individual NRA may have exacerbated this spread. As a result, some countries experience long waits before they even receive application dossiers for review.*

Answer: A theme is introduced and then divided into subthemes. In addition, each subtheme moves from general information to more specific information.

 

Part 4: Creating Flow Between Sentences in a Paragraph
The reader should be able to move easily from one sentence to the next, without stopping to wonder how the ideas connect. We often refer to this smooth relationship between sentences as "flow," In scientific writing, flow is usually created through the following three techniques (adapted from Swales & Feak, 2012): 1) placement within sentences of “old” and “new” information, 2) use of determiners and demonstratives, and 3) use of sentence connectors. See below for explanations. 

“Old” and “new” information placement within a sentence
Place a reference to “old” information (which has already been presented in a preceding sentence) before introducing “new” information. This, along with logical organization of ideas, is the best way to create flow.

Examples

Mosquito exposure was monitored in three interventions and three control clusters; in each of the clusters, four compounds within hotspot boundaries and eight compounds located in the evaluation zone were randomly selected for monitoring.**

Parasite prevalence in the malaria hotspots and in the evaluation zones surrounding the malaria hotspots was determined based on nPCR parasite detection in three surveys conductedin March– April (baseline), June– July (8 wk post-intervention), and August– September 2012 (16 wk post-intervention). Each survey took approximately 2 wk to complete.**

Mosquito breeding site productivity was assessed in 15 sites per intervention hotspot ( n = 75 in total). Of the sites sampled prior to larviciding, 45% (34/75) were positive, of which 12 had late-stage larvae and/or pupae.**

Malaria transmission in the area is seasonal and associated with seasonal rains that typically peak between March and June and between October and November. Transmission intensity in the study area is generally low… .**

Determiners and demonstratives
When appropriate, use demonstrative adjectives "this" or "these" or the determiner "such" to indicate previously mentioned information.

Examples

Mosquito densities are highest in hotspots, and individuals in hotspots may amplify transmission by transmitting malaria parasites to a large number of mosquitoes that fuel transmission to wider areas. This amplified transmission can lead to 1.5- to 4-fold increases in the basic reproductive number of malaria parasites.**

We hypothesized that combined malaria control interventions targeted at hotspots could reduce malaria transmission not only inside these hotspots but also in adjacent areas. To test this, we identified hotspots of malaria transmission in a low endemic area in the western Kenyan highlands, and conducted a cluster-randomized controlled trial to measure the effect of hotspot-targeted interventions in evaluation zones surrounding malaria hotspots.**

Successful targeting of malaria control efforts to hotspots may therefore be a highly efficient method to reduce malaria transmission in a wider area and achieve community protection by eliminating transmission in a relatively small geographical area. Such targeted interventions are likely to become increasingly important tools in malaria elimination efforts once transmission in an area has decreased but is maintained in hotspots of malaria transmission.**

Sentence connectors
If necessary, and only if necessary, add a sentence connector such as “however” or “for example." Use these sparingly: Too many sentence connectors can actually break up the flow.

Examples

Our decision to monitor the incidence of malaria cases passively was based on the low efficiency of active monitoring of infections in low endemic settings, although we acknowledge that PCD leads to a considerable loss in power compared to active case detection. As a consequence, our approach will have resulted in an unknown number of malaria episodes that were missed due to health care seeking behavior or other factors.**

There are several possible reasons for the apparent failure to completely eliminate malaria transmission inside hotspots and the undetectable impact in the evaluation zones surrounding targeted hotspots. First, it is possible that our interventions did not clear vector populations or prevent human– vector contact inside hotspots to the extent that is required to interrupt local transmission.**

Our trial included a total of ten clusters during a single season and was therefore not powered to detect subtle effects of hotspot-targeted interventions nor designed to detect effects of interventions that become apparent over multiple transmission seasons. Furthermore, we saw a higher than expected level of inter-cluster variation.**

This amplified transmission can lead to 1.5- to 4-fold increases in the basic reproductive number of malaria parasites. Successful targeting of malaria control efforts to hotspots may therefore be a highly efficient method to reduce malaria transmission in a wider area and achieve community protection by eliminating transmission in a relatively small geographical area.**

 

Swales, J., & Feak, C. (2012). Academic writing for graduate students: Essential skills and tasks (3rd ed.). Ann Arbor, MI: The University of Michigan Press.

Wallwork, A. (2016). English for writing research papers. New York: Springer.

 

* These examples come from the following reading:
Ahonkhai, V., Martins, S.F., Portet, A., Lumpkin, M., & Hartman, D. (2016). Speeding access to vaccines and medicines in low- and middle-income countries: A case for change and a framework for optimized product market authorization. PLoS One 11(11), 1-12. http://dx.doi.org/10.1371/journal.pone.0166515

** These examples come from the following reading:
Bousema, T., Stresman, G., Baidjoe, A. Y., Bradley, J., Knight, P., Stone, W. et al. (2016). The impact of hotspot-targeted interventions on malaria transmission in Rachuonyo South District in the Western Kenyan Highlands: A cluster-randomized controlled trial. PLoS One 13(4), 1-25. http://dx.doi.org/10.1371/journal.pmed.1001993