rules for evaluating an investigator's research endeavor are closely guarded by a code of research ethics to which the writing and investigation must adhere; namely objectivity, subject knowledge, and professionalism. The article authored by Henderson and Evans and the subject of review is the six-sigma statistical process employed to evaluate manufacturing quality improvement.
The article was carefully scrutinized with respect to adhering to proper research formatting. A definitive evaluation was presented in terms of identifying a proper research question, need and problem, proper data analysis, and the effectiveness summary conclusions drawn. Unfortunately the article critiqued is not a true research endeavor as the authors failed to adhere to the stringent rules of conducting research investigations. The totality of the information presented is simply a reporting of what is currently taking place in a large corporation with respect to quality improvement.
The structure of a research report is simple. It is almost the same as the structure of the research itself: the problem, the methodology, the results, the conclusions, and the interpretations. The purpose of the research report is to inform readers about the problem investigated, the methods used to solve the problem, the results of the investigation, and the conclusions inferred from the results (Polit & Beck, 2004). The function of the research report is not, however, to convince the reader of the virtue of the research previously conducted. At all times the report is to be so written that the reader can reach their own conclusions as to the adequacy of the research, the validity of the reported results, and the conclusions. Research reports must strive to be succinct, objective, and crystalline. The ultimate test of an excellent research report is in its ability to be replicated by those who read it. If this criterion cannot be met then the report is inadequate in terms of knowledge transfer.
The paper presented herewith is a thorough analysis and critique of research information reported in an article entitled Successful Implementation of Six-Sigma: Benchmarking General Electric Company (Henderson and Evans, 2000). The critique will cover areas important to research facilitation including, but not limited to, methodology used, formulation of an appropriate research question, significance of reported substantive literature, research design selection, appropriateness of sample data gathering techniques, and data analysis, and importance of conclusions drawn.
Article Summary. Research endeavors must at all times adhere to the rigors of effective or best-fit research practice. Without stringent controls placed on the area of investigation no research endeavor will advance any body of knowledge. To this end all research must be finely tuned and described as to intent or purpose, phenomenon to be assessed and reported upon, and relevance and efficacy of conclusions drawn.
The present article being critiqued as to form and content was a thorough in-depth description of the six-sigma quality control process in several selected manufacturing settings. The authors presented concise and factual information as to how the six-sigma statistical tool is implemented in a manufacturing setting and what the benefits are to using such a quality control process. However, through out the entire article there was no discussion as to the drawbacks of implementing such a system in terms of analytical cost factors, time constraints, or appropriateness of statistical results achieved by utilizing a six-sigma quality improvement process. Without presenting both sides of a theory or process there exists a very strong possibility of author bias being introduced into the reported findings. This was found to be true in the concluding remarks offered by the two authors.
Although Henderson and Evans presented a thorough description of the statistical components of the six-sigma process, discussion of all that is presented is beyond the scope of this paper. Suffice it to say that the authors are very complete in their presentation of all statistical processes - from dashboards, to Kruskal-Wallace techniques, to those of ANOVA and Chi-Square. However, caution should be garnered as to the utility of the presentation with respect need. That is, if the author's purpose is to educate the reader on specific statistical processes contained within the six-sigma program then an earlier statement of purpose should have been declared (Ohlson, 1998).
Research Question(s), Objective and Research Methodology. Research when done well, albeit clinical, experimental, or historical must begin with the author presenting a well developed need for the research followed by an answerable research question. The research question is, according to Kerlinger (1964) a result of a felt need the author or authors present to the reader based upon information offered in opening statements of the published article. Contained within the opening statement must be the research investigator's definition of the type of research being conducted; i.e., descriptive, experimental, historical, philosophical, or case study. At no time though out the beginning of the manuscript was there any definitive statement as to what type of research Henderson and Evans had conducted. As such the reader is not given any direction as to what to expect in terms of what the investigators attempted to investigate from any particular research inquiry perspective. In fact the entire research report was basically a thorough description of the six-sigma statistical process used General Electric to determine a rejection level for acceptable and non-acceptable consumer products. The closest the investigators came to stating a researchable problem, or state a research methodology, is in their initial statement that the original goal of the six-sigma process is to define quality improvement as implemented by General Electric.
Although the authors, Henderson and Evans, never clearly delineated exactly what type of research they were conducting, nor did they formulate an identifiable research question, the reader can conclude on their own that what was reported was basically in the form of historical qualitative case study. Further, historical qualitative case research generally follows along the lines of identifying certain trends that exist in the concept of phenomenon being reported upon. As such the two research investigators should have formulated a research question and hypothesis along the following lines: To what extent does there exist an increased or decreased use of the six-sigma quality standards process in the manufacturing by General Electric? In addition, to what extent is the six-sigma statistical process a viable statistical tool for determining quality standards in manufacturing visa via quality improvement for General Electric? The closest the investigators came to stating a researchable problem is in their initial statement that the original goal of the six-sigma process is to define quality improvement. As the research investigation being reported upon is a case study situation the research investigators were not obligated to follow the research question with a testable null hypothesis such as is required in experimental of descriptive research studies.
Research Methodology, Design and Data Gathering Techniques. Not having set forth the type of research being conducted or stating any discernable research question the authors failed also to inform the reader as to the type of research methodology/design being used to investigate the phenomenon under examination. To the unassuming reader that which was presented by Henderson and Evans is nothing more that a presentation of existing six-sigma information amassed by General Electric itself. In fact, had there not been author identification in terms of where each author is employed one would conclude that the information presented in the article was an internal corporate "report" commissioned by General Electric itself for in-house use. The two authors could easily have explained to the reader in their opening statements that the information contained within the article is strictly a review of General Electric's use of the six-sigma statistical quality improvement process. Further, when research investigators embark upon an endeavor to explain a certain concept or process to the reader there exists an obligation on the part of the author(s) to inform the reader as to how information is being gathered (design); i.e., original testing or experimentation, historical literature review, case study analysis, or opinion survey. At no time did Henderson and Evans alert the reader as to how the material was collected. The reader was simply presented with a great deal of information and left to derive their own conclusions.
Limitations. A great deal of difficulty arises when attempting to critique a research endeavor that has not been properly defined and/or executed. Any researcher must be fervently unbiased when presenting information upon which is being reported. There must exist complete fairness in reporting the positives and negatives of a research investigation, regardless of personal wishes. With respect to the Henderson and Evans endeavor a great deal of effort was put forth to reinforce the use of the six-sigma process within General Electric. At no time was there any mention of any limitation or problem General Electric encountered in the implementation and continued use of the six-sigma quality improvement process. In addition, the authors did not present to the reader information necessary to investigate other corporations who have employed the six-sigma process in order to draw comparisons in terms of success or non-success.