As mentioned earlier, the researcher and his assistant piloted the structured observation schedule in two different multilingual mathematics classroom settings in order to satisfy the requirements suggested by Gibson and Brown (2009). The observation schedule used in this study is a modified version of the classroom observation schedule used and validated in a number of other studies (Mayaba, 2009).
7.5 Overview of reliability and validity in this study
In order to assess the acuracy of the findings and convince readers of such accuracy, the researcher incorporated the use of multiple validity strategies as recommended by Creswell (2009):
Triangulated various data sources of information by testing evidence from the sources and using it to build a strong justification for themes. This process added value to the validity of this study because themes were established based on converging several sources of data and perspective from participants;
The researcher used member checking to determine the accuracy of the
qualitative findings through specific rich descriptions and themes (only polished products and not all transcriptions) by referring findings back to the participants to find out if they agreed with the accuracy of findings. This procedure was done through follow-up (focus) interviews with participants in the study and giving them an opportunity to comment on the findings;
The researcher used a peer debriefing to enhance the accuracy of the account
through an external peer debriefer in the field of this study, who reviewed and asked questions about the qualitative part of this study;
A prolonged time was spent at the research site and repeated observations
were made to further develop an in-depth understanding of the phenomenon under study. This procedure enabled the researcher and his research assistant to obtain more experience with the participants in their natural setting, which gave the researcher more accurate or valid qualitative findings; and
The researcher clarified the bias that is brought to the qualitative phase of the
study. The researcher has commented about how the interpretation of findings is shaped and/or influenced by his background, such as culture, history, socio- economic origin, etc.
The primary strategy utilised in this study to ensure external validity was the provision of thick, rich and detailed descriptions so that anyone interested in transferability will have a solid framework for comparison (Merriam, 1988). Nixon and Power (2007) point out that warranting of claims must fulfill the criteria of trustworthiness, soundness, coherence, plausibility and fruitfulness. Trustworthiness refers to the quality of qualitative data collected (Anastas, 2004); and in the sense of neutrality in the findings or decisions of the study (Guba & Lincoln, 2005).
Reliability is the degree to which the instrument measures whatever it is measuring consistently (Best & Kahn, 2003; Ary, Jacobs & Razavier, 1990). According to Silverman (1999), reliability refers to the degree of consistency with which instances are assigned to the same category by different observers or by the same observer on different occasions. Neuman (2003) suggests reliability has to do with the issue of dependability. Dependability of data in this study, was established by capturing all the interviews and observations on a tape and video recorder, and was transcribed both manually in writing and using computer software. Attempts were made to reproduce the interview scripts as accurately as possible to eliminate possible threats to reliability of the instruments used in this study. Creswell (2005) defines threats as the problems that threaten our ability to draw correct cause and effect inferences that arise because of the experimental procedures or the experiences of participants.
The researcher followed the following procedures, as suggested by Gibbs (2007), in order to ensure reliability in this study:
The researcher checked all the transcripts for possible mistakes made during
the initial transcription;
During the process of coding, the researcher ensured that definition and
meaning of codes were consistent throughout the entire qualitative data analysis, by regularly comparing data with the codes and by writing memos about the codes and their definitions; and
The researcher cross-checked codes developed within the existing literature by
comparing results that are independently derived.
The researcher made an attempt to include these procedures as evidence that he strove to obtain consistent results in this study. The assistant researchers had the role of
independently cross-checking the codes through the process of intercoder agreement (Creswell, 2009) between the researcher and his assistant.
8. ETHICAL ISSUES
According to Babbie (2007) and Babbie and Mouton (2008), researchers have a duty and obligation to abide by the code of conduct that governs most professions. Neuman (2003) argues that researchers have a moral and professional obligation to be ethical, even when research subjects are unaware of or unconcerned about ethics. When conducting research, social scientists enter into the private lives of their participants (Berg, 2001). Researchers therefore have to make sure that the privacy, the rights, and the welfare of their participants are guaranteed (Kumar, 1999).
In this study, informed consent from participants was requested after prior permission to conduct this research, as part of the Integrated School Development and Improvement (ISDI) project offered by the CERTI at NMMU, was granted by the Education, Research Technology and Innovation Committee (ERTIC) of the NMMU. After obtaining ethics clearance, the researcher approached the principals and teachers of the participating schools, where their roles as participants, right to choose to be participants and to participate or not in this study were explained to them. They were assured of confidentiality that participation was voluntary and were given a guarantee that they could withdraw from the study at any time and that no personal details would be disclosed. Confidentiality of information collected in the schools was also ensured and that no portion of the data collection would be used for any purpose other than this research.