METHODS TO ENSURE VALIDITY (CREDIBILITY)

According to Ellis et al. (2010:124), validity refers to the degree to which one is measuring what is intended to be measured. Validity of qualitative data depends on the methodology applied by the researcher, and the accuracy of data determines the validity of the research (Patton, 2002:11). According to Kumar (2011:184), one of the areas of difference between quantitative research and qualitative research is in the use of, and the importance given to, the concepts of validity and reliability.

The procedures for assessing validity and reliability may, according to Singleton and Straits (2010:145), seem so complex and cumbersome to the extent that some researchers find it difficult to pass beyond this stage of research.

Schurink, Fouché and De Vos (in De Vos et al., 2011:419) remark that two qualitative researchers, namely Lincoln and Guba, suggest four indicators, namely credibility, transferability, dependability and confirmability, in a qualitative study to determine trustworthiness, and it is these four indicators that reflect validity and reliability in qualitative research.

Maxfield and Babbie (2012:212) and Vithal and Jansen (2010:32) state that validity is an attempt to check out whether the meaning and interpretation of an event is sound, or whether a particular measure is an accurate reflection of what you intend to find out. If a highly unreliable measure cannot be valid, how can you measure something accurately if the results fluctuate wildly? (Singleton & Straits, 2010:131).

Silverman (2000:188) asserts that the procedure and methodology that the researcher used must be clearly described in such a way that when another researcher repeats the research, he would produce the same outcomes. To strengthen the validity of findings, Silverman (2013:289-296) mentions the interrelated ways of critical thinking about qualitative data analysis, namely:

refutability principle, the constant comparative method, comprehensive data treatment, deviant case analysis and using appropriate tabulations. These interrelated ways are discussed below, followed by the indicators of trustworthiness.

2.8.1 Refutability principle

One solution to the problem of anecdotalism is simply for qualitative researchers to seek to refute their initial assumptions about their data in order to achieve objectivity (Silverman, 2013:289). According to Creswell (2014:201), to strengthen the accuracy of data in qualitative research, the researcher must conduct follow-up interviews with participants in the study and provide an opportunity for them to comment on the findings.

The researcher ensured that all participants were contacted. The aim of the follow-up interviews was to verify the validity of the information that the participants had submitted during the first round of interviews, even though some of them were reluctant to be re-interviewed. Nonetheless, the intention of the researcher was to ensure that he had sufficient and correct information to strengthen the validity.

Besides all these interventions, Silverman (2013:289) points out that the knowledge gathered is provisional, subject to the subsequent study, which may come up with baffling evidence.

2.8.2 Constant comparative method

Silverman (2000:180) postulates that the researcher should continuously inspect, compare and analyse all the data as obtained. The comparative method means that the qualitative researcher should always attempt to find another case with which to test out a provisional hypothesis (Silverman, 2013:290). In this study, the researcher ensured that all data were inspected for accuracy, compared and analysed. Firstly, the same standardised interview schedules were used specifically for the selected samples. In other words, the researcher developed and administered the same interview schedule for all participants of Sample A and the same method was applied for Sample B. For the purpose of international comparison, the researcher used the same interview schedules for Sample C and Sample D, considering the differences in legislation relating to criminal investigation and prosecution procedures that govern the countries of the participants. In this regard, the researcher ensured that in the interview schedules, the names of the police departments in Samples C and D were recorded correctly.

The researcher is of the view that in order to measure something accurately, consistency has to be applied. The answers provided by the participants were measured and compared to ensure that they answered the research questions as alluded to by Fink (1995:50), who states that to obtain validity, the researcher has to employ standards that have a meaningful link to the research questions.

2.8.3 Comprehensive data treatment

Silverman (2013:292) points out that in qualitative research, the researcher works with smaller data sets as compared to quantitative research; for that reason, the researcher should not be satisfied until one generalisation can be applied to every single piece of relevant data collected. According to Steyn (2002:71), the results of a research study can be generalised to groups that participated in the research. The generalisation occurs when qualitative researchers study additional cases and generalise findings to the new cases (Creswell, 2014:204).

Care was taken to ensure that the participants were credible and had knowledge of the phenomenon under study. The researcher deemed the selected samples to be correct and is of the view that any researcher will arrive at similar findings when conducting additional research, following a similar research process in a similar context.

2.8.4 Deviant-case analysis

To Silverman (2013:292), the qualitative researcher should not be satisfied with the explanations that appear to explain nearly all the variances in their data but they should use every piece of data until it can be accounted for. Peräkylä (in Silverman, 2011:369) states that after having established a pattern, the researcher’s next task is to search for and examine deviant cases: cases where ‘things go differently’- most typically, cases where an element of the suggested pattern is not associated with the other expected elements.

During the interviews with participants, the researcher was mindful of the non-verbal communication that the participants might have expressed when answering questions. Equally, the researcher was also cautious of triggering reactions that might influence the responses of the participants. The researcher analysed all data

cases. To strengthen the validity of the research, the researcher made use of content analysis. Throughout the study, the researcher remained as objective as possible.

2.8.5 Using appropriate tabulations

Silverman (2013:296) states that it is a mistake to count for the sake of accounting.

He further states that without a theoretical rationale behind the tabulated categories, counting only gives a spurious validity to research. He urges that qualitative researchers should not close their eyes to the importance of using quantification in the qualitative research. Simple counting techniques, theoretically derived and ideally based on members’ own categories, could offer a means to survey the whole corpus of data ordinarily lost in intensive qualitative research (Silverman, 2013:298).

In this regard, the researcher included counting techniques derived from the interviews as alluded to by Silverman (2013:296-298).

2.8.6 Credibility/authenticity

Credibility deals with the congruence of the findings with reality (Shenton, 2004:14).

Schurink, Fouché and De Vos (in De Vos et al., 2011:419) explain that credibility is the alternative to internal validity, and with credibility the goal is to demonstrate that the research was conducted in such a manner as to ensure that the participants had been accurately identified and described. In this research, participants were selected from the SAPS and NPA. In the CJS, the SAPS is mandated to conduct criminal investigation, while the NPA is responsible for the prosecution of the alleged offenders. The researcher believed that in order to answer the research questions, the participants from these two institutions were most suitable. The researcher increased the credibility of the findings by means of prolonged engagement and persistent observation in the field, triangulation of different methods, making use of formalised qualitative methods, and member checks.

2.8.7 Transferability

Schurink, Fouché and De Vos (in De Vos et al., 2011:420) explain that the researcher must question whether the findings that the research produced can be transferred from a specific situation to another. This is viewed as an alternative to external validity or generalisability. To ensure transferability, the researcher ensured

that personal information of the participants such as qualifications and experience was obtained and considered. Even though the researcher encountered problems with this data collection, such as that some of the participants were of the view that the personal information such as age and race was too sensitive, the majority of them nonetheless answered the questions. The researcher is of the view that the findings can be transferred from a specific situation to another.