Understanding a Medical Abstract

An abstract summarizes significant aspects of a study, making it easier for users to understand its key findings. Abstracts published in medical journals are generally featured at the beginning of the research paper. At scientific meetings, abstracts also act as the primary mode of communication. While most abstracts are meant for medical and scientific professionals, an increasing number of patients and their family members are reading medical abstracts these days in order to learn more about cancer and treatment options. As opposed to finding journal articles, it is a lot easier to search online for abstracts. Most of these are usually available free of charge.

An abstract usually contains the following sections:

The primary objective or purpose to help explain why the study was conducted
Methods used that explain the following components:
- The kind of study that was carried out, for example - a phase II clinical trial
- The form of cancer and its stage that study participants were diagnosed with, for example - stage I lung cancer
- Other details about study participants, for example - gender and age
- The overall quantum and frequency of treatment administered (in case the treatment was in the testing phase)
- What were the outcomes, for example - tumor shrinkage, survival, side effects of treatment, or quality of life? How did these help achieve the goals of the study?
  - In case it was not a treatment study, other outcomes such as the total number of new cases of cancer or the total number of patients affected by a particular side-effect can also be included
Results that summarize information and data gathered from each study participant, as related to the key findings of the research study
Conclusions that explain the results in context of the objectives of the research study (for instance, were goals achieved) and includes them in the larger perspective of cancer knowledge

How to find abstracts

Mesothelioma Web keeps up with research and we often reprint abstracts relevant to treatment of mesothelioma. For general scientific abstracts, including medical ones, a good search engine is www.scirus.com. For cancer abstracts and published articles, one can search the Journal of Clinical Oncology, a medical journal published by the American Society of Clinical Oncology (ASCO). You can search by author name, keyword, topic, or year of publication. You can go through the abstracts and also the table of contents of each issue. Only those articles that are more than one year old can be accessed free of charge.

You can also look into the abstracts database of ASCO, which features cancer research from scientific meetings conducted by ASCO (for instance, ASCO's Annual Meeting, Genitourinary Cancers Symposia, Gastrointestinal Cancers Symposia, Prostate Cancer Symposia and Breast Cancer Symposia). Unlike abstracts presented in journal articles, the data and information given in meeting abstracts usually does not come with an entire journal article. Meeting abstracts generally contain early, unpublished data (for instance, a 2nd year evaluation of a five-year long clinical trial). As such, you need to be careful while interpreting information provided in meeting abstracts. Although final results are published at a later date in many cases (for example large clinical trials), this is not always applicable.

One can also search PubMed to find cancer-related abstracts and articles. The National Library of Medicine offers the PubMed service that contains a huge database of over 16 million citations sourced from several different medical and science journals. You can search by author or journal name or by topic. It may be a challenge to use this database because it stores articles on many other health-related topics apart from cancer. However, you can limit your search to cancer related topics by going to PubMed home page and using the "Special Queries" link. For the search to be effective, users may have to use medical or scientific terms in place of generalized words (for instance, renal cancer carcinoma instead of kidney cancer). However, PubMed features a translation tool that converts the most generic cancer terms into suitable scientific terms.

Types of medical studies published in abstracts

A medical abstract can encompass a variety of medical studies.

Epidemiologic studies analyze factors that potentially affect public health. The main objective is to identify risk factors associated with a specific disease, for example linking tobacco consumption with lung cancer. These studies also focus on identifying the best treatment for cancer in case there are several different options. Epidemiologic studies have several subtypes, the most common being case-control, cohort, and case-series studies.
Case-control studies carry out a comparison analysis involving two groups of individuals, for example, the group with cancer patients (the case) and the normal group (the control). Scientists examine genetic or lifestyle differences between the groups to understand why one group has cancer while the other remains cancer free. These studies are conducted retrospectively, implying that the event being studies has already occurred.
Cohort studies can be termed as prospective (the event is yet to happen). In these studies, a group of individuals is monitored for a long time and any new cancer cases are recorded. Usually, the objective is to determine whether specific supplements or vitamins can help prevent cancer. These studies are also used to identify risk factors related to cancer, for example, linking hormone replacement therapy with breast cancer risks.
Case-series studies present the compilation of detailed information on the diagnosis and treatment history of a patient. This detailed description is known as case reports. If a larger number of patients are administered similar treatment, the individual case report may be compiled together to create a case series. The compiled information can have the patient's gender, age, diagnosis, treatment procedure, response to treatment and the subsequent follow-up care. Outcomes recorded from these studies describe patients' experiences as applicable within a specific population. Treatment options should not be derived based on case-series studies that may illustrate both case-control and cohort studies.
A clinical trial is a research study (medical or health-related) involving patients which is used to evaluate the effectiveness or safety of a new treatment protocol or prevention method. It can also observe events and occurrences, similar to what is done in many epidemiologic studies.
A meta-analysis summarizes results derived from several different studies based on the same topic. These studies can identify trends which normally may not become evident in smaller studies. However, if the individual studies are not done properly, the meta-analysis results may turn out to be inaccurate. In addition, only published research studies are considered for the analysis, implying that only limited amount of data has been used. Studies (pertaining to the same topic) that may be relatively less significant may not have been published, and hence will not be covered during the analysis.

Evaluating the information

It can be difficult to evaluate information provided in an abstract. Here are some tips that may help:

Look for specific details such as where was the study published and whether a peer-review process was used to review publication submissions meant for the journal. Results from peer-reviewed studies are more reliable since review is done by external researchers (those not involved directly with the study). It implies that study design and methods have been reviewed properly and the researchers agree that results are significant and need to be published.
Find out the duration of the study and the total number of individuals involved. A study will be more reliable if same results are recorded in many individuals over a long period of time. However, there are exceptions such as studies involving rare forms of cancer or those with a poor prognosis, i.e. probability of recovery. In such cases, there may not be enough individuals for doctors to carry out their study. In addition, it may be necessary that some clinical trials be of shorter durations. For example, treatment clinical trials are often shorter than cancer prevention trials.
Find out if the study contradicts or supports information already available. Entirely new results may appear significant, but they need to be validated by other researchers if they are to be accepted as facts by the medical community. Review articles referred to as "systematic reviews" can be very useful. Even though they do not usually relate to new research, they examine and derive conclusions from all available published research.
Be watchful of conclusions that tend to overstate the results. Each study is just a small piece of a much larger research puzzle and it is rare that medical practice will change based on results of a single study.
Do not discontinue or change medication based on information you may find in abstracts. If you come across something new in the abstracts, you should discuss the same with your doctor.

Sources of information on this page: ASCO