Chapter 3: Methodology
3.3. Instruments
It is important to note that this method is not based on the premise that theory and methods will emerge during the course of the research as in qualitative research, because quantitative research is more specific and predetermined (Gravetter & Forzano, 2009). On the one hand, it is an advantage to use a specific and predetermined method because it gives a study a sense of direction and helps keep focus. On the other hand, it limits the inclusion of other relevant and necessary considerations once started (Stevenson, 2001).
The second set of the questionnaire was derived from the work of Flisher and his colleagues (1993), in order to assess adolescent risk-taking behaviour. The original risk-taking behaviour scale consisted of demographic questions, and three other parts. Part 1 focused on unintentional and intentional violent behaviour, and suicidal behaviour; Part 2 focused on substance use and abuse (like alcohol consumption, cannabis, solvent and injectable drugs); Part 3 dealt with aspects of sexual behaviour and prevention against disease or pregnancy.
The adapted risk-taking behaviour scale for the current study consisted of two parts, which were mainly taken from part 2 and 3 of the original risk-taking behaviour questionnaire by Flisher et al. (1993a). Therefore, all items pertaining to risk-taking behaviour that focused on sexual-risk, alcohol, cigarette and drugs were included.
Items pertaining to demographic information such as age, gender, race, and level of study were also included in this study’s questionnaire. However, no personal identifying information such as student number, identification number (ID), home or postal addresses, cell phone numbers, and names were required. According to their risk-taking behaviour questionnaire, Flisher et al. (1993a) mentioned that the questionnaire was a self-administered instrument, which required a “yes” or “no” responses. Moreover, they intentionally focused on observable risk- taking behaviour rather than focusing on items that explored attitudes and beliefs on risk-taking behaviour because such items are usually infused with cultural influences and biases, of which they wanted to eliminate or minimize by excluding those type of questions or items. As a result, the current study also focused on observable risk-taking behaviour and excluded questions on attitudes and beliefs. Questions included in the current study’s risk-taking behaviour questionnaire are outlined Section A of the final questionnaire in Appendix A.
The validity was assessed by using a factious drug called “derbisol”. Participants were asked if they have ever used this factitious drug. All participants who responded “yes” to using this factitious drug were discarded from the study (Flisher et al., 1993a). However, no participant in this current study reported ever using this hypothetical drug. Furthermore, this instrument has been subject to extensive and several pilot studies, whereby clarity-seeking interviews were also done, mainly to boost the validity of the questionnaire and to make it more efficient (Flisher et al., 1993a; Wild et al., 2004).
Similar versions of this instrument or risk-taking questionnaire have been utilized in other school-based epidemiological studies in South Africa (Flisher, 1998). Therefore, it is beyond doubt that this questionnaire has a strong validity.
Stevenson (2001) contends that effective questionnaires are usually short and straight to the point. Hence, the study’s final scale was succinct, and it only required a short time to administer, which boosted the present study’s data collection process because respondents remained interested when completing the questionnaire, unlike long questionnaires that prove to be tedious and produce less interested participants who fabricate responses.
Although the current study’s questionnaire reliability and validity were well established, further reliability analysis for this questionnaire was run through the IBM SPSS Statistics 21 in order to specifically confirm their reliability for this study, since it was administered on a different sample. Prior to any reports on the reliability scores for this study, it is important to briefly describe what reliability analysis is all about.
Reliability analysis is all about the same scale yielding similar results when administered again under similar conditions, and it is necessary because most scales ( or observation methods) usually lack consistency, thus affecting the usefulness of the findings generated by that measure(Goodwin, 2002). The Cronbach’s coefficient alpha was used to determine the scales’
reliability instead of split-half and test-retest reliability measures. The Cronbach’s coefficient alpha was chosen because it is widely used by researchers than the other measures of reliability, which are usually laborious and difficult to administer (Aron & Aron, 1997). For a significant and useful scale, the Cronbach’s alpha should be at least 0.7 or greater (Finchilescu, 2010).
Both scales for this study were proven to be reliable trough reliability analysis. The reliability score for the Rosenberg Self-esteem scale was found to be reliable (Cronbach’s alpha
= 0.750), indicating that the scale is useful and produced trustworthy findings. Although the Risk-taking Behaviour scale had a Cronbach’s alpha value of 0.614, it was also declared reliable because the reliability value of 0.65 is adequate if the scale is to be used to compare groups of people (Finchilescu, 2010), it was nearly significant due to the slight difference from the significance cut-off point.
For determining validity, content validity, criterion-related validity, and construct validity are primary aspects of validity to be examined (Finchilescu, 2010), and only the first two mentioned were relevant and considered for the current study’s validity. Content validity pertains to the extent to which a test or measure accurately represents the domain of the construct being measured, and criterion-related validity refers to the extent of how a measure or test accurately predicts a criterion behaviour or outcome either in the present or future (Finchilescu, 2010; Goodwin, 2002).
The current study’s questionnaire had a strong content validity because of its relatively strong face validity, and has gained approval from expert judges. Face validity (refers to the appearance and authenticity of the test or measure) and expert judges (that is, supervisor and ethics committee reviewers) are determinants of content validity (Finchilescu, 2010). For instance, it is without doubt that the current study’s questionnaire measures what it is supposed to measure because the items in the questionnaire show authenticity and measure the domain’s constructs under investigation (that is, self-esteem and risk-taking behaviour), and has gained approval from the ethics committee and supervisor.