In qualitative research, the forms of quality assurance of reliability and validity concern trustworthiness. In what follows, I provide a discussion of the constructs reliability and validity in a qualitative research paradigm and give an explanation on how they are accounted for in this study.
4.6.1 Reliability
The construct reliability refers to the consistency of a research instrument used to collect data (Choongwa, 2018). In the context of research, an instrument is reliable if the same instrument produces similar findings when administered to different subjects from the same population, Maree (2007). In short, both authors agree that reliability is about an extent of an instrument being repeatable and consistent. Hence in qualitative research this would be a question of why the study should be trusted. This would incorporate the procedure of research strategies and meaning making of the data generated.
Thus, it can be argued that in qualitative research, reliability can be checked and enhanced by the use of different methods of data collection. This would permit the analysis and explanation of the data collected from different perspectives, thus reducing the possibility of bias by the researcher and sample thereby establishing worthiness of the data. In order to facilitate the validation of the data, the study was subjected to triangulation.
79
Cohen et al. (2000) defines triangulation as the use of two or more methods of data collection in research. Triangulation improves the objectivity of the study by the use of multiple data collection methods in one study of a single phenomenon to build on a single construct in qualitative research (Yeasmin and Rahman (2012). Thus, in the current study, two data collection instruments were used to generate data. The major instruments that were subject to triangulation were lesson observation and teacher interviews. In both instruments, audio recordings were created on soft copies. Also, the researcher took observational field notes as the lessons progressed. Lesson plans for the observed lessons of each of the three teachers were taken after they had taught their lessons.
Apart from the lesson observations and teacher interviews, the field notes and the teachers’ lesson plans for the observed lessons were also used in the data analysis. Thus data were triangulated in this study over the use of observations captured on video camera, interviews, observational field notes, and Mathematics lesson plans.
4.6.2 Validity
In quantitative research, Maree (2007) defines validity as the extent to which it measures what it is supposed to measure. Additionally, Creswell (2015) defines validity in quantitative research as a research activity in which the researcher embarks on certain procedures to check for the accuracy of results.
However, in qualitative research, validity is viewed as the degree to which the researcher reflects reality as it is lived on by the participants in social contexts (Maxwell, 1992). Furthermore, Maxwell argues that validity is always relative to the purposes and circumstances of the research and dependent on some community of enquiry on whose perspective the account is based. Therefore, the appropriateness and usefulness of the inferences a researcher draws (Fraenkel & Wallen, 1990) in reference to particular settings reflects the validity of research methods.
There are quite a number of validity conditions that a researcher can use to ensure the meaningfulness of his/her study. However, Maxwell (1992),
80
mentions five categories of validity and these are descriptive validity, interpretive validity, theoretical validity, generalizability validity and evaluative validity. Of relevance to this study are descriptive validity, theoretical validity, and generalizability validity.
With regards to descriptive validity, Maxwell (1992) argues that most qualitative researchers are concerned with factual accuracy of their account of the things they saw and heard. In this study, descriptive validity was achieved in the sense that, during the interviews, teachers’ words and utterances were recorded accurately using an audio recording device. The audio recordings were then transcribed (see Appendices). The researcher went through each transcript whilst listening to the audio recording to ensure that the transcription reflected the teachers’ words and utterances. Extracts from the transcriptions were used to substantiate claims and these contributed to the trustworthiness of the study.
Also, the interviews with the teachers were conducted privately in a closed environment. As such the interview transcripts accurately reflected what the teachers said hence the study could be considered to have descriptive validity.
According to Maxwell (1992), theoretical validity concerns the concepts used to explain the data and the relationships between them. Furthermore, he contends that theoretical validity depends on whether there is consensus within the research community about the validity of the terms and concepts. In the present study for example, theoretical validity was achieved by deriving and providing clear descriptions of the constructs learner-centred teaching, and meaningful learning using the literature as a basis.
Lastly, Maxwell (1992) argues that generalizability validity in qualitative research refers to the extent to which one can extend the account of a particular situation or populations to other persons, times, or settings than those directly studied. In this study, being a case study, it is not possible to make generalizations about the findings applicable throughout Eswatini or in other countries. However, the transferability of the findings depend on the level of details about the methods, data collection, and analysis, and other researchers can study the details and decide whether the findings are applicable to their research setting.
81