The Matrix Method

Garrard J. Health sciences literature review made easy: the matrix method. 2nd ed. Sudbury (MA): Jones and Bartlett; 2007.

No, we're not talking about ways to solve the Schrödinger Equation. I ordered this book recently for my library on the strength of a 5-star recommendation from Doody's, and I wasn't disappointed. I read it through this morning, delighted by its competent discussion on organizing one's research. As the reviews say, it is easy-to-read and practical, primarily designed for the student, but of interest to anyone who does systematic research. Judith Garrard teaches at the School of Public Health, University of Minnesota. She makes use of her long experience guiding student research to describe what she calls the Matrix Method for reviewing and tracking scientific literature.

Avoiding the longueurs of most treatises I have seen of this type, Garrard introduces her method in simple and elastic prose: "a plan for gathering materials to be included in a review of the literature, systematically analyzing the information and writing a synthesis, and organizing and filing documents, notes, and other materials in one of four sections ... in a Lit Review Book during and after completion of the review" (p. 164).

The four sections are:

1. Paper Trail: the record of the search process used to identify relevant materials;
2. Documents Section: all the actual documents gathered for the literature review;
   
3. Review Matrix: data arranged in columns and rows in order to abstract selected information about each document;
4. Synthesis: a written synthesis of one's critical review of the literature based on the information abstracted in the Review Matrix.
   

The results of this labour are collected and put into what Garrard calls a "Lit Review Book," essentially a large binder with the four sections outlined above. She does not fuss about format, however, and leaves it to the researcher how he or she will create the "book," whether on paper or with a computer.

The Review Matrix is the heart of the Matrix Method. Its purpose is to provide a standard structure for creating order out of the welter of information from the literature. It is essentially a large spreadsheet. Each row is a journal article, book chapter, etc. The columns represent categories for breaking down the contents of documents into analyzable pieces, e.g., year of publication, purpose, methodological design, variables, number of subjects, instrument, special notes.

There are distinct advantages to this kind of abstracting process, provided that the researcher has done a thorough job of collecting the most relevant research papers on a subject (and Garrard frequently recommends consulting a librarian in the research process). As she puts it,

In the first place, you learn something about the sociology of the subject you are reviewing [i.e., who the important authors are, which studies are cited repeatedly, etc.]. Second, by taking apart and abstracting each study using the same set of topics, you are better able to state questions of your own. Finally, you begin to have a better sense of what is missing and areas in which new research is needed (p. 120).

In other words, the matrix provides a convenient format that allows for rapid comparison of vital aspects of each document, depending on the researcher's particular needs. The result is a comprehensive overview and synthesis of what has been written on one's chosen topic. You "own" the literature.

Complementing Garrard's method, the Matrix Indexing System offers a common-sense way of using reference management software to organize references found in various databases. The author is a firm believer in chronologically arranging physical documents in three-ring binders or folders and pointing to them using location labels in individual citations. Storing everything in the Lit Review Book, in combination with the bibliographic control afforded by the reference database, is the best way of keeping track of a research project over time. Visual examples and a single case study are woven throughout the text to help us see how this method can be applied in real-life research.

I have benefited from this book and will soon be creating my first Lit Review Book. The Matrix Method will also help me when I am assisting patrons who inquire about literature reviews. Highly recommended for any health library.