Comparing Varying Types of Research Literature
One of the more confusing aspects of research literature is the many forms it can take. These different types depend on numerous factors including data size, data type, research approach, scope and objective - to name just a few. Additionally, these elements are rarely used in a vacuum, so theoretically any number of combinations and variations of these factors are possible.
The information below strives to give a broad idea how the most common types of research literature differ from the other. It would be pure hubris to claim that this is in anyway a comprehensive overview, but it hopefully will provide a basis in understanding research types.
The seven types of research literature addressed here are:
- Research Articles
- Review Articles
- Systematic Reviews
- Qualitative Research
- Quantitative Research
- Meta- Synthesis
These type of articles are a write-up of a single, relatively small experiment and/or study. Generally a specific phenomenon is studied, a discovery is made and then test and from these results a hypothesis is formed. The following citation is an example of a research article:
Evaluation of Extended-Release Pancreatic Enzyme to Dissolve a Clog. Arriola TAD; Hatashima A; Klang MG; Nutrition in Clinical Practice, 2010 Oct; 25 (5): 563-4
Although research articles may form the "lowest" tier of evidence (at least until the studies are repeated) they do serve as the basic building blocks for all other types of research literature.
Review articles quite simply are a summary, or information gathered on a single research topic from a a variety of sources. The review article will often sum-up and evaluate the collected information to form or back-up a given theory and/or argument. The relative validity or strength of a review article depends largely on the amount of data gathered beforehand. A good example of a review article is:
Nasogastric tubes: an historical context; Phillips NM; MEDSURG Nursing, 2006 Apr; 15 (2): 84-8
Systematic reviews are similar to review articles in that they serve as an overview of topic-related data; however, there are significant differences between the two. First of all systematic reviews tend to be more exhaustive during the data gathering process. Additionally the collected information is rigorously
evaluated for quality and subjected to precise statistical methodologies. Finally the results are based on clear, objective conclusion - generally resulting from the application of statistical tools mentioned above. An example of a systematic review is:
Gastrostomy feeding versus oral feeding alone for children with cerebral palsy. Gillian Sleigh, Peter B Sullivan, Adrian G Thomas. May 2010.
Qualitative Research and Quantitative Research:
The next types of research are probably best illustrated by comparing and contrasting the two. Although these two types of research are diametrically opposed to one another they both share the common goal of being comprehensive. On the other hand the scope and aim of both are on opposite sides of the spectrum.
Qualitative research is sometimes referred to "soft" research, because it tends to deal in relative intangibles rather than quantitative research which centers on numbers and statistical evidence.
Collecting qualitative data includes such devices as interviews, observation and subjective, human interpretation of events. Generally this data is represented by words and objects, and it is the researchers themselves who serve as the primary information collector. Qualitative data tends toward the subjective. Finally when the data is gathered what is sought are patterns and/or themes - the research objectives are ones of description, exploration and discovery.
In contrast, quantitative data is centers around numbers and statistics gathered by validated, structured tools such as surveys and questionnaires. These pre-designed statistical gathering tools are the primary data gathering instruments, collecting information that is largely objective and measurable. Analysis of quantitative data identifies statistical relations, and studies of these kind focus on description, exploration and prediction. An example of each type of research studies is included below:
Evaluation of five search strategies in retrieving qualitative patient-reported electronic data on the impact of pressure ulcers on quality of life. Gorecki CA; Brown JM; Briggs M; Nixon J; Journal of Advanced Nursing, 2010 Mar; 66 (3): 645-52 (journal article - research)
Quantitative estimation of exudate volume for full-thickness pressure ulcers: the ESTimation method. Journal of Wound Care, 2011 Oct; 20 (10): 453-63
Meta-Synthesis and Meta-Analysis:
Like qualitative and quantitative research, it is probably easiest to describe a meta-synthesis and meta-analysis by looking at them side-by-side. In fact both types of these articles are the results of the types of research mentioned above. Again, while each is different in content they are similar in approach. The overall goal is to be as thorough as possible, and thus the most comprehensive and reliable data on a given topic available.
A meta-synthesis, quite simply, is a comprehensive gathering of qualitative research on a given topic - providing a more subjective overview of a given topic - while a meta-analysis employs statistics to organize and evaluate collected information numerically.
An example of each type of article is listed below:
Experiences of Kidney Failure: A Qualitative Meta-Synthesis; Makaroff, Kara L. Schick; Nephrology Nursing Journal, 2012 Jan-Feb; 39 (1): 21-80
The braden scale cannot be used alone for assessing pressure ulcer risk in surgical patients: a meta-analysis. Chen, Hong-Lin; Liu, Peng; He, Wei; Ostomy Wound Management, 2012 Feb; 58 (2): 34-6, 38-40
Obviously this article only represents the tip of the iceberg of research methods, approaches and literature. For further information please feel free to contact the Biomedical Library for more information.