How to write an abstract: Avoiding six common mistakes

By Katherine L. Molnar-Kimber, Ph.D.

Learning how to write an abstract for a meeting, scientific paper, case report, white paper, review, or medical article involves avoiding these 6 common mistakes that I've observed in substantive editing (rewriting) of manuscripts:

Mistake #1. Authors do not provide a brief background that explains the importance of the unresolved problem which has been investigated and described in the abstract.

Excellent abstracts include a clear, concise synopsis of the current status in the field, statement of the issue, and the significance of solving the controversy.

In the example, the first two sentences provide the current status of the field and the rationale for the study.

Mistake #2. The length or format does not conform to the journal’s or meeting’s guidelines.

Each scientific journal or meeting gives the length and format for submitting an abstract.

A few journals require an abstract of 150 words or less. Most journals allow abstracts of 200 or 250 words, and a few journals allow 400 words in the abstract.

The format varies from an unstructured abstract with a blank space to a structured abstract with 4-5 subheadings such as Background, Methods, Results, Conclusions. Abstracts on clinical studies often have the subheadings: Objective, Patients, Methods, Results, Conclusions, Implications.

Regardless, abstracts should address each of these points in a concise, detailed manner.

Mistake #3. Hypothesis and rationale are not evident.

A rationale for investigating the studies is essential.

Although the hypothesis was not explicitly stated in this example, the rationale was stated ("Therefore, strategies to enhance the efficacy of this treatment were investigated.")

Mistake #4. Methods section are written in the present tense.

Methods section should describe how the authors had performed the studies and analyses, and thus be written in past tense. Because of the space constraints, Methods section may provide an overview. Abstracts of clinical studies include the essential inclusion and exclusion criteria of the patient population, control subjects, the primary endpoint and, if possible, the secondary endpoints.

In the example, the methods are summarized in the following 2 sentences:

"We determined the oncolytic activity of HSV-1716 in NCI-H460 cells in combination with each of four chemotherapeutic agents: mitomycin C (MMC), cis-platinum II (cis-DDP), methotrexate (MTX), or doxorubicin (ADR). Isobologram analysis was performed to evaluate the interaction between the viral and chemotherapeutic agents. "

Mistake #5. Results section used undefined terms like “dramatic”.

Data should be analyzed with the appropriate statistical programs based on the type of variable. Results section should state whether the data from experimental conditions and controls were significantly different.

If the effect in different cell lines are distinct, then both sets of data should be presented if space permits.

For example, "The oncolytic effect of HSV-1716 in combination with MMC was synergistic in two of five NSCLC cell lines. In the other three cell lines, the combined effect appeared additive. No antagonism was observed."

Results that do not show a significant difference can also be published.

For example, "The synergistic dose of MMC neither augmented nor inhibited viral replication in vitro and HSV-1716 infection did not upregulate DT-diaphorase, which is the primary enzyme responsible for MMC activation."

Mistake #6. Conclusions are not fully supported by the data or literature.

The conclusions should be based on the results and discussion sections of the manuscript or poster. Implications of the research should be included.

In this example, conclusions reflected all the presented data and not just the synergistic combinations.

Note that abstracts for successful NIH grants follow a distinct structure that highlights their proposed research.

How may I help you write or edit an abstract, manuscript, white paper, review, poster, case report, grant proposal, or meeting summary?

I would be happy to discuss the editing or writing of your abstract, manuscript, review, white paper, case report, or poster. Work samples include some of my published reviews, web pages, monographs, CME, and 50+ scientific and clinical articles.
More than 50 different journals include my edited, rewritten (substantive edited), or written scientific and clinical articles.

Abstract Example from Journal article

This abstract is from Toyoizumi et al, 1999 published in Hum Gene Therapy.

A replication-selective herpes simplex virus type 1 ICP34.5 mutant (HSV-1716) has shown efficacy both in vitro and in vivo against human non-small cell lung cancer (NSCLC) cell lines, but complete eradication of tumor has not been accomplished with a single viral treatment in our murine xenograft models. Therefore, strategies to enhance the efficacy of this treatment were investigated. We determined the oncolytic activity of HSV-1716 in NCI-H460 cells in combination with each of four chemotherapeutic agents: mitomycin C (MMC), cis-platinum II (cis-DDP), methotrexate (MTX), or doxorubicin (ADR). Isobologram analysis was performed to evaluate the interaction between the viral and chemotherapeutic agents. The oncolytic effect of HSV-1716 in combination with MMC was synergistic in two of five NSCLC cell lines. In the other three cell lines, the combined effect appeared additive. No antagonism was observed. The in vivo effect of this combination was then examined in a murine xenograft model. NCI-H460 flank tumors were directly injected with HSV-1716 (4 x 10E6 PFU) followed by intravenous MMC administration (0.17 mg/kg) 24 hr later. After 3 weeks, the mean tumor weight in the combined treatment group was significantly less than either individual treatment in an additive manner. The synergistic dose of MMC neither augmented nor inhibited viral replication in vitro and HSV-1716 infection did not upregulate DT-diaphorase, which is the primary enzyme responsible for MMC activation. In summary, the combination of HSV-1716 with common chemotherapeutic agents may augment the effect of HSV-based therapy in the treatment of NSCLC.