O'Hanlon-Rose (2011:1) suggested that the purpose of research design and methodology, is to “ensure that the evidence obtained enables one to answer the initial question as unambiguously as possible”. Kumar (2011:95) stated that research design has two main functions. The first relates to the identification or development of procedures and logistical arrangements necessary to undertake a research study. Secondly, research design ensures that the quality conformance aspects of the research undertaking in respect of the research validity, objectivity and accuracy is ensured or guaranteed.
Bryman and Bell (2011) stated that research design essentially comprises five different types and are shown in Figure 3.5
Figure 3.5: Principal Research Design Typologies
Source: Adapted from Bryman and Bell (2011)
A discussion of the variations in research design is shown in Figure 3.5. It will further be examined and presented in the following subsections.
3.5.1 Experimental research design
Bryman and Bell (2011:45) stated that the fundamental premise of this research design involves the experimental manipulation of the independent variable. The dependent variable is measured before and after the experimental manipulation in
Research Design Experimental Case Study Cross Sectional Longitudinal Comparative
order to conduct a before-and-after analysis. This in essence allows the researcher to feel confident that any variation or difference between the two groups is attributable to the manipulation of the independent variable. Cohen, Manion and Morrison (2007:272) concurred and added that the issue of causality needs to be considered and that once this has been achieved, the applicable outcomes can be explained. Several researchers (Gay 1992; Christensen, Johnson & Turner 2015) posited that the experimental method is the only method of research that can effectively test the hypotheses concerning cause-and-effect relationships.
Furthermore, it is argued that the experimental method can be regarded as being the most valid approach to the solution of educational problems, both practical and theoretical and to the advancement of education as a science. Bryman and Bell (2011:52) stated that the main reason for introducing an “experiment” based research design is because it is considered to be the predominant yardstick against which quantitative based research is measured or judged
In order to provide a more compelling argument toward the use and application of the experimental method, Gay (1992:298) identified the key perceived features of this approach as follows:
(i) Empirical observations from experiments provide the strongest bases for inferring causal relationships;
(ii) The researcher manipulates the independent variable directly while manipulating all of the other remaining influencing variables; and
(iii) The causal variable is the independent variable and the outcome or effect is the dependent variable.
Cohen et al. (2007:274) stated that different kinds of experimental design could be employed, for example:
(i) A controlled experiment in a laboratory type environment;
(ii) A field or quasi-experiment in a natural setting as opposed to that of a laboratory type environment where variables are isolated, controlled and manipulated; and
(iii) A natural experiment in which it is not possible to either control or isolate the variables being studied.
Notwithstanding the perceived benefits of employing the experimental research approach, it is faced with numerous practical and ethical challenges. These could typically comprise the following aspects:
(i) In some cases, the independent variable cannot be manipulated for practical reasons and the possibility of employing experimental methods is thus negated;
(ii) In the case of the research focus being humans or animals, experimental manipulation of the independent variables could be regarded as being unethical; and
(iii) Given the practicality of employing and utilising the requisite resources, viz., human and physical, for the specific experimental study, may prove to be prohibitive.
Rose, Spinks and Canhoto (2015) provided the basic steps to be followed in an experimental study as summarised in Figure 3.6.
Figure 3.6 : Steps in an experimental study
Source: Rose, Spinks and Canhoto (2015)
Research Question Hypothesis Formulation Design Experiment Conduct Experiment Finding and Conclusions Existing Theory
An experimental design typically employs a deductive approach that is based upon the researchers enquiring questions and informed by existing theory. Rose et al. (2015) warned that it is important to clearly articulate and distinguish between the dependent and independent variables and their expected relationship. In addition to this it is also important to take cognisance of any extraneous variables that might need to be controlled during the experiment.
3.5.2 Case study research design
According Christensen, Johnson and Turner (2015:377), the case study approach is predominantly used in qualitative research and is defined as being an intensive and detailed description and analysis of one or more cases. Case study research is predominantly confined to the domain of psychology related research. According to Bryman and Bell (2011:59) the case study approach is also very popular and widely used research design in business research. If the case study approach is used in quantitative based research setting, a deductive approach to the relationship between theory and research will have to be considered. In essence, it is argued that the primary goal of the case study approach is to concentrate on the uniqueness of the case in question and to develop a deep understanding of the underlying complexity of the task at hand. Cohen et al. (2007:256) stated that one of the fundamental weaknesses of the case study approach lies in the fact that the research results may not be generalisable, except in an instance where other researchers see their respective application. Another weakness highlighted is the fact that research results are not easily open to cross-checking on the one hand and may thus be regarded as being selective, biased, personal and subjective in nature.
3.5.3 Cross-Sectional research design
Bryman and Bell (2011:53) defined cross-sectional research design as the collection of data on more than one case and at a single point in time in order to collect a body of quantitative or quantifiable data in connection with two or more variables. The cross-sectional design is often referred to as a social survey design, given the fact that questionnaires and structured interviewing are key components of this approach. In addition to this, it is important to note that cross-sectional studies are observational studies, viz., the researchers record their information about their respective subjects without manipulating the study environment. The principle
defining feature of a cross-sectional study lies in the fact that it can compare different population groups at a specific point in time. On the other hand, one of the major disadvantages of this approach is that cross-sectional studies may not provide information about cause-and-effect relationships. Christensen, Johnson and Turner (2015:78) stated that cross-sectional studies are sometimes employed in experimental research but are more often than not used in non-experimental quantitative research. Questionnaires and structured interviews are often the most predominant means of obtaining the relevant data for the research undertaking.
3.5.4 Longitudinal research design
Bryman and Bell (2011:57) stated that the longitudinal design approach represents a distinct form of research design that is typically used to map changes in business and management research. Abbot and Bordens (2011:352) stated that in a longitudinal design, multiple observations of the same participants are made across time. Unfortunately, this very procedure highlights problems that could possibly threaten the internal validity of the research project. Kumar (2011:109) shared this view and highlighted some predominant disadvantages of this approach in that longitudinal studies can suffer from the conditioning effect, which is defined as a situation whereby the same respondents are contacted frequently and the aforementioned become accustomed to the questioning regime and over time could result in the quality or feedback of the responses being compromised. On the other hand, a main advantage of this approach is that it allows the researcher to measure the pattern of change and obtain factual information, requiring collection on a regular basis and thereby ensuring that the accuracy of the responses is enhanced.
3.5.5 Comparative research design
Kumar (2011:118) stated that within a comparative based research design framework, a study can be carried out either as an experiment or as a non- experiment. The fundamental tenet of the comparative research design involves the study population to be divided up into the same number of groups as the number of treatments to be tested. For each group, the baseline with respect to the dependent variable is established. Once this has been carried out, the different treatment models are introduced amongst the different groups. Once this task has been completed, changes with respect to the dependent variable are noted. The
effectiveness of the interventions is determined by the extent to which the degree of change of the dependent variable is observed amongst the different population groups being analysed. The next section identifies and discusses all the relevant aspects pertaining to the study population considered in this study.